GAS WARFARE Gas Warfare 
BY 
EDWARD S. FARROW 
»• * 
LATE ASSISTANT INSTRUCTOR OF TACTICS, AT THE 
UNITED STATES MILITARY ACADEMY, WEST POINT, NEW YORK 
Author of Farrow's "Military Encyclopedia," "American Small Arms," 
"Dictionary of Military Terms," "Manual of Military Training," 
"Riots and Riot Duty," "American Guns in the 
War with Germany," Etc. 
"What is obvious is not always known, 
what is known is not always present." 
-Johnson 
NEW YORK 
E. P. DUTTON & COMPANY 
681 FIFTH AVENUE Copyright, 1920, 
BY E. P. DUTTON & COMPANY 
All Rights Reserved 
Printed in the United States of America THIS WORK 
IS INSCRIBED BY ITS AUTHOR 
TO 
THOSE MEN WHO WITHOUT DEFENSE 
BORE THE BRUNT OF 
THE FIRST GAS ATTACK 
AT YPRES PREFACE 
Concentration, surprise in tactics, and the use of 
unexpected new materials are three most important 
things in Gas Warfare. With the first gas attack, 
the whole course of the war with Germany changed. 
This attack was made against men who were en- 
tirely unprepared and absolutely unprotected, and it 
was no exaggeration when the Germans claimed that 
6,000 of our men were killed and as many taken 
prisoners. Never had such a battlefield been seen in 
warfare, ancient or modern. 
The official records show that in the war with 
Germany the casualties from gas equaled 2*4 per 
cent, while those from bullets and high explosives 
equaled 25 per cent, thus demonstrating that gas 
is a most humane weapon of war. The early gas* 
clouds soon gave way to gas shells, the most effec- 
tive materials for the latter being mono- and tri- 
chloromethyl-chloroformate. Prussic acid was lit- 
tle used as it was rated lower than phosgene in 
toxicity. 
I believe that gas and military aeronautics will 
play the principal parts in the next war, which will 
be literally finished in the chemical laboratory. I 
have, therefore, prepared this volume to assist in 
educating our soldiery in the use of gas in both de- 
fense and offense. I am indebted to Generals Wil- 
VII VIII 
PREFACE 
liam L. Sibert and Amos A. Fries, who led in actual 
gas warfare against the Germans, and to other offi- 
cers with whom I have conferred. 
Edward S. Farrow. 
New York City, May, 1920. CONTENTS 
CHAPTER PAGE 
I. War Gas Investigations, Bureau of Mines Activi- 
ties, Gas Masks and Rescue Apparatus, Re- 
search Work, Lethal and Neutralizing Substances, 
Toxicity Tests and Divisions of Chemical War- 
fare Service I 
II. Toxic Gases, Early Employment in Warfare, De- 
velopment in the War of 1914-1918, the Edge- 
wood Arsenal, Chlorine Plants, Chlorpicrin 
Plants, Phosgene Plants, Mustard Gas Plants, 
Filling and Spray Painting Plants, Chemical 
Warfare Production Data 12 
III. Gas Defense Equipment, the Problem of Gas 
Masks, Box Respirator Equipment, Canister In- 
gredients, Carbon (Charcoal) for American 
Canisters, Horse Mask Development, Production 
Data of Gas Defense 27 
IV. Tactical Employment of Gases, Importance of Gas 
as a Weapon in Military Operations, Lachrymat- 
ors or Tear Producers, Density of Gases and Time 
of Exposure, Gases from Shells, Artillery Gas 
Zones of Dispersion, Effects of Temperature 
and Terrain 40 
V. Tactical Use of Artillery Chemical Shell, Smoke 
Screens and Smoke Shell, Handling and Storage 
of Gas Shell, Transport and Storage of Gas Shell, 
Gas Shell Dumps and Batteries 53 
VI. Chemical Artillery Ammunition, Construction of 
Gas Shell, Types of American Shell, Smoke Shell, 
Incendiary Shell and Fuses, Fillings for Gun and 
Howitzer Shell 68 
VII. Smoke for Military Purposes, Phosphorous and 
Tetrachlorides, British "S" and B. M. Mixtures, 
Smoke Screens, Smoke Shell, Protection of 
Tanks 93 
IX X 
CONTENTS 
CHAPTER PAGE 
VIII. Chemical Weapons for Use by Infantry, Incendi- 
ary Grenades, Thermit Hand Grenades, Tactical 
Use of Gas Grenades, Tactical Use of Smoke 
Grenades, Smoke Candles, Stokes Mortar Smoke 
Bombs 100 
IX. Persistencies of Gases, Methods of Projection, Em- 
ployment of Chemical Substances in Tactics, 
Phosgene, Chlorpicrin, Mustard Gas, Bromben- 
zyl-cyanide, Special Application of the various 
Groups 114 
X. Use of Gas by Gas Troops, Organization of Gas 
Regiment, Duties of Regimental Officers, Duties 
of Company Officers, Stokes Mortars and 
Bombs, Smoke Bombs, Propellants and Fuses, 
Livens Material, Cloud Gas Apparatus, Gen- 
eral Procedure in Gas Operations 125 
XI. Tactical Use of Gas, Thermit and Smoke by Gas 
Troops, Choice of Weapons, Training of Gas 
Troops, Liaison, Service of Security and Infor- 
mation, Training of Special Detachments . . 152 
XII. Use of Gas by the Air Service, Tactical Use of In- 
cendiary and Smoke Bombs, Altitude Flying and 
Oxygen Apparatus, Chanard Incendiary Bombs, 
Training Smoke Bombs 166 
XIII. Gas Zones, Gas Alarms, Gas Sentries, Action during 
and after Gas Attack, Division Organization of 
Disinfecting Service, Duties of Regimental and 
Battalion Gas Officers 174 
XIV. Respirators, Adjustment and Practice Drills, 
American Tissot. Respirator, Fitting and Care of 
Canisters, Anti-Dimming Outfit, Respirators 
for Horses 184 
Appendices 
1. Warfare Gases 199 
2. Carbon Monoxide 205 
3. Chlorine 209 
4. Phosgene and Lethal Gases 213 
5. Nitrous Fumes and Lachrymators 219 
6. Mustard Gas 222 
7. Gas Attacks 227 CONTENTS 
XI 
PAGE 
8. Defense Against Gas 232 
9. Functions of Gas Officers 238 
10. Casualties by Gas in the American Expeditionary 
Forces 244 
11. Auto Gas Measures Affecting Special Arms . . 245 
Index 249 GAS WARFARE GAS WARFARE 
CHAPTER I 
War Gas Investigations, Bureau of Mines Activities, Gas 
Masks and Rescue Apparatus, Research Work, Lethal 
and Neutralizing Substances, Toxicity Tests and Di- 
visions of Chemical Warfare Service. 
In February, 1917, when war between the United 
States and Germany seemed inevitable, the Bureau 
of Mines took up the question of what it could do 
to most advantage in the event of war. Since its 
establishment in 1910, it had maintained a staff of 
investigators studying poisonous and explosive gases 
in mines, the use of self-contained breathing appar- 
atus for exploring mines filled with noxious gases, 
the treatment of men overcome by gas, and similar 
problems. At a conference of the director of the 
bureau with his division chiefs, in February, 1917, 
the matter of national preparedness was discussed, 
and especially the manner in which the bureau could 
be of most immediate assistance with its personnel 
and equipment. One of the things decided was to 
investigate gas masks and rescue apparatus for mil- 
itary and naval purposes. 
Beginning with an investigation to develop the 
best type of gas mask, the scope of the work ex- 2 
GAS WARFARE 
tended until it included researches relating to a wide 
range of devices, such as different types of poison- 
ous and irritating gases and smokes, smoke screens, 
gas shells and gas bombs, flame throwers, trench 
projectors for firing gas bombs, signal lights, and 
incendiary bombs. The development of special 
oxygen breathing apparatus, similar to that used in 
mining, for naval or military use soon followed. 
The National Research Council was at once or- 
ganized to act as an intermediary on research be- 
tween the scientists and the Universities of the 
country and the various departments of the govern- 
ment and to suggest and consider research problems. 
By June 30, 1917, the personnel engaged in research 
work comprised 50 paid investigators, and the work 
had expanded from the devising of gas masks to the 
study of poison gases and chemical appliances for 
offensive warfare. One of the early results of the 
research work undertaken by the Bureau of Mines 
was the establishment of the chemical service as a 
unit of the National Army. Colonel William H. 
Walker commanded the American branch of the 
Chemical Service, reporting to the Gas Warfare 
Division and the Chemical Service Section in 
France. Subsequently Colonel Walker was trans- 
ferred to the Ordnance Department and put in 
charge of enormous plants for making chemicals 
for gas warfare that were erected at Edgewood 
Arsenal. The establishment of this unit was a 
noteworthy fact in the history of applied chemistry, 
for never before in any war or in any country had 
chemistry been recognized as a separate branch of 
the military service. 
By May, 1918, the question had arisen as to GAS WARFARE 
3 
whether the research work on war gases should be 
transferred to the War Department or should con- 
tinue under the Bureau of Mines. Army officials 
believed that the work could be coordinated better 
by having it under military control. On the other 
hand it was held that there was nothing to be gained 
by a transfer of authority as the research work had 
kept well in advance of the manufacturing develop- 
ment in progress under the War Department and the 
development of methods of manufacture had been 
conducted so expeditiously that the supply of toxic 
materials exceeded the supply of shells. The coun- 
sel of those Army officers who believed the research 
work should be transferred to the War Department 
prevailed, and on June 25, 1918, under the authority 
given by what is known as the Dverman Act, Presi- 
dent Wilson transferred the work being done at 
the Amercan University from the Bureau of Mines 
to the Chemical Service of the Army. 
For the purposes of study and research the war 
gases, many of which are liquids at ordinary tem- 
peratures and pressures, were divided into two gen- 
eral classes (a) lethal substances, generally those 
that kill by asphyxiation, and (b) neutralizing sub- 
stances. The neutralizing materials are less poison- 
ous but are capable of putting men out of action for 
shorter or longer periods of time. To this class 
belong lachrymators (or tear gases), sternutators 
(or sneezing gases), and eye, lung, and skin irri- 
tants, which inflame the eyes, cause severe respira- 
tory distress, and blister the skin. Absorbent sub- 
stances like charcoal, soda lime, sodium phenate, 
hexamethylamine tetramine, caustic soda, zinc ox- 
ide, etc., absorb or neutralize such gases as chlorine. 4 
GAS WARFARE 
phosgene, prussic acid, chlorpicrin, mustard gas, or 
xylyl bromide, and when used in gas masks protect 
against finely divided toxic solids such as diphen- 
ylchlorarsine; special clothing is needed for protec- 
tion against skin irritants such as mustard gas. 
In order to be deemed worthy of large-scale man- 
ufacture a new gas had to possess some quality or 
qualities that rendered it decidedly better for mili- 
tary use than its predecessors. It had to have high 
lethal value, be a powerful lachrymator or a good 
sternutator, or vesicant, or be more highly penetra- 
tive. The materials for its manufacture had to be 
plentiful and the process of manufacture could not 
be too difficult. When a new gas was under inves- 
tigation the procedure was about as follows: In 
the laboratories its physical, chemical, and physio- 
logical properties were determined, and methods of 
preparing it were investigated; then a plant for 
small-scale manufacture was designed. The gas 
was examined to determine how readily it pene- 
trated the American, English, French, and British 
masks. Also, tests were made to determine the best 
way of serving it to the enemy, whether in shells or 
from cylinders. In the meantime a thorough search 
was made for raw materials, for its manufacture. 
If all investigations proved satisfactory, it was 
turned over to the Ordnance Department-either to 
the development division, to build the first large unit, 
or to the gas manufacturing division. Chemists 
from the research division, who were familiar with 
the process of manufacture, were transferred along 
with the latter when it left the research division. 
As soon as the research staff had completed work 
on some of the more important substances, larger GAS WARFARE 
5 
plants were designed for manufacturing the mate- 
rials in quantities at the Edgewood Arsenal. 
Research to determine changes that take place 
in the body as the result of exposure to lethal gases, 
and thus to devise methods of treatment for gas 
poisoning, was organized at Yale University in 
May, 1917. After the pharmacological and toxi- 
cological research work was moved to the American 
University Station, therapeutic work was continued 
in the laboratories at Yale. For studying the organs 
and tissues of animals killed in gassing tests, a path- 
ological section was established in the summer of 
1917 with laboratories at the American University 
Station and at Yale University. Among the prob- 
lems attacked by the pathological division was the 
effect of mustard on the mucous membrane of the 
eyes and respiratory organs and on the skin. The 
pharmacological division was established at Ameri- 
can University in November, 1917, and in July, 
1918, it became the pharmacological research sec- 
tion of the Chemical Warfare Service. The work 
of this division comprised the following investiga- 
tions : 1. Devising toxicity tests by exposing mice, 
guinea pigs, rats, rabbits, cats, and dogs to poison 
gases, and by studying the pharmacological and toxi- 
cological effects. 2. Testing tear gases and sneez- 
ing gases on men. 3. Determining the skin-irri- 
tant effect of gases. 4. Testing fabrics for their 
permeability to mustard gas. 5. Devising analyti- 
cal methods for the control of the concentration of 
the gases used in tests. 6. Determining the sensi- 
tivity to gas of the skin of different individuals. 
Toxicity tests with animals covered a long list of 
poisonous liquids and vapors. Many of the tests 6 
GAS WARFARE 
with dogs were for varying lengths of time to de- 
termine the relation between the lethal effect and 
the concentration and length of exposure. Tests 
were also made with animals in a bomb pit at the 
American University station and at the Indianhead 
Proving Ground to determine the effective area of 
shells charged with the different toxic substances. 
A large number of fabrics were tested for per- 
meability to mustard gas, both dogs and men being 
used in the tests, and results of the tests were trans- 
mitted to the Army and Navy. Many tests with 
men and animals were made to determine the effect- 
iveness of tear gases and the minimum concentra- 
tion at which these gases could be detected by their 
odor or their irritating effects. One result of these 
tests was to show that man was more than one 
thousand times as susceptible to tear gas (xylyl 
bromide) as the horse, and more than ten times as 
sensitive as the dog. 
The pyrotechnic division was organized in June, 
1917. Among the tasks undertaken by its gas-shell 
section was the determining of the stability of vari- 
ous gases and toxic solids when used in shells. This 
section devised a training bomb for use by the gas- 
defense officers in cantonments, and studied lachry- 
matory bombs, smoke bombs, and noise bombs. 
Also, several gas-producing chemical combinations 
were submitted to the Bureau of Ordnance of the 
Navy for use in armor-piercing shell. The smoke- 
screen section prepared specifications for a Navy 
smoke funnel and a smoke-box float; it also per- 
fected a smoke signal for airplane bombs that was 
accepted by the Ordnance Department, also a sim- 
ilar device for use in the Navy dummy airplane GAS WARFARE 
7 
bomb. A portable smoke apparatus using silicon 
tetrachloride was designed for the Army, a smoke 
mixture of phosphorus and TNT, for use in shells 
and in candles, a smoke bomb of the Liven's type, 
a smoke grenade, and a "noiseless" nozzle for gas 
attacks. A method of using oleum (fuming sul- 
phuric acid) to produce a smoke screen was accepted 
by the Navy. A new form of Stokes mortar was 
designed that gave greater accuracy and longer 
range. A long series of tests with Liven's projec- 
tors and projectiles were made to reduce the weight 
of the unit and to increase the range. The hand- 
grenade section was organized at the American Uni- 
versity Station in October, 1917, to continue work 
on grenades, but as the grenades already adopted 
by the Army were standardized, the section took up 
the testing of explosives used in pyrotechny and in 
gas warfare, and later, testing of high explosives. 
The sensitivity in use of various picrates was studied 
in order to assure proper safety measures in storing 
and handling being taken at the plant making chlor- 
picrin, for the Ordnance Department. Fragmenta- 
tion tests were made of hand grenades charged with 
TNT, amatol, and victorite, the last a chlorate ex- 
plosive; the results were forwarded to the Army 
and the Navy. Preliminary studies were made of 
the properties and usefulness of parazol and other 
chlornitro products as explosives. Studies of 
chlorate and perchlorate explosives led to the finding 
of satisfactory chlorate and perchlorate powders for 
use in hand grenades. A new explosive called ani- 
lite, which employs liquid NO2 as an oxidizing 
agent, and used by the French, was studied. After 
July 1, 1918, the hand-grenade section was desig- 8 
GAS WARFARE 
nated the explosives section of the Chemical War- 
fare Service. The incendiary section, organized as 
a separate unit in October, 1917, perfected a scatter 
type of bomb for the Army, devised an incendiary 
dart to be used from airplanes, an incendiary pro- 
jectile for use with the Liven's gun, and prepared 
recommendations for the Signal Corps as to the best 
type of explosives to be used with an airplane de- 
stroyer. After July 1, 1918, the section was reor- 
ganized as the inorganic section of the Chemical 
Warfare Service. The flaming-liquid section de- 
signed and perfected two portable flaming-liquid 
guns. Tests to determine full mixtures for use in 
connection with the flaming-liquid guns were made 
and recommendations submitted to the Ordnance 
Department of the Army. The signal-light section 
conducted a thorough investigation of green flares, 
devised several colored smokes for use in connec- 
tion with land signals and air signals, studied 
methods of improving the white flare, designed an 
illumination float to be dropped from an airplane, 
and constructed a special device to be used by sub- 
marines in signaling to surface craft. The lab ora^ 
tory section carefully studied linings, packings, and 
cements for gas shell. A shell that uses a special 
type of lead lining was recommended to the Ord- 
nance Department of the Army. Other work in- 
cluded the development of a systematic method for 
analyzing pyrotechnic materials, and a thorough 
laboratory study of the usefulness of paper and pulp 
containers for powder. The recommendations sub- 
mitted were adopted by the Ordnance Department, 
which had the tubes made in large quantities by 
June, 1918. The miscellaneous section designed a GAS WARFARE 
9 
smoke shell for the Navy, tested a special shrapnel 
shell with special loading for the Chemical Service 
of the Army, and made tests of silicon tetrachloride, 
stannic tetrachloride, and titanium tetrachloride for 
smoke grenades, to determine which smoke is the 
most obnoxious. 
The dispersoid division was established in April, 
1918, to study the small-scale production of smokes 
or mists and the best way of protecting men against 
them. Among the apparatus developed was a Tyn- 
dall meter for determining the rate of dissipation 
of smokes under varying conditions. Tests were 
started to obtain^systematic data on the toxicity and 
rate of dissipation of smokes, and rate of penetra- 
tion through filters and mask canisters. One of the 
problems taken up was the development of smoke 
candles. Besides the work on smokes, the dispersoid 
division continued some of the work on primers 
that was started at Urbana, Ill., using the Tolman 
hangfire measurer. Routine tests of airplane am- 
munition were made with this machine for the 
Ordnance Department. 
One of the largest of the branch laboratories en- 
gaged in the study of war gases was that of the 
Catholic University at Washington. The work done 
there included the study of various problems in or- 
ganic chemistry under the direction of Dr. W. K. 
Lewis; investigations of smokes and mists (dis- 
persoids) under Dr. R. C. Tolman; and the study 
of various problems of physical chemistry under 
Dr. W. D. Bancroft, including catalytic investiga- 
tions, such as the catalytic action of charcoal, the 
production of fluorine and fluorine compounds, the 
conversion of phosgene into superpalite, and the oxi- 10 
GAS WARFARE 
dation of alcohol to acetic acid. At Clark Univer- 
sity Dr. C. A. Kraus worked on the dimming of 
eyepieces of gas masks; on metal Dewar flasks for 
providing liquid oxygen for aviators and subma- 
rines; on the stability of gases; on a heat inter- 
changer for use on submarines; and on boosters for 
gas shells. At Yale University Dr. T. B. Johnston 
had charge of a staff of organic chemists that 
worked chiefly on the halogen ethers, on hydrogen 
selenide, and on certain selenocyanides. At Bryn 
Mawr Dr. R. F. Brunel studied the preparation of 
diazomethane and chlor and brom ketones. At Ohio 
State University Dr. C. A. Boord worked on mus- 
tard gas, phenylchlorarsine, diphenylchlorarsine, 
and on the selenium and tellurium derivatives of 
mustard gas, which for a time threatened to dis- 
place mustard gas. At Harvard University Dr. G. 
P. Baxter did much work on the physical constants 
of the war gases, especially their vapor pressures, 
thus supplying data that were essential for the 
proper use of these materials. Dr. E. E. Reid, of 
Johns Hopkins University, who became a consulting 
chemist of the Bureau of Mines in May, 1917, 
helped in interesting the chemists of the country in 
the work on noxious gases, and in having them sub- 
mit organic preparations. He had charge of a group 
of investigators working on problems of organic 
chemistry at the university. Dr. Reid Hunt, at 
Harvard University, with a staff of pharmacolo- 
gists, investigated toxicological problems. Dr. G. 
A. Hulett, head of the department of physical chem- 
istry at Princeton University was sent abroad in 
April, 1917, as a member of a commission appointed 
by the National Research Council to gather data on GAS WARFARE 
11 
technical war problems. He gave especial attention 
to the use of noxious gases in warfare, and brought 
back information that proved of immense value. 
In research as in the manufacture of gases and 
masks, the United States was without a peer. Gas 
intelligence, developed along with other lines of 
work, reached every part of the American Army 
and won not alone the respect and confidence of the 
general staff but of the Allied Armies as well. The 
Gas Regiment, which was handled directly by the 
Chemical Warfare Service in conformity with Gen- 
eral Battle orders, did work second to that of no 
other American regiment. It gassed the enemy 
heavily with Livens projectors and 4-inch stokes 
mortars, and did marvelous work with phosphorus 
and thermite in cleaning up machine gun nests in 
all the large battles of the Americans. No less im- 
portant was their work with smoke materials for 
screening troops in launching large attacks. The 
Chemical Warfare Service in the field made great 
strides and went far beyond expectation in develop- 
ing methods of attack, methods of protecting troops 
and in teaching the Army not alone how to defend 
itself against the enemy gas, but how to send that 
gas back at him more efficiently than he sent it over. CHAPTER II 
Toxic Gases, Early Employment in Warfare, Develop- 
ment in the War of 1914-1918, the Edgewood Ar- 
senal, Chlorine Plants, Chlorpicrin Plants, Phosgene 
Plants, Mustard Gas Plants, Filling and Spray Paint- 
ing Plants, Chemical Warfare Production Data. 
Suffocating gases were first used in warfare in 
the year 431 B. C., when sulphur fumes were em- 
ployed in besieging the cities of Platea and Belium 
in the war between the Athenians and the Spartans. 
Numerous similar uses of toxic substances are re- 
corded throughout the Middle Ages. In 1855, the 
English Admiral Lord Dundonald, having observed 
the deadly character of the fumes of sulphur in 
Sicily, proposed to reduce Sebastopol by sulphur 
fumes, and the details of the proposition were care- 
fully worked out. The English Government disap- 
proved the proposition on the ground that "the ef- 
fects were so horrible that no honorable combatant 
could use the means required to produce them." 
The probable use of poison gases continued in the 
minds of military men and at The Hague Confer- 
ence in 1899 several of the more prominent nations 
of Europe and Asia pledged themselves not to use 
projectiles giving out suffocating or poisonous gases. 
Germany signed and ratified this declaration in 
September, 1900, but the United States declined to 
sign it. Admiral Mahan, a United States delegate, 
12 GAS WARFARE 
13 
stated in substance in regard to the use of gas in 
shell, at that time an untried theory, that the re- 
proach of cruelty and perfidy addressed against 
these supposed shells was equally uttered previously 
against firearms and torpedoes, although both were 
afterwards employed without scruple. He held that 
it was illogical and not demonstrably humane to be 
tender about asphyxiating men with gas, when all 
were prepared to admit that it was allowable to blow 
the bottom out of an ironclad at midnight, throwing 
hundreds of men into the sea to be choked by the 
water, with scarcely the remotest chance to escape. 
The Second Hague Peace Congress in 1907 adopted 
rules for land warfare, the 23d article of which 
read as follows: "It is expressly forbidden to em- 
ploy poisons or poisonous weapons." 
The use of toxic gas in the European War dates 
back to April 22, 1915, on which day the Germans 
employed chlorine, a common and well known gas, 
in an attack against the French and British lines 
in the northeastern part of the Upper Ypres Salient. 
The methods of manufacturing toxic gases, the use 
of such gases, and the tactics connected with their 
employment, were new developments of this war. 
During the year 1918 from 20 to 30 per cent of all 
American battle casualties were due to gas, showing 
that toxic gas is one of the most powerful imple- 
ments of war. The records show, however, that 
when armies were supplied with masks and other de- 
fensive appliances, only about 3 or 4 per cent of the 
gas casualties were fatal. This indicates that gas can 
be made not only one of the most effective imple- 
ments of war, but one of the most humane. It will, 
of course, be necessary to remove the noncombatant 14 
GAS WARFARE 
population from a greater depth of country imme- 
diately in the rear of the fighting lines than formerly, 
in order that women and children may not be gassed. 
This additional sacrifice of territory for war uses is 
another element of effectiveness in the weapon. 
The use of toxic gas in warfare by Germany com- 
pelled the allied nations to adopt like tactics; accord- 
ingly England and France, faced with the desperate 
situation resulting from advantages secured by the 
Germans through the employment of these new 
weapons, immediately turned their attention not only 
to devising methods for protecting their own troops, 
but also to securing supplies and equipment neces- 
sary for the utilization of toxic gas as an agent of 
warfare against the German Army. Germany orig- 
inated thereafter the use of most of the new forms 
of gas, but the allied nations and America were actu- 
ally producing, at the time of the armistice, gases 
on a much greater scale than Germany was ever 
able to attain. In fact, America itself was produc- 
ing gases at a rate several times as great as was 
possible in Germany. 
In the early days of the belligerency of the United 
States the need of a plant for filling artillery shell 
with toxic gases was felt, and in the fall of 1917 
the Government purchased a large tract of land near 
Aberdeen, Md., to be an artillery proving ground. 
Approximately 3,400 acres of this reservation, about 
one-tenth of it in area, was set aside as the site for 
the gas shell-filling plant. This reservation was 
known as Edgewood, and the plant erected on the 
site was called the Edgewood Arsenal. Work started 
on the Arsenal construction November 1, 1917. 
By December 1, 1917, it was decided to build at GAS WARFARE 
15 
Edgewood a chlorpicrin plant and a phosgene plant. 
In March, 1918, the Edgewood project was taken 
from the Trench Warfare Section of the Ordnance 
Department and made an independent division under 
the command of Colonel William H. Walker. In 
June, 1918, the Chemical Warfare Service was or- 
ganized, and the Edgewood Arsenal was transferred 
to it. General William L. Sibert, Director of the 
Gas Service, took charge of the activities of the 
arsenal in May prior to the official transfer. 
Chlorine, the raw material for the manufacture 
of which is common salt, was one of the principal 
materials required in the gas-production program. 
Although chlorine was a standard product in the 
United States prior to the war, it was soon seen that 
there was an inadequate commercial supply to meet 
the requirements of the proposed gas offensive. 
Chlorine was used not only by itself, but it was also 
the active agent in the manufacture of nearly all 
the other toxic gases which were required. Conse- 
quently it was decided to build a Government 
chlorine plant with two 50-ton units, giving a daily 
capacity of 100 tons of liquid chlorine. The ground 
for this plant at Edgewood was broken on May 11, 
1918, and the actual production of chlorine begun 
on September 1. 
In July, 1917, the Germans introduced the so- 
called mustard gas. It was immediately realized 
that for certain purposes of fighting this chemical 
was the most effective product so far employed, and 
a large number of Government experts here at once 
concentrated their energies in developing methods 
for its manufacture on a large scale. It was decided 
to erect a large plant at Edgewood for the manufac- 16 
GAS WARFARE 
ture of mustard gas, the plant producing the first 
gas in June, 1918. It soon became evident that re- 
liance could not be placed upon civilian labor in the 
operation of this plant and other chemical plants 
at Edgewood because of the danger involved, and 
it was decided to utilize enlisted men in the working 
crews. As the projects at Edgewood increased in 
size and number, the forces at the arsenal grew, 
until at one time there were 7,400 troops at this 
point. In the spring of 1918, various scattered fac- 
tories by official order were made part of the Edge- 
wood Arsenal, each plant being designated by the 
name of the city or town where it was located. 
Thereafter in Army usage the term "Edgewood Ar- 
senal" embraced not only the group of factories 
on the Edgewood reservation, but also included 
projects at Niagara Falls, N. Y., Midland, Mich., 
Charleston, West Va., Bound Brook, N. J., and 
Buffalo, N. Y. In addition to these, the Edgewood 
Arsenal built at points advantageous to supplies of 
raw materials four other plants at Stamford, Conn., 
Hastings-on-Hudson, N. Y., Kingsport, Tenn., and 
Croyland, Pa., and operated them as well. 
In constructing and equipping the Edgewood Ar- 
senal the Government laid 15 miles of narrow- 
gauge railway and 21 miles of standard gauge rail- 
way, built 15 miles of improved roadway, and set 
up two water systems, one with a capacity of 
1,500,000 gallons per day for the manufacturing 
purposes of the chemical plants, and the other pro- 
viding a fresh-water supply pumped 4 miles with a 
daily capacity of 2,000,000 gallons; of a total of 
558 buildings, 86 were cantonment buildings, with 
a capacity of 8,400 men, and adequate quarters for GAS WARFARE 
17 
officers and civilian employees. Three field hospi- 
tals, a complete base hospital, and separate buildings 
for Y. M. C. A. and other activities indicated the 
extent of the building equipment. Three power 
houses were provided, with a total capacity of 
26,500 kilowatts. In the construction of buildings 
every precaution was taken to avoid accidents from 
the handling of toxic gases, the ventilating systems 
being as near perfection as scientific knowledge 
could make them. The following table of casualties 
in 1918 at the Edgewood Arsenal proper shows that 
all of the danger of the war was not confined to 
the front: 
Toxic agent 
Jun. 
Jul. 
'Aug. 
Sept. 
Oct. 
Nov. 
Dec. 
Total 
Mustard gas 
14 
41 
190 
153 
227 
47 
2 
674 
Stannic chloride.. 
3 
8 
15 
21 
3 
50 
Phosgene 
3 
7 
22 
17 
; 1 
50 
Chlorpicrin 
14 
18 
9 
3 
44 
Bleach chlorine... 
2 
39 
2 
I 
44 
Liquid chlorine... 
I 
3 
2 
7 
5 
18 
Sulphur chloride.. 
2 
I 
6 
9 
Phosphorus 
2 
7 
5 
I 
15 
Caustic soda 
3 
3 
4 
IO 
Sulphuric acid... . 
4 
3 
I 
8 
Picric acid 
2 
2 
Carbon monoxide. 
I 
I 
" Totals 
14 
279 
197 
293 
3 
92 
Chlorine was the only war gas produced on a 
commercial scale in America prior to the war. At 
the ordinary temperatures chlorine is a greenish- 
yellow gas of strong, suffocating odor. Through 
the combined effects of cold and pressure it is readily 
condensed to a liquid and is ordinarily shipped in 
this form, stored in strong cylinders. It is prepared 
commercially by the electrolytic process. A current 18 
GAS WARFARE 
of electricity is passed through a solution of com- 
mon salt. The greenish gas at once arises, leaving 
behind it a residue of caustic soda. The apparatus 
in which the salt is decomposed by the electric cur- 
rent is known as a cell. The Government plant used 
Nelson cells, each with a capacity of 60 pounds of 
chlorine and 65 pounds of caustic soda per 24 hours. 
The plant at Edgewood was ready for operation 
in August, 1918. It consisted of (1) a cell house, 
which had a total capacity of 100 tons of chlorine 
per 24 hours ; (2) an electric substation for supply- 
ing the current; (3) a brine building, where the salt 
was mixed with water and the resulting brine puri- 
fied; (4) a boiler and evaporation building, for con- 
centrating the caustic soda from the cells; (5) a 
caustic fusion building, for drying the caustic soda 
and fusing it into solid form for shipment; and (6) 
a liquefying plant to condense and liquefy 50 tons 
of chlorine per day. 
With the exception of chlorine, chlorpicrin was 
the first war gas to be manufactured on a large scale 
in the United States. When pure, chlorpicrin is a 
colorless liquid which boils at a temperature approxi- 
mately of 1120 C. The compound has been known 
since 1848. While not so poisonous as some of the 
other products used in gas warfare, it is, neverthe- 
less, an active poison, and has the additional advan- 
tage of being a fair lachrymator, or tear producer. 
It is made by the reaction between picric acid and 
chlorine. The chlorine is best supplied in the form 
of so-called bleaching powder, which is ordinary 
chloride of lime. In the manufacturing process as 
originally carried out, free picric acid was mixed 
with bleaching powder held in suspension with GAS WARFARE 
19 
water. Later it was found advantageous to use cal- 
cium picrate instead of picric acid. Accordingly, 
the final process was as follows: The bleaching 
powder was creamed with water and mixed with a 
solution of calcium picrate in large stills holding 
5,000 gallons or more. A jet of live steam was then 
introduced at the bottom of the still, and the reaction 
began at once, the rapidity depending upon the 
amount of steam introduced. The resulting chlor- 
picrin, together with a certain quantity of steam, 
passed out of the still and was liquefied in the con- 
denser. The resulting mixture of chlorpicrin and 
water was run into tanks, where the chlorpicrin, 
being insoluble in water, gradually settled to the 
bottom and was run off and used directly in gas 
shell. 
America's supply of chlorpicrin during the war 
came from the Edge wood Arsenal and the American 
Synthetic Color Company under a contract dated 
December 13, 1917; and the company shipped nearly 
112,000 pounds of the gas to Edgewood on March 
11. This, when mixed with the necessary stannic 
chloride, supplies of which were already on the 
ground, was sufficient to fill approximately 100,000 
75-millimeter shell. The chlorpicrin plant at Edge- 
wood went into entire operation in June, 1918. 
Phosgene was one of the deadliest gases employed 
in the European war. Numerous other gases were 
used to annoy the enemy and force the wearing of 
masks, but phosgene was a killer employed to pro- 
duce as many casualties as possible. The gas did 
not persist long in the air or on the ground after the 
shell had exploded, so that it was an ideal chemical 
for use in an attack. The gas would clear away by 20 
GAS WARFARE 
the time the troops following reached the place ot 
gas concentration. At ordinary temperatures phos- 
gene is a colorless gas, but it condenses to a liquid 
at 8° C. It is formed by the combination of two 
gases, chlorine and carbon monoxide, in the pres- 
ence of a catalyzer. The reaction is best conducted 
in iron, boxes- lined with lead and filled with char- 
coal^ of proper quality, into which boxes a stream of 
the. reacting gases, mixed in proper proportions, is 
introduced. The reaction creates heat, and means 
must usually be taken to keep the reaction boxes 
cooled. The* resulting phosgene is condensed to a 
liquid by passing the gas through a condenser which 
is surrounded by brine kept cold by refrigeration. 
The liquid is then stored in strong steel containers 
or run directly into Livens drums or artillery shell. 
Because of the great importance of phosgene in 
warfare the Government financed phosgene plants 
at Niagara Falls, N. Y., Bound Brook, N. J., and 
other places, and decided to build a Government 
phosgene plant at Edgewood, the construction of 
which was begun in March, 1918. It consisted of 
four catalyzer buildings, each building having four 
units, each unit possessing a projected capacity of 
5 tons of phosgene per day. The carbon monoxide 
used in the process was produced by passing a mix- 
ture of oxygen and carbon dioxide over heated coke 
in a gas producer, the oxygen being supplied by a 
Claude machine with a capacity of 100,000 cubic 
feet of oxygen every 24 hours. The chlorine used 
came partly from the Edge wood chlorine plant and 
partly from outside sources. The total output of 
phosgene at Edgewood was 935 tons, and that pro- GAS WARFARE 
21 
duced by all plants before the armistice was 1616 
tons. 
The Germans, in spite of their attainments in 
chemistry, were never able to improve their clumsy 
and expensive methods of producing mustard gas. 
The best reports we have show that at the time the 
fighting ended, all of Germany's chemical warfare 
facilities could not produce more than 6 tons of mus- 
tard per day. The United States alone had ten times 
that capacity on the same date, while France and 
England both reached a very heavy output. Known 
in chemistry as dichlorethyl sulphide, mustard gas 
is a colorless, slightly oily liquid, boiling at 220° C. 
with some decomposition. When perfectly pure it 
freezes at 140 C., but, since it usually contains small 
percentages of impurities, it usually remains liquid 
at o° C., or even below that. The first commercial 
process proposed for its manufacture depended upon 
the use of ethylene chlorhydrin. In the spring and 
summer of 1918 a new process was developed both 
in Europe and in the United States, one which used 
sulphur monochloride. This process consisted in 
blowing gaseous ethylene into liquid sulphur mono- 
chloride in large iron reaction vessels. Sulphur is 
set free by this reaction, and the temperature must 
be controlled in order to prevent the formation of 
solid sulphur in the reaction machine. The con- 
struction of the Edge wood plant was begun in May, 
1918, and the first mustard was produced a month 
later. At the time of the armistice the arsenal was 
producing 30 tons per day. The total production of 
mustard gas at Edgewood during the war period was 
711 tons, of which 300 tons went into shell. To in- 22 
GAS WARFARE 
sure an adequate supply of sulphur monochloride 
for its mustard gas production the Government built 
a special plant at Edgewood with a capacity of 300 
tons of sulphur monochloride per day. 
As soon as toxic gas warfare had developed to a 
considerable extent, the perfection of gas-absorbing 
masks had given almost a complete protection 
against this new weapon, if the soldier put on his 
gas mask in time. But the mask, especially the 
earlier forms of it, was not easy upon the wearer, 
due to the difficulty of breathing through it and also 
because it restricted the soldier's vision. It was soon 
discovered that a force compelled to wear its gas 
masks for any considerable period lost in efficiency. 
The employment of gas by both sides for the pur- 
pose of forcing the opposite sides to wear masks 
continually was an important element in war at the 
close of hostilities. For this purpose the so-called 
tear gases were produced. Gassing the enemy with 
tear gas was much cheaper than with poison gas, yet 
it forced him to remain masked. The tear gases 
were highly effective. Even a trace of tear gas in 
the air would in a few moments blind a man tem- 
porarily. A single tear-gas shell could force the 
wearing of masks over an area so wide that it would 
require from 500 to 1,000 phosgene shell to produce 
the same effect. 
As most of the tear gases had bromine bases, it 
was early determined by the Government to increase 
the American supply of bromine for gas warfare 
requirements. The domestic source of bromine is 
principally in certain subterranean brines, these solu- 
tions containing bromine in its compounds. The 
Government financed the sinking of 17 brine wells GAS WARFARE 
23 
near Midland, Mich., where the brines are especially 
rich in bromine. This plant is a most valuable 
future war asset of the United States, capable of 
yielding approximately 650,000 pounds of bromine 
per year. The tear gas which the Government pre- 
pared to manufacture was brombenzyl cyanide, a 
brownish, oily liquid which solidifies to white or 
brownish crystals at 290 C. Its production involves 
a fairly intricate chemical process. The first step is 
to chlorinate ordinary toluol, one of the coal tar 
bases, to produce benzyl chloride. This chloride is 
then mixed with sodium cyanide in alcoholic solu- 
tion and distilled, benzyl cyanide being the result. It 
is then only necessary to brominate the benzyl cya- 
nide by treating it with bromine vapor. Bromine 
gases are not poisonous in the sense of being killers, 
but are merely highly irritating to the membranes of 
the eye. The killing gases are phosgene, chlorpicrin, 
and chlorine. Mustard gas in sufficient amount is 
also fatal, its effect being identical to that of a deep 
burn. It attacks the lungs, the eyes, the skin, and 
even the intestines if food contaminated with mus- 
tard gas is swallowed. One of its insidious features 
is the fact that its action is practically always de- 
layed. Goggles alone would usually be sufficient 
protection against tear gas, except for the fact that 
it is invariably mixed with the deadlier gases. 
The production of gases and other chemicals was 
only part of the work of the Edgewood Arsenal 
and its subsidiary plants. The other chief activity 
was that of filling artillery shell with the toxic sub- 
stances. The description of the plant which filled 
shell with phosgene will indicate the scale upon 
which this operation was conducted. The empty 24 
GAS WARFARE 
shell, after being inspected, were loaded on trucks, 
together with the proper number of loaded boosters. 
The booster was the device which exploded the shell 
and scattered the gas. Electric locomotives then 
pulled the shell trucks to the filling buildings. There 
were four of these to a single shell-filling plant, 
radiating at right angles from a common center. 
From the trucks the empty shell were lifted by hand 
to a belt conveyor and the conveyor carried the shell 
slowly through a room kept cold by artificial refrig- 
eration. Although the shell moved only 70 feet 
through this room the conveyor traveled so slowly 
that they were 30 minutes in transit, and during this 
time they were cooled to a temperature of about 
o° F. This chilling was necessary because phosgene 
has a low boiling point, and it was necessary to keep 
the temperature of the metal of the shell consider- 
ably below the boiling point of phosgene in order 
that the gas might remain in liquid form while the 
filling was going on. The chilled shell cases were 
next transferred to small trucks, each carrying six 
of them. The loaded truck was then drawn through 
a filling tunnel by means of a chain haul. This tun- 
nel was so ingeniously contrived that the human 
assistance to the filling and closing machinery could 
all be conducted from the outside. The phosgene, 
kept liquid by refrigeration, was run into the shell 
by an automatic filler. The truck was then moved 
forward a few feet to a point where the boosters 
were inserted into the noses of the shell by the hands 
of the operator reaching in through an aperture in 
the tunnel. The final closing of the shell was then 
accomplished by motors. The air in the filling tun- 
nel was constantly withdrawn by strong ventilation. GAS WARFARE 
25 
the exhaust air being washed in stone towers by 
chemical agents to neutralize any gases that might 
be present. The filled, inclosed shell were next con- 
veyed to a dump, where they were classified and 
then stood nose down for 24 hours to test them for 
leaks. Then they were painted, striped, and sten- 
ciled by air paint brushes. The final process was 
to pack them in boxes and store them for shipment. 
This was done in large storage magazines on the 
grounds of the Edgewood Arsenal. A similar meth- 
od was used for filling shell with chlorpicrin, except 
that refrigeration was unnecessary. 
Several filling plants were designed and con- 
structed for filling grenades with stannic chloride 
and with white phosphorus, and for filling incen- 
diary drop bombs. In this connection the table on 
page 26 is instructive: 
The following is a summary of the production 
and expectations of the Edgewood Arsenal: 
(1) The gas program as of March 1918, called 
for approximately 545 tons of toxic gas weekly. 
(2) The Chemical Warfare Service program of 
August 12, 1918, called for a much larger amount, 
viz, about 4,525 tons per week. 
(3) The approximate filling capacity of the Edge- 
wood Arsenal plant from August to November, 
1918, was nearly 1,000 tons per week. 
(4) The toxic gas production during this same 
period increased from 450 to 675 tons per week. 
(5) The capacity of all projectiles received, un- 
limited by boosters, varied during the same period 
from 125 to 450 tons per week. 
(6) The maximum capacity corresponding to 
boosters received was less than 100 tons per week. 26 
GAS WARFARE 
The Chemical Warfare production organization 
developed and manufactured a large number of spec- 
ial containers for the shipment of toxic gases. 
These were of special construction in order to guard 
against dangers that would result from leaks, and 
all had to stand the tests required by the Bureau of 
Explosives before they would be received for rail- 
Shell, Grenades, Livens Drums, and Drop Bombs Filled 
igi8 
75-mm. shell 
Grenades 
Livens 
drums 
Incendiary 
drop bombs 
Chlor- 
picrin 
Phos- 
gene 
Mus- 
tard 
oil 
White 
phos- 
phorus 
Tin 
tetra- 
chloride 
Phos- 
gene 
Mark 
I 
Mark 
II 
July 
62,866 
125.951 
110,358 
109,704 
IS.892 
1,988 
12 
9 
75,529 
79,272 
224 
8,696 
170,160 
51,421 
110,928 
98,948 
1,639 
56,763 
127,319 
147,669 
30,386 
August 
September.... 
October 
November.... 
Total 
Total number 
shipped over- 
seas 
1.738 
6,355 
12,026 
5.570 
350 
184 
8 
1,998 
100 
6 
424,771 
300,000 
2,009 
I5S.O25 
150,000 
440,153 
224,984 
363.776 
175,080 
25,689 
18,600 
542 
2,104 
Total Monthly Capacity of Filling Plants on Date of Armistice 
(Stokes Shell, Drop Bombs, and Other Special Con- 
tainers Not Included) 
75-mm. shell (ultimate capacity) 2,400,000 
4.7-inch shell 450,000 
155-mm. shell 540,000 
6-inch shell 180,000 
Gas grenades 750,000 
Smoke grenades 480,000 
Livens drums 30,000 
road shipment. The i-ton containers, all of which 
would hold i ton of liquid chlorine, were designed 
by the Ordnance Department and would withstand 
a pressure of 500 pounds per square inch. The 300- 
pound phosgene cylinders, designed by the Ordnance 
Department, were made to withstand a 500-pound 
hydrostatic pressure and a 250-pound air test. CHAPTER III 
Gas Defense Equipment, the Problem of Gas Masks, Box 
Respirator Equipment, Canister Ingredients, Carbon 
(Charcoal) for American Canisters, Horse Mask De- 
velopment, Production Data of Gas Defense. 
During the spring and summer of 1917 two 
marked tendencies were to be observed in the fight- 
ing in France. One of these was the greatly in- 
creased use by both sides of poisonous gases and 
chemicals, frightful in their effect; the other the 
almost complete censorship that hid the knowledge 
of this tendency not only from the people of Europe 
but particularly from those of the newest belligerent, 
America. The French and British Governments, 
who then controlled all news from the front, feared, 
and perhaps with reason, that if the picture of gas 
warfare, as it was then developing, should be placed 
before the American people, it would result in an 
unreasonable dread of gases on the part of the 
American Nation and its soldiers. 
The first masks adopted by the allies were simply 
gauze pads saturated with neutralizing chemicals. 
These became unsuitable as soon as new varieties 
of powerful poisons were brought out. The mask 
development thereafter progressed to the box re- 
spirator type. This consisted of a mask or helmet 
connected to a box filled with absorbing and neutral- 
izing chemicals which purified the air for the mask 
27 28 
GAS WARFARE 
wearer. This was the type of respirator in use to 
the end of the fighting. The first requisitions from 
the American Expeditionary Forces called for masks 
of two types, each soldier to be supplied with one 
of each. The reserve mask was to be of the gauze 
type and the regular mask of the box respirator 
type, affording protection from the more powerful 
poisons that were then just coming into use. 
The box respirator equipment, the general prin- 
ciple of which was finally adopted by all the nations 
at war, fell into two classes. In a single-protection 
mask the wearer breathed air from inside of the 
face piece, so that any leakage around the edges of 
the face piece would result in a casualty when the 
wearer was in a strong concentration of gas. The 
other sort, known as the double-protection mask, 
consisted of a gas-tight face piece, similar to that of 
the single-protection mask. In this type, to guard 
against any possible leakage around the edges be- 
tween the mask and the wearer's skin, the breathing 
system was sealed away from the air inside the face 
piece by means of a rubber mouthpiece and a nose 
clip, the wearer inhaling through the mouthpiece. 
The United States and English double-protection 
masks consisted of 11 principal parts as follows: 
i. A knapsack slung from the shoulder or neck. 
This contained the canister and a pocket for storing 
away the mask when not in use. 
2. A metal canister in which was contained the 
absorptive neutralizing chemicals. 
3. A flexible hose reaching from the canister to 
the face piece. 
4. A flutter, or exhalation, valve, which opened 
when the wearer exhaled his breath and closed when GAS WARFARE 
29 
he inhaled, thus bringing the inhalation through the 
canister but allowing the exhalation from the lungs 
to pass out without polluting the chemicals of the 
canister. 
5. The face piece, or hood, fitting snugly around 
the edges and covering the eyes, cheeks, lower fore- 
head, nose, mouth, and chin. 
6. The eyepieces, or lenses, through which vision 
was maintained. 
7. An elastic harness for the head, to hold the 
face piece in place. 
8. A body cord to tie around the chest and hold 
the knapsack firmly, so that the mask could be seized 
in both hands and pulled out of the knapsack. 
9. A metal flange connection or angle tube which 
carried the hose through the face piece to the mouth- 
piece. 
10. A rubber mouthpiece through which the 
wearer breathed and which helped to hold the mask 
in place. 
11. A wire nose spring and rubber nose pad to 
hold the nostrils shut and force breathing through 
the mouth. 
It was necessary to overcome many difficulties in 
the production of an effective mask. In the first 
place, the face piece had to fit perfectly and not leak 
gas around the edges. It had to fit into the hollows 
of the temples and give the jaws a free space in 
which to work, and yet not slip back and press 
against one's Adam's apple. The pressure of the 
mask on the forehead must come above the supra- 
orbital nerves which are just above the eyebrows, 
or else intense headaches will result from a few 
moments' wear. Moreover, to fit all faces and 30 
GAS WARFARE 
heads, several graduated sizes of masks are re- 
quired. The material of the face piece had to be 
gas-tight in itself. At first a fabric was made by- 
spreading rubber on cotton sailcloth; and, after test- 
ing it, it was found that the smallest molecule 
known, that of hydrogen, would not pass through 
it in large amounts. This seemed to be a suitable 
fabric, until tested by the newer gases. Then 
it was found that some of these gases were 
soluble in rubber compounds and could dis- 
solve their way through thin rubber so quickly 
that the face piece cloth offered practically no 
protection at all. Another difficulty with the 
rubber fabric was that it was likely to absorb 
and hold certain of the poisons, so that a man might 
be gassed by the mask itself. Experiment led to the 
discovery of a coating that would not only with- 
stand gas concentrations for a sufficient time, but 
would also aerate promptly and lose as much gas 
as it had absorbed. 
The eyepieces or lenses offered another problem. 
Celluloid is strong but it is not so transparent as 
glass. It ignites easily and is easily scratched. Glass 
is ideal in transparency and will not burn, but is 
fragile. Even so slight an accident as the breaking 
of a lens might cost a soldier his life by admitting 
concentrated gas to the mask. A material known 
as triplex glass was experimentally made. This 
consisted of a thin celluloid strip sandwiched be- 
tween two layers of glass, all three welded together. 
This glass would not splinter, and even if cracked 
or broken, would still be gas-tight. However, this 
had never been made in quantity and it was neces- 
sary to work out many kinks and to start a large GAS WARFARE 
31 
plant to provide the necessary millions of lenses. 
Then it was necessary to overcome the tendency 
of the eyepieces to dim, particularly in cold weather, 
as the wearer breathed moist breath into the mask. 
The answer to this problem was a soapy compound 
which put a slippery surface on the glass and 
avoided the droplets of mist. The first masks were 
also equipped with deep plaits so that the wearer 
could wipe off the lens with the interior of the face- 
piece itself, though the final development (the in- 
vention of a Frenchman by the name of Tissot) was 
to bring the cold air into the mask so that it flowed 
directly against the lenses and evaporated any con- 
densed moisture. This kept them clear under all 
ordinary circumstances. 
The metal tube passing through the face piece 
had to be free from pinholes and able to withstand 
rough handling without pulling loose. The harness 
had to maintain a gas-tight connection between, the 
wearer's face and the face piece, but not at the cost 
of pain or chafing of the face or head. The-flutter 
valve had to fit with absolute tightness and work 
perfectly and instantaneously at all times. The 
flexible hose leading from the canister1 to the face 
piece had to be strong and without flaws or leaks, 
and yet flexible in the extreme. A stiff hosei would 
be likely to swing and displace the face piece when- 
ever the wearer moved. The mouthpiece had to be 
comfortable and built along lines to prevent irrita- 
tion to the gums or lips, yet reinforced so that in his 
excitement the soldier can not bite down and shut 
off his air supply. The canister had to withstand 
corrosion and be gas-tight. Smooth sided canisters 
could not be used, for the gas would slip up the sides 32 
GAS WARFARE 
without coming in contact with much of the chem- 
ical filling. The sides of the canisters were, there- 
fore, ribbed so that' the charcoal and other ingre- 
dients working into- these- ribs baffled the gas and 
threw it out into the body of the chemicals. The 
canister, moreover, had to be equipped with a per- 
fectly' working check valve which would stop ex- 
halation through the canister and force the air to 
pass out through the flutter valve. The canisters 
were filled with charcoal and with cement granules. 
These were crushed into carefully sized small bits 
about the- size of a pinhead and packed in layers in 
the canisters. The air could pass through them 
easily and the particles of both substances absorbed 
gas. The chief quality requirements for the carbon 
and the cement were that they must have long life 
and great activity. Of the canister ingredients the 
charcoal offered the more difficult technical problem. 
During the winter of 1917-1918 the development 
of the mask continued and America designed her 
own typical mask-a gradual evolution, but one 
which, though based on the British design, arrived 
at a perfection which had been unknown in warfare 
before. The matter of rubberizing the face piece 
fabric was one of the most difficult problems to solve 
before proceeding in quantity production. Two 
methods of rubberizing cloth were in use. The first 
method was to roll out a thin sheet of rubber and 
then press it into the cloth fabric by running the 
whole thing under heavy rollers. This was known 
as the calender method. The other method, called 
the spreader method, was more intricate. In this 
process the sailcloth, tightly stretched, was carried 
around a roller. Above the roller a few thousandths GAS WARFARE 
33 
of an inch was a knife blade extending from edge 
to edge. The rubber compound in liquid form was 
then fed upon the roller in such manner that a thin 
film of it pressed under the knife blade and upon 
the cloth on the roller. The rubberizing method 
finally adopted was a combination of the calender 
and spreader methods. The rubber was applied 
green to the cloth. The curing process thereafter 
was hightly important. If the curing process were 
too short, the rubber would be sticky and would 
pull off the sailcloth too easily. If the rubber were 
overcured, it would crack and split. 
The story of the carbon (charcoal) which went 
into the American canister is one of the most inter- 
esting phases of the whole undertaking. Investiga- 
tions carried on by the research staff of the National 
Carbon Company, aided by a clue from the Univer- 
sity of Chicago, led to the selection of coconut shell 
as a raw material. Any carbon absorbs a definite 
number of times its weight of gas. Therefore the 
densest carbons will be most efficient, volume for 
volume, as gas absorbers in a given space. Coconut 
shells and other nut shells were found to be the most 
compact form in which carbon exists in nature in 
commercially practicable quantities, being consider- 
ably superior in this respect to anthracite coal and 
to such woods as ironwood and mahogany. An- 
other essential for charcoal used in the canisters was 
that it must be so hard that it would not crumble 
easily and produce dust that would clog up the air 
passages and prevent easy breathing through the 
canister. Coconut shell fulfilled both of these con- 
ditions better than any other known material. 
In further search for the ideal carbon experiments 34 
GAS WARFARE 
were made with almost every hard vegetable sub- 
stance known. Next to coconut shells, the fruit pits, 
several common varieties of nuts abundant in the 
United States, and several tropical nuts, were found 
to make the best carbon. Pecan nuts, and all woods 
ranging in hardness from ironwood down to or- 
dinary pine and fir, were found to be in the second 
class of efficiency. Among other substances tested 
were almonds, Arabian acorns, grape seeds, Brazil- 
nut husks, balsa, osage oranges, Chinese velvet 
beans, synthetic carbons, cocoa bean shells, coffee 
grounds, flint corn, corn cobs, cottonseed husks, 
peanut shells and oil shale. While many of these 
substances might have been used in an emergency, 
none of them would produce carbon as efficient, vol- 
ume for volume, as that of the coconut shells and 
other hard nuts. 
When we first began to build masks our demands 
for carboniferous material ranged from 40 to 50 
tons a day of raw material; but by the end of the 
war, due to vastly increased mask requirements, we 
were in need of a supply of 400 tons of coconut 
shells per day. This demand would absorb the en- 
tire coconut production of the tropical Americas 
five times over. It was equal to one-tenth of the 
total coconut production of the Orient. Since trans- 
portation from the oriental countries was out of the 
question on the scale demanded by our mask pro- 
gram, it was evident that we were likely to be seri- 
ously embarrassed by the lack of raw materials; 
and, indeed, at no time before September, 1918, did 
we have on hand a reserve supply of shells and other 
charcoal materials that would last for more than a 
few days, though at no time after the start was the GAS WARFARE 
35 
actual output of masks retarded by lack of these 
materials. 
A great branch of activity in securing carbon sup- 
plies was undertaken in this country. In the search 
for fruit pits and for domestic nuts it was found 
that the quantity of apricot pits, peach pits, cherry 
pits (largely from the canning industry), and walnut 
shells on the Pacific coast amounted to 23,600 tons 
annually. The United States arranged for the whole 
Pacific coast supply of these commodities and con- 
verted a part of a San Francisco plant of the Pacific 
Gas & Electric Company into a plant for the prelim- 
inary carbonization of 100 tons a day of these ma- 
terials. The next step was to turn to the consumers 
of the country and ask them to save their peach and 
apricot stones, their prune, plum, and olive pits, their 
date seeds, cherry pits, butternut shells, Brazil nut 
shells, and their walnut and hickory nut shells. The 
work of securing these and advertising the Govern- 
ment's need to the public was turned over to the 
American Red Cross. The Boy Scouts organized 
nut gathering parties. The Governor of Massachu- 
setts proclaimed November 9, 1918, to be gas mask 
day for the collection of carbon material, and 28 
other states fixed gas mask days in November. 
The procurement of the nuts, however, was but 
the first step in the production of carbon for use in 
the mask canisters, for after charcoal is first burned 
its pores are still filled with various impurities which 
may be summed up by the word "tar." When the 
charcoal was given a second heating, under careful 
temperature regulation, this tar was burned out, 
with the result that the charcoal itself became much 
more active in its absorption of gas. In fact, prop- 36 
GAS WARFARE 
erly activated charcoal is more than absorptive-it 
is catalytic in its action toward the gaseous poisons 
used in the war, not only absorbing them but has- 
tening their breakdown (digestion) into less injuri- 
ous substances. 
The activating of charcoal offered at the start 
considerably more of a problem than the question of 
making the charcoal itself, since activating had never 
before been conducted on a commercial scale. Two 
months of experimentation showed that the best 
distillation of shells and pits for charcoal was that 
conducted in illuminating-gas-making retorts. The 
activation thereafter had to be done in special equip- 
ment permitting of fine control of temperature. The 
Government eventually spent more than $1,000,000 
in a charcoal activating plant, providing for America 
the best protection known to science against the 
poisons which Germany had introduced into warfare. 
The cement granules, which also had tO' go into 
the canisters, supplied another problem. The basis 
of this cement was lime, to absorb gases of an acid 
nature. Portland cement was used, to give hardness 
and prevent disintegration and the formation of 
dust in the canister. Then infusorial earth was 
added, to make the compound porous in texture. A 
little sodium hydroxide was put in, to increase the 
alkalinity of the mixture. Finally there was an in- 
fusion of sodium permanganate, which is a powerful 
oxidizing agent. This latter chemical was added 
as a precaution against arsine. Arsine and arsenical 
compounds were difficult to use in warfare, but the 
Germans had introduced them to some extent, jus- 
tifying the United States in adding this protection. 
In making the granules the sodium permanganate GAS WARFARE 
37 
solution was mixed with the cement. The mixture 
was roughed out into slabs, allowed to set for three 
days, dried, ground up, screened to the proper size, 
and packed in drums for future use. The charcoal 
and cement were packed in the canister in alternate 
layers. The cement had the virtue of working while 
the carbon slept-that is, the carbon was active when 
there were gases present to be absorbed, but the 
cement kept on thereafter, digesting the gases which 
had been absorbed by the charcoal. 
Early in 1918, shortly before the German drive 
commenced, there was brought out in France a 
single-protection mask, that is, a mask in which the 
inlet tube entered directly into the space between 
the mask and the face, with the orifices so arranged 
that the fresh air was drawn across the eyepieces. 
This was known as the Tissot mask. The principle 
of the Tissot was correct as far as comfort was con- 
cerned, since it did away with the irritating mouth- 
piece, but the chief danger in this mask arose from 
the fact that it was made of thin, pure gum rubber. 
The United States endeavored to produce a mask of 
this type which should be gas-tight and yet rugged. 
In this work hundreds of experiments were made 
to determine face and head sizes and shapes. It is 
interesting to note in this connection that the size 
of a man's face has nothing to do with the size of 
his head, as large heads with small faces and small 
heads with large faces occur not infrequently. Two 
developments of the mask without mouthpiece or 
nose clip were made. One was known as the Akron- 
Tissot, or Type A-T, and the other, an improve- 
ment in the design of the Tissot mask, called the 
Kops-Tissot, or the Type K-T. In exact figures, 38 
GAS WARFARE 
up to the time of signing the armistice there was 
a total production of 5,692,499 masks of all types. 
Hand in hand with this procurement and manu- 
facturing achievement went the development of the 
technical section of the Gas Defense Division. In 
spite of this elaborate section, the testing of masks 
did not stop with it. There was a special field-test- 
ing section of the Gas Defense Division, composed 
of about 150 men who were trained to the minute 
in field maneuvers and did most of their work in gas 
masks. They were constantly in and out of gas 
with regular production and experimental masks, 
they played baseball in them, they dug trenches, laid 
out wire, cut wire, and fought sham battles at night, 
both with and without actual gas. The work of this 
section even went so far in the case of the later de- 
signs as to include a test where six men worked, 
played, and slept in the masks for an entire week, 
only taking them off for 30 minutes at each meal- 
time, and each day entering high concentrations of 
the most deadly gases, without any ill effects what- 
soever to the wearers. When it is remembered that 
eight hours was the limit of time which a strong man 
could wear the old-type mask, something of the ef- 
ficiency of the new mask may be realized. 
Investigation showed that a horse's eyes did not 
shed tears in the presence of even strong lachryma- 
tory gases. Moreover a horse never breathes 
through his mouth; and it was, therefore, necessary 
only to cover his nostrils. Furthermore, horses 
proved to be more resistant to the toxic gases used 
in Europe than were men, and his mask, accordingly, 
needed to be only a bag of many layers of chemically 
treated gauze. The following table is most inter- GAS WARFARE 
39 
esting and shows the number of respirators, canis- 
ters, horse masks, bleaching powder (tons), anti- 
dimming (tubes), sag paste (tons), dugout blanket 
oil (gallons), protective suits, protective gloves, dug- 
out blankets, warming devices, and trench fans man- 
ufactured during the European War. The dugout 
blankets were to be used at the doors of dugouts to 
make them gas proof. These were specially woven 
all-cotton blankets which were treated in France 
with a special heavy oil, shipped from the United 
Item 
Production 
Up to July 
i, 1918 
Up to Nov. 
11, 1918 
Dec. 31, 
1918 (total 
produc- 
tion) 
Respirators 
1,719,424 
5,276,515 
5,692,499 
Extra canisters 
507,663 
3,144,485 
3,189,357 
Horse masks 
154.094 
366.520 
377,881 
Bleaching powder (tons) 
'1,484 
3,677 
3,590 
Extra antidimming (tubes) 
2.85.5.776 
2,855,776 
Sag paste (tons) 
20 
1,136 
1,246 
Dugout blanket oil (gallons) 
95,000 
95,000 
Protective suits 
500 
2,450 
Protective gloves 
1,773 
1,773 
Dugout blankets 
159,127 
191,338 
Warning devices 
33.202 
45,906 
Trench fans 
11,343 
29,977 
50,549 
States. The protective suits and gloves were to 
safeguard men against mustard gas burns. The 
suits were made of oiled fabric and the gloves were 
of cloth impregnated with chemicals. The ointment 
known as sag paste was used to protect the skin 
against mustard gas burns. The gas warning sig- 
nals were of several types, watchmen's rattles and 
Klaxon horns being the most commonly used to 
sound the gas alarms. The trench fans were used 
for fanning out gas from trenches and dugouts. CHAPTER IV 
Tactical Employment of Gases, Importance of Gas as a 
Weapon in Military Operations. Lachrymators or 
Tear Producers, Density of Gases and Time of Ex- 
posure, Gases from Shells, Artillery Gas Zones of 
Dispersion, Effects of Temperature and Terrain. 
The introduction and development of the use of 
gas in military operations has had a marked effect 
on the action and employment of troops in combat. 
A proper tactical training now requires careful in- 
struction not only in measures of defense against 
gas, but in the use of gas against the enemy in of- 
fensive and defensive operations. Beginning in 
April, 1915, with the first successful use of gas in 
the form of a gas cloud projected from cylinders 
the forms and methods of use have been extended 
to include the use of the usual arms of combatant 
troops in the projection of gas and the employment 
of special arms for its projection. 
The general term "gas" as now used in warfare 
embraces all poisonous gases used in war, whether 
in cylinders, shells, or otherwise, and in addition, 
smoke, incendiary and irritating substances. The 
chemical substances designated as "gases" have a 
great variety of properties and effects. To think of 
all "gases" as having substantially the same proper- 
ties and tactical uses is a serious mistake. The 
"gases" used in warfare include not only true gases, 
but solids and liquids of widely varying properties, 
40 GAS WARFARE 
41 
that are converted in their actual use into "partic- 
ulate" gases and vapors. This makes possible a wide 
variety of tactical uses in combination with other 
means of warfare. The effect of gas persists after 
the explosion, imposing upon the enemy the neces- 
sity of wearing masks. This is a source of discom- 
fort and impairment of vision and efficiency. Gas 
is, moreover, capable of penetrating certain means 
of defense, such as trenches and dugouts, sometimes 
more effectively than other forms of ammunition. 
In order to realize the value of the employment 
of gas in military operations and the need of the 
measures of defense against gas, as well as to de- 
termine the conditions under which the use of gas 
is applicable, a knowledge of the physical properties 
and the physiological effects of gases and their be- 
havior upon release, is essential. 
The most important physical property is that 
which determines the "persistency" of the substance 
when used in the field. This property depends chiefly 
upon the rapidity of evaporation, which may be 
roughly estimated from the boiling point of the 
liquid. According to this criterion, we may name 
the following classes, giving the most prominent ex- 
ample of each: 
GROUP I-Substances which are gases at ordi- 
nary temperatures (of low per- 
sistency ) -Phosgene. 
GROUP II-Moderately volatile liquids (of mod- 
erate persistency)-Chlorpicrin. 
GROUP III-Slightly volatile liquids (of high 
persistency)-Mustard Gas. 
GROUP IV-Toxic smoke producers-Diphenyl- 
chlorarsine. 42 
GAS WARFARE 
Gases at ordinary temperatures (like phos- 
gene), when released from containers, will be blown 
about by the air currents; hence, if the air is rela- 
tively still, as when the wind is low, or in a dense 
wood, such a gas may persist for some time. On the 
other hand, in the open, and when the wind is blow- 
ing, it will be quickly dissipated. Such a gas can be 
used advantageously against positions to be at- 
tacked shortly after the release of the gas. 
Moderately volatile liquids (like chlorpicrin), 
when splashed upon the ground, will vaporize rather 
slowly, and will continue to contaminate the air in 
the neighborhood. In woods or in dugouts, or when 
the air is still, this contamination may persist for 
considerable lengths of time. However, that portion 
of the liquid which has vaporized is no more per- 
sistent than the gases in the phosgene group. 
The slightly volatile liquids (like mustard gas) 
will give off their vapors still more slowly, so that an 
infected area will remain dangerously infected for 
a greater length of time. However, it is difficult to 
get their vapors into the air in high concentrations. 
Only by breaking them up to form a mist can high 
concentrations and rapid deadly effects be realized. 
Substances of this class are accordingly especially 
useful in harassing an enemy and in preventing him 
from attacking over areas drenched with them. It 
has, in fact, been possible to ascertain positions 
which the enemy expected to attack by noting gaps 
left in territory otherwise heavily shelled with mus- 
tard gas. 
Toxic smoke producers (like diphenylchlor- 
arsine) are substances which can be made to give a 
suspension of extremely fine particles of poisonous GAS WARFARE 
43 
dust, or mists in the air. Such clouds are no more 
persistent than those caused by gases in the phosgene 
group. Their chief value lies in their ability to pen- 
etrate, more or less, the enemy masks. Usually 
when the cloud has settled upon the ground the 
amount of vapor given off is too small to have any 
toxic effect. Such effect is only produced by the 
inhalation of the particles themselves while sus- 
pended in the air. 
The toxic substances may be classified according 
to the predominant effects which they exert, with 
the understanding, however, that the action of any 
substance is not limited to a single tissue or group 
of tissues. Thus, a substance, the vapor of which 
causes injury to the respiratory passages, may, when 
applied to the skin, cause blistering. If the sole or 
chief usefulness of a substance in warfare depends 
upon its effect on the respiratory tract, it is classed 
as a respiratory irritant. If its power to produce 
casualties is due to its action on the skin, it is classed 
as a skin irritant. If both actions are useful, it is 
placed in both groups. By far the greatest number 
of substances thus far used injure the respiratory 
apparatus. Three groups may be differentiated: 
(a) Those which exert their chief effects upon 
the delicate membranes in the lungs through which 
oxygen passes from the air into the blood. The 
main result of this injury is to cause fluid to pass 
from the blood into the minute air sacs and thus 
to obstruct the oxygen supply to the blood. Death 
from one of these substances may be compared to 44 
GAS WARFARE 
death by drowning; the water in which the victim 
drowns being drawn into his lungs from his own 
blood vessels. Examples : Phosgene, chlorine, chlor- 
picrin, diphosgene. 
(b) Substances which injure the membranes 
which line the air passages. During normal life 
these membranes insure protection to the lungs 
against mechanical injury by particles which may 
be taken in with the air and against bacterial in- 
fection. As a result of the action of substances of 
this group their protective power is lost. Portions 
of the membrane may become swollen and detached 
and may plug up the smaller passages leading to the 
lung tissue, or the damaged tissue may become the 
seat of bacterial infection, thus setting up bronchitis 
and pneumonia. Examples: Mustard gas, ethyldi- 
chlorarsine. 
(c) Substances which affect chiefly the upper air 
passages, i.e., the nose and throat. These substances 
cause intense pain and discomfort but are not dan- 
gerous to life. They cause sneezing, painful smart- 
ing of the nose and throat, intense headache, a feel- 
ing of severe constriction of the chest, and vomiting. 
For varying periods after exposure they may cause 
general muscular weakness and dizziness, loss of 
sensation in parts of the body or even transitory 
unconsciousness. Examples: Diphenylchlorarsine, 
diphenylcyanarsine. 
Tear Producers (lachrymators).-Certain sub- 
stances have a powerful effect upon the eyes, caus- 
ing copious flowing of tears, followed by reddening GAS WAR'FARE 
45 
and swelling of the eyes, producing thereby effective 
temporary blindness. These effects are often pro- 
duced by extremely minute quantities of tear pro- 
ducing substances. Larger quantities of the same 
substances usually act as lung irritants as well. Ex- 
amples : Brombenzylcyanide, bromacetone, ethyl 
idioacetate, chlorpicrin. 
Skin Blisterers (vesicants).-Certain substances 
have a powerful irritating effect upon the skin, very 
much like that produced by poison ivy. The same 
effect is produced upon all the surfaces of the body 
with which the substance may come in contact, such 
as the eyes and the breathing passages. Accord- 
ingly, a substance producing skin blistering will, if 
inhaled, also act as a powerful irritant of the air 
passages. Example: Mustard gas. 
The following table includes the most important 
substances in use in Chemical Warfare, grouped ac- 
cording to persistency, with brief indications of 
their physiological effects. Little attempt is made 
to describe the odors, as this is very difficult. How- 
ever, all who have any responsibility in connection 
with Chemical Warfare, should become familiar 
with the various odors by actual experience: 
NAME 
PROPERTIES 
GROUP I-Gases at Ordinary Temperatures. 
(Readily dissipated by wind. Non-persistent.) 
Physical 
Physiological 
Chlorine (Berthollte) 
Greenish Yellow Gas. 
Lung irritant, death 
rapid or delayed. Less 
toxic than phosgene. 
Odor like that of 
bleaching lime. 46 
GAS WARFARE 
NAME 
Physical 
PROPERTIES 
Physiological 
GROUP I-Gases at Ordinary Temperatures. 
(Readily dissipated by wind. Non-persistent.) 
-Continued. 
Phosgene (C. G.) (Col- 
longite) 
Colorless gas, easily 
liquefied. 
Lung irritant, death 
rapid or delayed. Moul- 
dy odor. 
Nerve poison, immedi- 
ate death if concen- 
trated; very little effect 
if dilute. Rapid re- 
covery with no after 
effects. 
Hydrocyanic Acid (V. 
N.) (Vincennite) 
Colorless gas, easily 
liquefied. 
GROUP II-Moderately Volatile Liquids. (Mod' 
erately persistent.) 
Chlorpicrin (P. S.) 
Liquid less volatile than 
water. 
Lung irritant, slightly 
less toxic than phos- 
gene. Tear producer. 
Lung irritant. 
Diphosgene (S. P.) (Su- 
perpalite) (Green Cross) 
Dichlorethylarsine (Yel- 
low Cross 1) (New 
Green Cross 3) 
Liquid less volatile than 
water. 
Moderately volatile liq- 
uid. 
Nerve poison and res- 
piratory irritant. Pro- 
duces pain in throat, 
chest and head. 
GROUP III-Slightly Volatile Liquids. (Highly 
persistent.) 
Brombensylcyanide (C. 
A.). (Other tear pro- 
ducers similar in prop- 
erties and effect.) 
Mustard gas (H. S.) 
(Yperite) Dichlorethyl- 
sulphide. Yellow Cross 
Powerful tear producer. 
Liquid, boiling at 2170 
C. (4230 F.) Faint 
pungent odor when pure. 
Garlic odor from shell 
bursts. 
Air passage irritant, 
producing death, and 
skin blistering agent. 
Eyes and genital very 
sensitive. Effects often 
delayed 3 hours to 2 
days. 
GROUP IV-Toxic Smoke Producers. 
Diphenylchlorarsine (D. 
A.) Sternite, (Blue 
Cross). 
Solid, melting at 39° C. 
(1020 F.), boiling at 3330 
C. (632° F.) vapor con- 
densing to smoke. 
Similar to diphenylchlor- 
rarsine. 
Volatile liquid forming 
solid smoke with mois- 
ture of the air. 
Produces violent pain in 
head, throat and chest, 
with sneezing and cough 
ing. 
Same effects as D. A., 
but more powerful. 
Little toxic. Gives 
opaque cloud and pene- 
trates German mask, 
producing coughing. 
Diphenylcyanarsine. 
Stannic chloride (K. J.) GAS WARFARE 
47 
The degree of the physiological effects stated 
above depends on the time of exposure and the den- 
sity of the gas. It is evident that the more dilute 
the gas, the greater is the time of exposure necessary 
to produce an equally toxic effect. We may say 
roughly that doubling the concentration of a given 
gas reduces the time of exposure necessary to kill 
by at least half, and usually by more than half. 
This is very important in connection with tactical 
considerations, because the chief effectiveness of the 
gases of the non-persistent type, like phosgene, is 
attained through surprise-poisoning the enemy be- 
fore he is able to put on his mask. It is exceedingly 
important, from this standpoint, to surround him 
suddenly with gas of sufficient concentration before 
his mask is in place. 
The effectiveness of mustard gas is partly due 
to the fact that it retains its proportionate effective- 
ness at very low concentrations. The low concen- 
tration of one part in 100,000 acting for 20 minutes 
produces as much effect as the high concentration 
of one part in 10,000 acting for 2 minutes. This 
is also true to a large extent with chlorpicrin. On 
the other hand, the toxicity of hydrocyanic acid 
(the toxic constituent of Vincennite), falls off much 
more abruptly as the concentration diminishes, so 
that a dilution is very soon reached at which it can 
be breathed almost indefinitely with no bad results. 
When gas is liberated from a cylinder it is blown 
along the wind and as a result of the eddies set up 
by its passage over the surface of the ground, it is GAS WARFARE 
48 
mixed with air. The height of the cloud, when the 
ground is cool and the wind is not too high, is not 
very great, being limited largely by the height to 
which the eddies extend. Over smooth ground this 
amounts roughly to 30 feet at a distance of 100 
yards from the point of emission, increasing only 
slowly at greater distances. The cloud spreads lat- 
erally in the form of a fan. The angle of this 
spread may vary from 15 to 25 degrees. It is safe 
to take 20 degrees as an average. This means that 
the width of the cloud at any distance from the 
cylinder will be about 0.4 of the distance. An in- 
crease in this angle seems to be favored by de- 
creases in wind velocity and by increase in the rate 
of emission of the gas. It is possible for practical 
purposes, to calculate the concentration of gas in 
the cloud at varying distances from the cylinder pro- 
vided the velocity of the wind and the rate of emis- 
sion of gas are known. The concentration will be 
greatest in the middle, decreasing toward the edges. 
Increased wind velocity produces a proportionate 
decrease in the concentration of the cloud. The 
average concentration at any cross section of the 
cloud falls off somewhat more rapidly than the in- 
crease of the distance from the cylinder. Thus, if 
the concentration were one per cent at 50 yards, it 
would be somewhat less than 0.5 per cent at 100 
yards, and considerably less than 0.05 per cent at 
a thousand yards. If gas is emitted from the cylin- 
ders or groups of cylinders at a distance from each GAS WARFARE 
49 
other, each cloud will behave as above, but at the 
point where they begin to intersect dilution will be- 
come very slow. 
As the clouds formed from bursting gas shells 
proceed down the wind, the rate of speed is roughly 
the same as for the fan shaped cylinder discharge. 
Viewed from the side in elevation, these clouds are 
seen to spread out to a very great extent in the direc- 
tion of travel. This is due to the friction offered 
by the ground to the passage of the wind, that por- 
tion of the gas cloud closer to the ground being 
retarded the most. This longitudinal spreading of 
the cloud from a single shell burst causes it to dilute 
much more rapidly, as it proceeds from the point 
of emission, than does the cloud from a cylinder dis- 
charge. Of course, the retarding influence of the 
ground operates in both cases, but the continuous 
supply of gas from the cylinder tends to keep up 
the concentration. The result of artillery fire is 
usually a succession of distinct clouds, due to limi- 
tations in the rapidity of fire and to the dispersion 
of the shots. It is very important, therefore, that 
bursts should be as close as possible to windward of 
the target, in order to surround the target with 
clouds of the maximum concentration. Just as the 
behavior of the cloud from a single cyinder dis- 
charge enables one to predict the general behavior 
of the cloud formed by the simultaneous discharge 
of a number of cylinders, so the behavior of the 
cloud from a single shell burst, as outlined above, 50 
GAS WARFARE 
allows the prediction of the effect of gas shell fire 
in relation to wind, rates of fire and zones of dis- 
persion. 
When the gas shells are fired at a position the 
shells do not burst simultaneously. The zone of 
dispersion of a gun is the pattern produced upon 
the ground by the impact of a large number of shells 
from a single piece. This pattern is independent of 
the rate of fire. The individual gas clouds move at 
once with the wind from the points of burst, each 
growing and diluting. If, as is usually the case, the 
shells do not fall simultaneously the effective zone 
of dispersion becomes not a pattern on the ground 
but a pattern in the air elongated in the direction 
of the wind. This elongation has the effect of an 
increased dispersion, the increase being greater the 
greater the velocity of the wind and the less the rate 
of fire. Doubling the rate of fire will distribute the 
gas in roughly half the area, producing thereby at 
least twice the concentration and having far more 
than twice the effect in producing casualties. It is 
evident, also, that an increase in the wind velocity 
will distribute the gas over a larger area, decreasing 
the concentration of the cloud. 
One of the chief reasons for the effectiveness of 
gas is the fact that the cloud of gas is present for an 
appreciable length of time after its emission from 
cylinder or shell and is capable of producing casu- 
alties until the division becomes too great, or until 
it is blown away. Increased wind velocity reduces 
rapidly the length of time that gas remains in the GAS WARFARE 
51 
neighborhood. Gas is used most effectively in winds 
under 3 meters per second. However, too low a 
velocity is objectionable in the case of gas emitted 
near our own lines because of the possibility of a 
variation in wind direction bringing the gas back. 
Gas may be used in artillery shell fire at longer 
ranges even when the enemy is to windward by so 
adjusting the amount of gas used that the concen- 
tration will be harmless when it reaches our own 
lines. 
In order to kill a man with gas by surprise, it is 
necessary to surround him with gas so concentrated 
that the small amount he must breathe before get- 
ting his mask on is effective. After his mask is put 
on, the gas cloud is of relatively small effectiveness. 
Even when the enemy is wearing his mask, how- 
ever, it is desirable to subject him to gas of high 
enough concentration to penerate the mask, espec- 
ially the nearly exhausted ones likely to be in pos- 
session of many of the enemy's troops. 
When the ground is considerably warmer than 
the air, as when the sun is shining brightly, vertical 
currents of air rising from the surface of the ground 
are generally produced, which have a great tendency 
to dissipate gas clouds For this reason, gas is used 
far more effectively at night, or when the sky is 
overcast. 
It is very difficult to obtain a gas cloud, contain- 
ing more than 0.1 per cent, of gas, for more than a 
very short time after its release, and even this con- 
centration rapidly diminishes. Therefore, there is 52 
GAS WARFARE 
but little difference in physical behavior between a 
so-called gas cloud and so much air. Its density is 
but infinitesimally greater, and it is subject to the 
same movements as the surrounding air. If it stays 
longer in a valley than on higher ground it is chiefly 
because the winds blowing at higher elevations are 
not so strong in the valley. 
Features of terrain which affect the movement of 
the air affect the movement of gas clouds in almost 
the same way. Tall grass, bushes, trees, buildings, 
etc., retard the movement of air, and in an increas- 
ing degree they retard the movement of and retain 
gas clouds. In an attack following a gas bombard- 
ment, more time must be allowed if a field of grain 
is in the path than if short grass or ploughed fields 
intervene. Still more time is, of course, necessary 
where bushes or trees are present. CHAPTER V 
Tactical Use of Artillery Chemical Shell, Smoke Screen^ 
and Smoke Shell, Handling and Storage of Gas Shell, 
Transport and Storage of Gas Shell, Gas Shell 
Dumps and Batteries. 
The employment of gas is greatly influenced by 
earth forms, wooded and undulating ground having 
a very great influence on the result of a gas shell 
bombardment. The effect of topography is closely 
connected with atmospheric conditions, which it 
influences by altering the direction and force of air 
currents. Gases, being slightly heavier than air, 
tend to flow into gullies, draws and valleys, leaving 
the tops of hills free. In deep, narrow and long 
valleys, currents of air are usually found which 
carry the gas long distances. 
In hilly country special attention must be paid to 
deviations of the lethal wind from the general air 
current and to the mountain winds which in clear 
weather set in at certain periods of the day. A drift- 
ing of the gases from higher to lower places, such 
as obtains with attacks with gas projectors, cannot 
be reckoned with, for the gas density in the air is 
less in bombardments than in the spraying method. 
Gas may be used under intelligent direction in 
53 54 
GAS WARFARE 
nearly every character of terrain. It may be most 
satisfactorily used in almost level, slightly undulat- 
ing districts. 
Targets, such as woods, may be shelled with good 
results when the wind has too high velocity for tar- 
gets situated in open ground. When undulations in 
the ground are very marked, the fact that the wind 
is stronger on high ground than on low must be 
taken into account. High ground and open places 
must, therefore, receive a more intense concentration 
than those localities which are wooded or enclosed. 
During gas shell bombardments in open country, 
particular attention must be paid to the deviation 
of the local wind from the general wind direction 
and to air currents peculiar to the combined action 
of mountains and valleys, which occur on certain 
days in bright weather. That is, you must, if pos- 
sible, consider what the wind conditions are at the 
enemy position. 
With the long range of artillery, gas may be 
safely sent over to the enemy no matter what the 
direction of the wind. It is merely necessary to es- 
tablish safety zones, and knowing the character- 
istics of the gases available, deliver the gas where 
it may be needed in an effective dose, which at the 
same time cannot be blown back in dangerous quan- 
tities to our own line. To do this requires the abil- 
ity to make use of topographic maps and judge the 
effect of topography on prevailing winds. The Gas 
Officer cannot do good work without good topo- 
graphic maps. On each map which exhibits the GAS WARFARE 
55 
trench systems, he should mark the Gas Safety 
Zones and draw a wind circle six inches in diameter. 
This wind circle is divided into forty parts, called 
"Grads," numbered clockwise. 
The daily meteorological report gives the direc- 
tion of the wind by numbers. The wind blows from 
the circumference to the center of the circle, which 
represents the gun position. The o of the circle is 
north, io is east, 20 is south and 30 is west. In 
transmitting wind data, 50 is added to wind speeds 
to prevent confusion with the numbers which indi- 
cate wind direction. The speed is in meters per 
second. The artilleryman uses the wind circle to 
make meteorological corrections to his firing data. 
The Gas Officer uses the wind circle to study the 
probable effect of typography on the travel of a gas 
cloud impelled by the prevailing wind. The wind 
direction should be plotted on the maps. 
The Gas Officer should lay over his map each day 
a piece of transparent paper. On this he should 
trace the boundaries of the safety zone, a few of the 
heavier contours showing marked earth forms and 
also the bottom of all large depressions and the 
crests of all hills, indicating heights by figures. 
Across the hills and valleys he should draw in yel- 
low pencil parallel lines indicating the wind direc- 
tion. Mark in figures on these lines the speed in 
meters per second. Date each sheet and sign it. 
With the data thus ready, the Gas Officer can quickly 
decide just what gas to use on a certain target and 
the quantity. These sheets should be filed for record 56 
GAS WARFARE 
and the one used on the day on which gas is fired 
should accompany the report on the firing, a copy 
being retained at headquarters. 
In order to be able to allow for unexpected at- 
mospheric changes, the firing order should, if neces- 
sary, be given by pre-arranged signal visible at great 
distance; for instance, from a captive balloon. A 
similar signal is also to be decided upon in case 
break or cessation of the bombardment is necessary. 
The lighter the bombardments are, the more can 
these measures be modified. 
Two general types of bombardment with gas shell 
may be carried out. Variations and combinations 
of these two types should be often employed. The 
two general types are: 
Destruction Fire.-This type of bombardment is 
to be carried on with lethal shell, and is intended 
to produce casualties. Ordinarily, firing for more 
than two minutes at one time is not profitable, 
though in dead calm or thick woods and similar 
places, especially at night, the time may be extended 
to five minutes. Too much emphasis cannot be laid 
upon the fact that a gas attack must be executed 
with the greatest rapidity of fire and that the hits 
be close together, so as to create a solid gas cloud. 
Only in complete absence of wind may the rapidity 
of fire be decreased. In case of air currents, allow- 
ance must be made accordingly in the range finding. 
Gas effects at the objective must be obtained quickly. 
The necessary number of rounds is therefore to be 
distributed to as many batteries as possible. GAS WARFARE 
57 
Neutralizing Fire.-This fire is intended to lower 
the physical resistance, morale of the enemy, and 
to interfere with his activities, by causing him to 
wear his mask continuously, for a considerable time. 
This result can be obtained most economically with 
persistent gases. 
Heavy fire, or a very rapid rate of fire, with a 
persistent gas is not necessary. Since instantaneous 
lethal effects are not obtainable, a heavy burst of 
fire at the commencement of a bombardment is not 
required. After the desired concentration has been 
reached, it is only necessary to fire a small number 
of shell occasionally in order that this concentra- 
tion will be maintained. A sudden burst of fire with 
mustard gas amounting to i/io that for phosgene 
may be used to begin a bombardment. 
Counter-Battery.-This, as a rule, should con- 
sist of a burst of destruction fire, followed by a slow, 
neutralizing fire with a persistent gas. The final 
burst of concentrated fire with a lethal gas is often 
useful, if the neutralizing fire has been maintained 
for four or more hours. This final burst of fire 
should last for ten or fifteen minutes. Its purpose 
is to penetrate the enemy masks that have been ex- 
hausted by long continued wearing. 
Harassing.-This is solely a neutralizing fire, for 
the purpose of hampering enemy movements of ma- 
terial, and troops, and to cause exhaustion of per- 
sonnel through wearing the mask. Lachrymatory 
gases are used primarily for harassing effect. Any 
lethal effect obtained from those gases will be purely 58 
GAS WARFARE 
incidental, and they should not be used for this pur- 
pose, as the amount required would be abnormal. 
Where lethal effect is desired after lachrymatory 
firing, a bombardment with lethal shell may follow 
immediately. 
Blanketing.-This is a type of neutralizing fire 
which may be employed under especially favorable 
weather conditions. During a dead calm (at night) 
it is possible, with a comparatively small number of 
shell, to form clouds of gas which will lie in pools of 
fog, in hollows and valleys, for a considerable time 
after the shelling has ceased. If no wind arises, the 
enemy will have to wear his mask all night, or vacate 
the low ground. Non-persistent, lethal gases are 
useful in such cases. Caution: The objective must 
be far enough away from the friendly line to avoid 
danger from a slight drift of the clouds or from 
an adverse wind springing up. 
Interdiction Fire.-This is a type of neutralizing 
fire for the purpose of rendering important posi- 
tions untenable. This is best carried out by the use 
of mustard gas, unless our troops expect to occupy 
or pass over the area soon after the bombardment. 
Bombardment of Area.-In the bombardment 
of an area, which is essentially a question of neutral- 
izing fire, it should be noted that it is often advisable 
to open the fire with a burst of lethal shell on certain 
important targets in the area, and then to carry out 
the slow neutralizing fire. 
While attacking one front, a harassing and neu- GAS WARFARE 
59 
tralizing mustard gas bombardment can be effect- 
ively made on fronts, flanks, rear areas, and strong 
points not thus attacked. Troop concentrations, re- 
serves, artillery groups, lines of communication, 
villages, and extended areas which it is contemplated 
the advancing troops will not reach, may be attacked 
with mustard gas. 
When more than one objective is to be attacked 
for surprise effect with a lethal gas, the objective 
to the leeward of the wind is to be bombarded first. 
In this way the surprise effect on the second ob- 
jective is not lost. However, if fire on other targets 
is made soon enough so the wind will not carry 
gas to later targets before fire is opened on them 
this rule need not be applied. 
When harassing fire with a tear gas is to be used 
upon more than one objective, the objective to the 
windward should be first bombarded. When it is 
not considered practicable to attack a strong posi- 
tion by frontal assault the position may be rendered 
untenable for the enemy by shelling heavily with 
mustard gas, which will not interfere with sur- 
rounding or passing around the position. 
Barrages.-Gas shell may be employed in a bar- 
rage, in the following ways: 
(a) Accompanied by high explosives, under 
favorable weather conditions, gas tends to cause 
confusion among the enemy. About 25% of gas 
shell (1 gun per battery) should be used. While 
no danger to our own troops will occur from the 
use of this small percentage of gas shell, it will serve 60 
GAS WARFARE 
to deceive the enemy, causing him to wear his mask, 
and in this way hinder his activity. With a four 
mile per hour wind, men can follow within one 
minute. 
(b) May be used in "back" barrages, during an 
attack, to place enemy reserves and reinforcing 
troops at a disadvantage, by compelling them to 
wear masks. This is highly destructive to morale. 
Smoke screens have many times greatly aided in 
the execution of all sorts of operations, large and 
small, and it would seem that their use should be 
greatly extended. Smoke candles or grenades will 
always be used for the production of smoke, when 
their use is possible. Within the limit of their range 
trench mortars should be used. At greater distances 
artillery shell are a necessity. For all uses of smoke 
clouds, wind conditions must be carefully studied. 
There are two varieties of smoke shell in our 
service: White phosphorous (W. P.) shell, used 
only for screening purposes, and titanium tetrachlor- 
ide (F. M.) shell, used only for ranging purposes. 
The W. P. shell are not intended for ranging, but 
they can be used for this purpose when the F. M. 
shell is not available, provided certain corrections 
are made. Vice versa, the F. M. shell are not in- 
tended for screening purposes, although they may 
be used as such, if W. P. shell are not available. 
The F. M. shell will not give as dense and durable 
a cloud of smoke or as great a screening effect as 
the same size W. P. shell, hence it will be necessary 
to increase the number of F. M. shell used and the GAS WARFARE 
61 
rate of fire over the figures prescribed for establish- 
ing smoke screens with W. P. shell. 
Smoke may be used by the artillery (I) to blind 
enemy observation posts, machine gun emplace- 
ments, infantry or artillery, thereby screening-in in- 
fantry raids or other operations. (2) In order to 
draw fire and distract attention from another opera- 
tion. (3) To define the visibility limits of an attack 
or raid. (4) As a fake gas attack, or to make the 
enemy think a real gas attack is more extended. ( 5 ) 
In back areas to screen gun positions, etc. (6) Oc- 
casionally for burning effect against enemy troops. 
The number of smoke shell required to form an 
effective screen depends upon the considerations 
above enumerated. In winds much over 20 miles 
per hour it is practically impossible to form an 
opaque screen. The stronger the wind the further 
must be the source of the screen from the objective. 
Experiments have shown, however, that a screen can 
be formed even in a strong wind. The best wind for 
the use of artillery shell appears to be one having 
a velocity of about 14 miles per hour (6 meters per 
second), and blowing across the object to be con- 
cealed. 
One hundred yards per 10 feet per second of wind 
may be taken as a general guide as to the distance 
from the object at which artillery smoke shell should 
be placed. In hot weather particularly the smoke 
tends to rise from the ground, and there is, there- 
fore, a greater tendency for gaps to form in the 
screen. 62 
GAS WARFARE 
The effect of phosphorous shell of all kinds is 
cumulative, as the globules of phosphorus continue 
to bum on the ground from 15 to 20 minutes. As 
the cloud in the case of phosphorous projectiles is at 
its thickest soon after the bursts, it will be main- 
tained more evenly by adding small quantities at 
frequent intervals of time rather than by adding 
large quantities at greater intervals. 
No definite rules can be laid down as to the exact 
quantities of smoke shell required to form a screen, 
as the conditions will vary to a very large extent. 
However, as a general guide it may be taken that 
the following number of shell are required to form 
an adequate smoke screen under normal conditions: 
75 mm. shell, 2 rounds per 10 Yds. per Minute. 
4.7-inch shell, 2 rounds per 15 Yds. per Minute. 
155 mm. shell, 2 rounds per 25 Yds. per Minute. 
The above figures apply to the establishment of 
the smoke screen which may thereafter be main- 
tained by a reduced rate of fire, which should be 
controlled primarily by observing the behavior of 
the smoke screen. In general, it may be stated that 
one half the above rate of fire will effectively main- 
tain a smoke screen after it is once established and 
under normal conditions. 
The chief source of danger in handling gas shell 
is leakage, which can always be detected by the smell, 
or by the effect produced upon the eyes. All per- 
sonnel handling these shell should carry gas masks. 
The handling of shell under suspicion, and the res- GAS WARFARE 
63 
cue of any man affected by the fumes will be the 
duty of special detachments which should be detailed 
and trained for this purpose. If a leak is suspected, 
it should be reported immediately and all men work- 
ing in the vicinity should bring the respirator to the 
"alert" position. 
Leaking gas shell may be disposed of by burying 
them and by exploding them. 
Shell should be buried six feet deep and covered 
with a layer of chloride of lime before filling in the 
earth. They should not be fired from the gun. 
Spots where defective shell are buried should be in- 
dicated by sign posts driven into the ground and 
marked in an appropriate manner. Leaky shell can 
generally be detected by the smell of the gas. 
If there are large numbers of leaking shell, it is 
more satisfactory to explode them than to bury 
them, thus preventing the contamination of the area 
from a large number of buried shell. When gas pro- 
jectiles are to be blown up, they should be collected 
in lots so as not to exceed 100 lbs. of gas. Each lot 
should be exploded singly and another lot should 
not be exploded until the first gas cloud formed has 
disappeared. The gas cloud from one lot of this 
size is dangerous up to 500 yards' distance, and per- 
sonnel within that distance to leeward should be 
warned. The procedure for exploding the gas pro- 
jectiles is almost the same as that followed for ex- 
ploding H. E. and shrapnel. The projectiles are 
piled in a narrow ditch about 6 feet deep, and an ex- 
plosive or blasting charge is placed in the center of 64 
GAS WARFARE 
the lot and connected up to the blasting loads or 
time fuse. The lot is then covered with sand bags 
or other material to keep the metal pieces from scat- 
tering. The lot is then exploded. Then when the 
gas cloud has fairly well cleared, men wearing the 
respirators will fill in the holes, first covering with 
a layer of chloride of lime. Men working at de- 
stroying the blind gas projectiles should always wear 
the respirator from the moment they start to blast. 
Under no conditions should leaking shell be thrown 
into water. The necessity of careful handling of 
this sort of ammunition cannot be impressed too 
strongly. 
Wagons containing gas shell, on arrival at depots, 
will be opened by a gas non-commissioned officer, 
who will supervise the unloading and storage of 
shell. If the presence of a leaking shell is suspected 
in any wagon, the matter must be reported at once 
to the officer in charge. Such a wagon will then be 
unloaded by a special detachment wearing the re- 
spirator in the alert position. If possible, gas am- 
munition should be carried in trucks provided with 
shutters which should be left open. If closed trucks 
only are available, on arrival at the ammunition de- 
pot, or dump, the doors of both sides should be 
opened by a competent person and no one should be 
allowed to enter the truck until it is ascertained 
whether or not any gas has leaked. If, of neces- 
sity, open trucks have to be used, no tarpaulins 
should be put on. 
This ammunition should be stored in separate GAS WARFARE 
65 
bays and should be ventilated as well as possible, 
compatible with the exclusion of rain. If stored 
under tarpaulins, arrangements should be made to 
give access of air to the stack. Gas shell should be 
left in a cool place, as heat increases the internal 
pressure and the possibility of leaks. 
Buildings on or about the line between the gas 
area of the ammunition depot and the direction of 
the wind, must not be occupied during a raid. A 
messenger wearing a box respirator should be sent 
off to rouse sleeping men in such buildings and to 
see that the buildings are clear. If gas ammunition 
has been destroyed, it is forbidden to enter these 
buildings until they have been ventilated thoroughly, 
by men wearing respirators. All windows and doors 
of the building may be opened and wood fires burned 
in the center of the cellars. The building will be 
occupied only when declared safe by a gas officer 
or gas non-commissioned officer. 
At battery positions, gas shell should be piled in 
small dumps, the number in each being generally 
limited as follows: 
The 75 mm 100 
The 4.7-inch 50 
The 155 mm 25 
Dumps should preferably be located to the lee- 
ward of battery positions, according to the prevail- 
ing wind. If a direct hit occurs on a dump of gas 
shell, respirators will be put on immediately and 
without waiting for orders, and if possible a move 66 
GAS WARFARE 
will be made to the windward. All personnel of a 
battery will be kept constantly informed of the direc- 
tion of the wind. "Dud" gas shell, or gas shell 
debris, must not be touched until examined by a gas 
non-commissioned officer, who will attend to the 
proper disposal of the same. 
Mustard gas shell which show traces of leakage 
should be handled only by men who are protected 
with respirators and special gloves. Men detailed 
for such work should likewise be equipped with pro- 
tective clothing (if obtainable), whenever there is a 
possibility of the projectiles coming in contact with 
the clothes. 
As soon as the shell are received, they should be 
examined. Any indication of leakage at the gaine 
joint is a danger sign. (Masks and gloves should 
be worn.) Whenever possible, cases containing the 
shell should be stored in small piles in the open air. 
Near all such piles, a heap of earth and a supply of 
chloride of lime should be provided for covering any 
shell that may be burst by enemy fire. All storage 
depots should be supplied with shovels, and with 
chloride of lime in air-tight containers. 
If a mustard gas shell dump is reached by enemy 
fire, all personnel should move off to the windward 
and all men within 200 meters to the leeward should 
be warned. Broken shell should be covered with 
a layer of chloride of lime on top of which 6 inches 
of earth should be spread. During this work, masks 
and protective gloves should be worn. Undamaged 
shell of a small dump struck by a direct hit will not GAS WARFARE 
67 
be set apart for future use, but will be buried with 
the fragments of the damaged shell in a hole six 
feet deep and covered with a layer of chloride of 
lime before filling in. CHAPTER VI 
Chemical Artillery Ammunition, Construction of Gas 
Shell, Types of American Shell, Smoke Shell, In- 
cendiary Shell and Fuses, Fillings for Gun and How- 
itzer Shell. 
Gases for use in artillery shell are divided into 
three classes-non-persistent, semi-persistent, and 
persistent. The non-persistent gas, known as C. G., 
is most commonly used. It boils at + 8°C. (46°F.) 
and is lethal. In general, the non-persistent gases 
all have the same characteristics. They are all lethal 
and boil below -^2O°C. (68°F.) i. e., below normal 
atmospheric summer temperature. For this reason 
these gases change from liquids to gases without 
the aid of any artificial agency. When the shell is 
burst the liquid at once gasifies. Hence, the smallest 
bursting charge that will effectively open the shell 
is used. However, the bursting charge must be of 
sufficient strength not only to burst the shell, but 
also to check, to a large extent, the forward velocity 
of the base portion of the shell. Otherwise a con- 
siderable portion of the liquid will be cupped in the 
base portion of the shell and buried in the ground 
or carried by ricochet beyond the point of burst. 
In the employment of lethal gases, the main ob- 
ject is to produce a cloud of the highest possible 
68 GAS WARFARE 
69 
initial concentration which will drift down wind and 
completely envelop the object attacked. Such a 
cloud should consist of a highly concentrated nucleus 
when liberated from the shell. This will drift down 
wind and expand by lateral rather than upward en- 
largement. The formation of such a cloud requires: 
First, complete vaporization at the moment of lib- 
eration; and second, a bursting charge which will 
completely shatter the shell, but which is not so 
strong as to give undue dissipation of the liquid con- 
tents, particularly in an upward direction. It is es- 
sential that the bursting charge should break the 
shell completely into small fragments. The more 
rapid and complete the break-up, the more concen- 
trated is the cloud. Moreover, the loss of heat due 
to the sudden vaporization adds density to the cloud 
nucleus formed. 
The semi-persistent gases boil between -j-2o°C. 
and 4~2OO°C., i. e., above normal atmospheric tem- 
perature. With these gases to obtain a cloud nucleus 
of greatest possible concentration it is necessary to 
expel the liquid contents in a high state of atomiza- 
tion. This results in the most rapid vaporization 
with the least possible disturbance of the cloud. To 
secure this effect, the bursting charge should be of 
high power to insure maximum atomization, and yet 
not so high as to destroy the gas by dissociation. 
The object is to ensure that the liquid is converted 
into a cloud with least possible disturbance. This 
requires a more powerful bursting charge than the 
non-persistent gases and a shell of greater resistance. 70 
GAS WARFARE 
so that the liquid may be released under maximum 
pressure. 
In the case of the persistent gases, boiling above 
4-2OO°C. the object sought is quite different. Here, 
the cloud should be reduced to the minimum, and 
the area sprayed by the liquid contents of the shell 
increased to a maximum. This requires a large 
bursting charge of relatively high capacity but of 
slower action than the charge for the semi-persistent 
gases, and at the same time, a shell of relatively less 
strength than that required for complete atomiza- 
tion, but of sufficient resistance to give the maximum 
amount of coarse spray that will reach the ground 
as such. The charge which sprays the greatest area 
of ground and gives the minimum cloud is the one 
of maximum effectiveness. Due to their high boil- 
ing points, the persistent gases are relatively slow in 
their action, and hence prompt effects cannot be ob- 
tained unless the vaporization of the gas is secured 
by some artificial means. Such a means is a burst- 
ing charge developing high temperature and pres- 
sure, both of these conditions accelerating vaporiza- 
tion, the temperature acting directly and the 
pressure through increased pulverization. Conse- 
quently, if it is desired to obtain quick effect from 
persistent gases such as mustard gas, the shell should 
be loaded with a super-charge of high explosive, but 
it must be remembered that by so doing the gain 
in activity of the gas is obtained at the expense of 
greatly reducing its persistency. Another advantage GAS WARFARE 
71 
in providing mustard gas shell with a super-charge 
of high explosive is that they detonate with the noise 
and the shock of a true high explosive shell and 
thus disguise the fact that they are gas shell. Re- 
cent developments in the use of mustard gas have 
indicated that a portion, at least, of these shell 
should be provided with a super-charge of high ex- 
plosive to accelerate their action. If mustard gas 
shell having a super-charge of high explosive are 
used they will be stenciled with some distinguish- 
ing mark to indicate the fact that the bursting charge 
is above normal. 
In general gas shell are similar to high explosive 
shell. In fact, the majority of gas shell in use at 
the present time are converted high explosive shell. 
While the principles involved in the design of gas 
shell are radically different from those affecting high 
explosive shell, it has been considered desirable to 
simplify the manufacturing program by converting 
high explosive shell into gas shell. As the propor- 
tion of gas shell to high explosive shell increases, it 
becomes more and more important for gas shell to 
be specially designed. 
Gas shell consist of the shell body, which contains 
the gas; the gaine tube (adapter and booster casing), 
which screws into the nose of the shell and contains 
the bursting charge; and the bursting charge which 
consists of a small quantity of high explosive suffi- 
cient to open the shell, and in some cases, to atomize 
the liquid contents. Since most of the gases used 72 
GAS WARFARE 
enter the shell, as liquids, they expand as liquids 
when heated, and it is, therefore, necessary to leave 
a space for this expansion and only partially fill the 
shell. The void amounts to from 6% to 11% of 
the total capacity of the shell; depending upon the 
coefficient of expansion and the vapor pressure of 
the gas and the pressure which the joint between the 
shell and gaine tube will withstand. 
There are various methods of making these joints 
gas tight: 
(a) The general method employed by the Brit- 
ish to prevent leakage of gas into the gaine tube, is 
to make the adapter and gaine tube of one piece, 
so that there is no joint through which gas may leak 
into the gaine tube. To prevent the gas from leak- 
ing through the joint between the adapter and the 
shell body, the British paint the threads with cement, 
screw the adapter in, and then "spin" over the ex- 
terior of the joint between the adapter and shell. 
This joint is made before the shell is filled and a 
test pressure of 100 lbs. per square inch is applied to 
the shell, through the filling hole in the side of the 
shell, to test the integrity of the joint. The shell is 
then filled and the filling hole plugged up with a 
small tapered iron plug. 
(b) The French use, in some cases, a one-piece 
adapter and gaine tube. In other cases, however, 
the gaine tube is threaded into the adapter. The fol- 
lowing is quoted from a French document and shows 
the method of closing the joint between the adapter 
and shell body: GAS WARFARE 
73 
"To close this, we put in the first place between 
the bottom part of the head of the gaine and the 
machined shell, around the eye of the projectile, a 
pliable ring of lead tubing with a core of asbestos; 
in seating the gaine into the eye of the projectile, 
this ring is compressed and forms a dam between 
the head of the gaine and the throat of the eye of 
the shell. Furthermore, the threads are painted 
with a cement which is not attacked by the charging 
liquid and which in addition to stopping leakage adds 
very materially to the solidity of the union of the 
two parts." 
(c) In the present American models of gas shell 
the gaine tube is welded to the adapter, though it is 
probable that, for certain gases at least, this method 
will be abandoned for a one-piece adapter and gaine 
tube. The joint between the adapter and the shell 
body is made gas tight by means of a tapered or 
pipe thread. The adapter and gaine tube are 
screwed into the shell until the tapered threads bind 
tightly and produce a gas tight joint. To facilitate 
assembling, the threads on the adapter are lubricated 
with oil, but no cement is used; dependence for gas 
tightness is placed entirely upon the metal to metal 
contact between the threads. 
For certain gases, notably those containing bro- 
mine compounds, which have a corrosive action 
upon steel, it is necessary that the shell have a lining 
of glass or lead, and the gaine tube a coating of 
enamel, in order to protect the metal from the action 
of the gas. 74 
GAS WARFARE 
American chemical artillery shells are provided in 
the following calibers: 
75 mm. Gun, 
4.7" Gun, 
155 mm. Gun, 
155 mm. Howitzer, 
5" S. C. Gun, 
6" S. C. Gun, 
8" S. C. Gun, 
8" Howitzer, 
9.2" Howitzer, 
240 mm. Howitzer. 
These shell are with colored bands to denote the 
different types of gases, as follows: 
u. s. 
Symbol 
U. S. Markings Bands 
around Shell as Follows 
U. S. 
Symbol 
U. S. Markings Mi" Bands 
around Shelf as Follows 
D.A. 
i White 
B.A. 
i Red 
C.G. 
2 White 
C.A. 
2 Red 
P.G. 
I White, I Red, I White 
H.S. 
3 Red 
P.S. 
i White, i Red 
W.P. 
i Yellow 
N.C. 
i White, i Red, I Yellow 
F.M. 
2 Yellow 
Red Bands denote persistency. White Bands de- 
note non-persistency and lethal action. Yellow 
Bands denote smoke. Purple Bands denote incen- 
diary. The number of bands indicates the relative 
strength of the property indicated. Thus, three red 
bands denote a gas more persistent than one red 
band, and three white bands indicate a gas where 
lethal action is greater than one marked with only 
one white band. The body of the shell is painted GAS WARFARE 
75 
gray. The words "Special Gas" or "Special Smoke," 
as the case may be, are stenciled lengthwise of the 
shell in black block letters 5/8" high. Incendiary 
shell are painted gray, with the world "Special In- 
cendiary" stenciled lengthwise in black block letters 
5/8" high, but with no distinguishing bands. 
The table on the following page shows the 
amounts of each kind of chemical filling contained 
in the different calibers. 
With fixed ammunition (75 mm. and 4.7"), chem- 
ical shell are also marked on the base of the cart- 
ridge case by a black band 3/8" wide and the words 
"Special Gas," "Special Smoke," or "Incendiary," 
in 1/4" letters. The boxes in which chemical shell 
are packed are marked on each end with distinguish- 
ing bands and words used on the shell in addition 
to markings common to all artillery shell. 
The system of weighing and marking of chemical 
shell follow the general scheme employed with high 
explosive shell, i.e., each caliber of shell is divided 
into a number of different weight lots and marked 
on the 75 mm. by crosses just above the rotating 
band, on the 4.7" by squares just below the bourelet, 
and for calibers larger than 4.7", by squares on the 
ogive. In addition, for calibers greater than 4.7" the 
mean weight of the lot is stenciled on the shell, on 
6" shell just above the driving band and on other 
calibers on the ogive. 
In addition to the use of smoke shell for smoke 
barrages, these are used for ranging gas shell. Gas 
shell of the French, British, and Germans all have Time 
Calibers 
Mark 
Approximate 
weight of 
projectile less 
fuse and the 
filling in pounds 
The Approximate Weight of Shell Filling 
Gas 
Smoke 
H.S. 
C.G. 
N.C. 
P.S. 
C.A. 
B.A. 
F.M. 
W.P. 
Lbs. 
Lbs. 
Lbs. 
Lbs. 
Lbs. 
Lbs. 
Lbs. 
Lbs. 
Field 
Gun.... 
75 mm. 
II 
10.27 
1.35 
1.32 
1-74 
1-45 
i.97 
1.71 
1.90 
Gun.... 
4-7" 
II 
37.40 
4-38 
4-27 
5.62 
5.30 
4-44 
6.36 
5-53 
6.14 
How.... 
155 mm. 
II 
80.80 
11.30 
II .00 
14-50 
13.66 
12.18 
16.41 
1430 
15.85 
Gun.... 
155 mm. 
VII 
79-45 
11.30 
II .00 
14-50 
1366 
12.18 
16.41 
14.30 
15.85 
Gun.... 
5" 
VI 
42.84 
5.38 
6.70 
Gun.... 
6" 
III 
74-98 
10.50 
13.28 
How.... 
8" 
III 
169.75 
22.45 
22.01 
28.90 
27.20 
24.20 
32.67 
28.40 
31.50 
Gun.... 
8" 
III 
169.75 
22.45 
28.40 
How.... 
9-2 
252.45 
29.45 
28.69 
37.80 
35.62 
31.70 
42.78 
37.20 
41.30 
How.... 
240 mm. 
303.50 
37-50 
36.54 
48.20 
45.37 
40.40 
54-48 
47.40 
52 .6 
Of the fillings given in the above table it should be noted: N.C. is the same as P.S. except that it contains a stabilizer. 
B.A. and C.A. shell are both lachrymatory and can be used interchangeably, except that C.A. is several times more effective than 
B.A. 
F.M. and W.P. shell are both smoke shell. F.M. is a liquid, and F.M. shell are therefore primarily intended for ranging 
gas shell. W.P. is a solid and produces a dense and more persistent smoke than F.M., hence W.P. shell should be used primarily 
for smoke barrages and screens. 
76 GAS WARFARE 
77 
visible bursts, due to the presence of a smoke pro- 
ducing mixture in the shell. The French mix a 
"fumigene," or smoke producing compound, with 
the chemical filling. The British incorporate the 
smoke producing material with the bursting charge. 
The Germans produce a visible burst by use of a 
very large bursting charge. All of these methods 
reduce the efficiency of the shell and also have the 
disadvantage of producing a visible gas cloud whose 
limits are readily discernible by the enemy. All 
smoke producing compounds are omitted from 
American gas shell and the bursts are therefore, 
practically invisible. For ranging, therefore, it is 
necessary to have smoke shell of the same weight 
and ballistic characteristics as the gas shell. Smoke 
shell are first fired until the correct range has been 
ascertained, and then the fire for effect is continued 
with gas shell having invisible bursts. 
By far the best smoke producing material for 
smoke barrages and curtains is white phosphorus, 
and this is used in all smoke shell intended for bar- 
rage purposes. These shell are known as W. P. 
shell and are marked with one yellow band. How- 
ever, since phosphorous is a solid material, the W. 
P. shell is not accurate for ranging purposes, since 
shell filled with liquids (as all American gas shells 
are) have different ballistic characteristics and 
therefore different ranges from solid filled shell. 
For this reason it is necessary that smoke shell for 
ranging purposes be liquid filled. The best liquid 
smoke producing material is F. M. 78 
GAS WARFARE 
No satisfactory American incendiary shell has 
been developed as yet. The French have three cal- 
ibers of incendiary shell-75 mm., 120 mm., and 
155 mm. These are made from common high ex- 
plosive shell by replacing a part of the explosive 
charge by a number of special incendiary cylinders, 
known as Incendiary Cylinder Ml. 1878. The In- 
cendiary Cylinder Ml. 1878 consists primarily of a 
bundle of slow action quick match, tied with nitrated 
string, and internally and externally primed with a 
small quantity of ordinary quick match. This 
bundle is enclosed in a rectangle of cretonne cloth 
coated with an incendiary composition, and securely 
fastened with a heat-treated brass wire. The weight 
of the cylinder proper is 30 gr. and reaches 45 gr. 
when enclosed in a tar paper covering. On explo- 
sion of the projectile, the cylinder is ignited at both 
ends and projects 10 to 15 cm. fire jets for a period 
of 10 to 20 seconds, at the expiration of which time 
it burns, torch-like, for 70 to 80 seconds. Total 
combustion of the cylinder is, therefore, completed 
in approximately one and a half minutes. 
The action of all percussion fuses is started by the 
flash produced by the contact of a firing pin with a 
special detonator called a primer. This primer is 
filled with a very sensitive mixture of fulminate of 
mercury and other ingredients. The construction 
of all percussion fuses is such that the primer and 
the firing pin cannot come in contact until the shell 
is fired, and they are then kept a small distance apart 
until the shell or fuse touches the ground. Then GAS WARFARE 
79 
the firing pin and the primer are brought in contact 
in one of the following ways: 
(a) The firing pin may be attached to a movable 
plunger at the front end of the fuse and be forced 
back into the fuse the instant the plunger comes in 
contact with the ground. This will cause the firing 
pin to hit the primer attached to the fuse body. 
(b) The primer may be carried in a movable 
part inside the fuse. When the shell is checked by 
striking the ground the inertia of this movable part 
carries it on causing the primer to hit the firing pin. 
It is evident that the action described in (a) will 
bring the needle in contact with the primer as soon 
as the resistance of the* ground is sufficient to over- 
come the inertia of the plunger and force it into the 
fuse. It is, therefore, a quicker action than de- 
scribed in (b) which will take place only when the 
inertia of the shell itself has been overcome by the 
resistance of the ground. 
Fuses having the action described in (a) are 
called "super-quick." Only such fuses are suitable 
for chemical shell. It is essential that a chemical 
shell should burst above ground. A fuse whose ac- 
tion is not super-quick allows the shell either to bury 
itself, at least partially, or to ricochet before burst- 
ing. If the shell is even partially buried before 
bursting the effectiveness of a part of the contents 
of the shell is lost due to its soaking into the ground. 
If the shell ricochets before bursting, the gas may 
be carried beyond the target. 
Even with super-quick fuses, a certain amount of 80 
GAS WARFARE 
the effectiveness of the chemical shell is lost owing 
to the fact that the shell bursts at the ogive which 
leaves the base and part of the body more or less 
unbroken, and acts as a carrier for a certain portion 
of the liquid gases. If the angle of fall is low, the 
unbroken portion of the shell may ricochet and carry 
a portion of the gas past the target. If the angle of 
fall is great the unbroken portion will penetrate into 
the ground, thereby sealing its open end and pre- 
venting the liquid therein from being liberated. 
In order that a super-quick fuse may function, it 
must land on its point. If the angle of fall is small 
the ogive of the shell will hit the ground first, the 
shell may then ricochet before the point of the fuse 
can come in contact with the ground, and the fuse 
will not function. For this reason, and for the rea- 
sons given above, chemical shell should be fired with 
reduced charges whenever possible. This should 
not, however, be carried to the extreme of using ver- 
tical fire, as by so doing the dispersion is greatly in- 
creased and the unbroken base and body of the shell 
will bury part of the contents. 
Owing to the failure of super-quick fuses to func- 
tion at low angles, and the increase in dispersion 
and decrease in range (caused by the great length 
of such fuses) when used with small calibers of 
shell, the French use short fuses, which are not 
super-quick, in the 75 mm. It is a question whether 
the increase in dispersion is more desirable than the 
loss of effectiveness due to the comparatively slow 
action of the short fuses. GAS WARFARE 
81 
For smoke shell, when used for smoke barrages, 
and for gases such as mustard gas, it is sometimes 
highly desirable to have time fuses, allowing air 
bursts. With smoke shell air bursts permit the ad- 
justment of the dimensions of the smoke cloud and 
thus greatly facilitate the establishment and control 
of effective smoke curtains. With vesicant gases, 
air bursts allow a greater and more efficient disper- 
sion of the liquid contents. A combination fuse, 
combining a time element and a super-quick percus- 
sion element is now being developed, so as to enable 
batteries to conduct gas or smoke shoots with both 
ground and air burst. An effective combination fuse 
will also greatly reduce the number of duds, since 
its double action will cause the shell to explode on 
contact if it fails on time and vice versa. 
The following are types of fuses suitable to use 
with chemical shell. These fuses have advantages 
and disadvantages: 
French I. A. Model 1915,1. A. L. Model 1916, 
and U. S. Mark III.-The general functioning and 
construction of these three fuses are similar, the 
I. A. L. and the Mark III being successive modifi- 
cations of the I. A. All are super-quick fuses, func- 
tioning by means of a plunger in the front of the 
fuse being driven into contact with a fulminate of 
mercury primer. 
Arming.-The firing plunger is prevented from 
coming in contact with the primer during transpor- 
tation, and while the shell is in the bore of the gun, 
by means of two steel half collars which engage with 82 
GAS WARFARE 
a shoulder on the firing plunger and prevent its 
movement to the rear. Two half collars are held 
in place by being wrapped with a brass ribbon on 
the end of which is a third half collar. The ribbon 
being wound in a direction opposite to the rotation 
of the gun, tends to tighten as long as there is rota- 
tional acceleration. When rotational acceleration is 
over, centrifugal force throws the third half collar 
out, and unwinds the ribbon, releasing the inner half 
collars and freeing the firing plunger. The firing 
plunger is prevented from being forced to the rear 
during flight by a shear wire. 
Firing.-On impact the end of the plunger hits 
first and is driven into the body, shearing the shear 
pin, and impinging on the primer before the shell it- 
self has touched the ground. 
French R. Y. Model 1917.-This is a super-quick 
fuse and the following advantages are claimed for 
it over the I. A. L.: (1) It is safe, and (2) its shape 
is such as to produce better ballistic effects, and, 
therefore, less dispersion. 
Action.-The firing pin and primer cannot come 
in contact until both have moved. On "set back," 
the plunger moves to the rear until the head engages 
with the body of the fuse. It is then as far to the 
rear as possible, and it becomes necessary for the 
primer to move forward to come in contact with 
the firing pin. The primer cannot move forward be- 
cause the sleeve around the firing pin, at the bottom 
of which the primer is fastened, is engaged with the 
prongs of the upper half of the safety piece, which, GAS WARFARE 
83 
in turn, is prevented from moving forward by en- 
gaging with the body of the fuse. On "set back," 
the lower half of the safety piece moves to the rear, 
freeing the upper half and allowing the upper half 
to move to the rear, the prongs being forced out of 
the groove in the primer sleeve. The upper half of 
the safety piece continues to "set back" until 
the prongs catch in the lower groove. The 
upper half of the safety piece is thus farther down 
on the primer sleeve than it was before the gun was 
fired. 
After "set back" is over, and the velocity of the 
projectile begins to diminish, the inertia of the parts 
free to move causes them to "creep" forward. The 
upper half of the safety piece returns to its original 
position, carrying the primer sleeve and primer with 
it. The primer has thus moved forward in the fuse. 
At the same time the firing plunger "creeps" for- 
ward to its original position. On impact, the firing 
plunger is driven back to the position it had during 
the "set back." The primer, however, has moved 
forward, so that the firing pin now comes in con- 
tact with it. 
The cover over the head of the firing plunger is 
painted red, and should not be removed. 
French I Model 1914.-This is a fuse used ex- 
tensively by the French for 75 mm. gas shell. The 
head of this fuse is usually painted red, though on 
certain models it is painted yellow. It has not been 
generally adopted, as it is considered unsafe, unless 
used with extreme caution. 84 
GAS WARFARE 
French Schneider Model 1916.-This is a non- 
super-quick fuse used by the French for 75 mm. gas 
shell. It causes considerably less dispersion than the 
I. A. L., but it is not considered quick enough for 
gas shell. It should not be used with gas shell of 
caliber greater than 75 mm. and should not be used 
when any of the super-quick fuses are available. 
The head of this fuse is painted white to indicate 
non-delay action. For it to function it is necessary 
for the primer pellet to move forward so that the 
primer comes in contact with the firing pin. 
Modified British No. 106.-This is a fuse of the 
super-quick type and has only recently been adopted 
by us. It is suitable for all calibers and ranks next 
to the Mark III and I. A. L. fuses for chemical skill. 
American 75 MM. Common Steel Shell Mark 
II.-This shell is marked and painted as stated in 
the following table: 
Gases 
Used 
The Shell Is Painted Slate 
Gray with the Following 
W Bands Around the 
Body 
The Following Words 
Lengthwise on the Body. 
Approxi- 
mate 
Weight 
of Cases 
Pounds 
H.S. 
3 Red 
Special Gas 
1.36 
C.A. 
2 Red 
Special Gas 
1.46 
B.A. 
i Red 
Special Gas 
1.97 
N.C. 
i White, i Red, I Yellow 
Special Gas 
i-74 
C.G. 
2 White 
Special Gas 
1.32 
F.M. 
2 Yellow 
Special Smoke 
1.71 
W.P. 
i Yellow 
Special Smoke 
1.90 
The bottom of the cartridge case is marked with 
a black band 3/8" wide and the words "Special 
Gas," or "Special Smoke." GAS WARFARE 
85 
The weights of the shell are the same as for high 
explosive shell and are marked as follows: 
FROM 
TO 
Weight Mark Just 
Above Driving Band. 
Lbs. 
Oz. 
Lbs. 
Oz. 
IO 
II 
II 
0 
L 
II 
0 
II 
s 
+ 
II 
s 
II 
II 
H-1" 
II 
II 
12 
0 
~F" "I- 
12 
o 
12 
5 
+ + + + 
Immediately above the weight marks, and on the 
side of the shell opposite the words "Special Gas" 
are the letters 75-G. 
The following fuses are authorized for use with 
these shell: U. S. Mark III, French I. A. L., Model 
1916, French I. A., Model 1915, Modified British 
No. 106 (when issued), French R. Y., and French 
Schneider, Model 1916. 
French 75 MM, Steel Shell Model 1915.-The 
filling, marking, etc., of these chemical shell in com- 
mon use are enumerated in the following table: 
No. 
Filling 
U. S. 
Symbol 
Marking 
The shell is painted green with 
the following distin- 
guishing marks 
Weight of Gas 
in Pounds 
Approximate 
2 
Incendiary 
Incendiary 
Red Ogive, No. 2 on Ogive 
3 
Smoke 
W.P. 
Red Ogive, No. 3 on Ogive 
1.06 
5 
Collongite 
C.G. 
1 White band around body, No. 
5 on Ogive 
1.55 
7 
Aquinite 
N.C. 
1 Orange Yellow band around 
body, No. 7 on Ogive 
1.76 
9 
Martonite 
B.A. 
1 Orange Yellow band around 
body, No. 9 on Ogive 
1-34 
20 
Yperite 
H.S. 
2 Orange Yellow hands, No. 
20 on Ogive 
1.31 
21 
Camite 
C.A. 
1 Orange Yellow band No. 21 
on Ogive 
1.52 86 
GAS WARFARE 
On the ogive, immediately below the number of 
the mixture, are letters indicating its nature. With 
No. 20, "Yt" indicates Yperite dissolved in carbon- 
tetrachloride, and "Yc" indicates Yperite dissolved 
in monochlorbenzene. Immediately below these let- 
ters, the date and place of fillings are placed. "Aub'' 
for Aubervilliers, "Vis" for Vincennes, "P.Cx" for 
Pont-de-Claix. With the exception of No. 20 and 
No. 21, the above mixtures contain a percentage of 
opacite (stannic chloride) added to produce smoke. 
The numbers of the mixtures are also placed on the 
base of the cartridge case. The weight classification 
and weight marking of this shell are the same as the 
U. S. 75 mm. The same fuses are to be used with 
this shell as with the U. S. 75 mm. 
American 4.7" Common Steel Shell Mark II. 
-The painting and marking of these shell are as 
stated in the following table: 
Gases Used 
Shell Is Painted Slate Gray 
Approximate 
Weight of 
Gases, Lbs. 
With the Following Yi" 
Bands Around the Body 
And following 
Words Length- 
wise on the Body 
H.S. 
3 Red 
Special Gas 
4-38 
C.A. 
2 Red 
Special Gas 
4-44 
B.A. 
i Red 
Special Gas 
6.36 
P.S. 
i Red, i White 
Special Gas 
5-3 
N.C. 
i Red, i White, i Yellow 
Special Gas 
S.62 
C.G. 
2 White 
Special Gas 
4-27 
F.M. 
2 Yellow 
Special Smoke 
553 
W.P. 
x Yellow 
Special Smoke 
6.14 
The bottom of the cartridge case is marked with 
a black band 3/8" wide and the words "Special GAS WARFARE 
87 
Gas/' "Special Smoke" or "Incendiary." The 
weights of the shell are the same as for high explo- 
sive shell. 
The following fuses are authorized for use with 
this shell: U. S. Mark III, French I. A. L. Model 
1916, French I. A. Model 1915, Modified British 
No. 106 (when issued), and French R. Y. 
A 4.7" semi-steel shell Mark V has also been de- 
veloped which differs from the steel shell only in 
that the net capacity is reduced from 92.4 cu. in. 
to 90.9 cu. in. 
American 5-inch Common Steel Shell Mark 
VI.-The painting and marking of these shell are 
as stated in the following table: 
Gases Used 
Shell Is Painted Slate Gray 
Approximate 
Weight of 
Gases 
With the Following H" 
Bands Around Body 
And Following 
Words Longitu- 
dinal on shell 
H.S. 
3 Red 
Special Gas 
5-38 
F.M. 
2 Yellow 
Special Smoke 
6.79 
The following fuses are authorized for use with 
these shell: U. S. Mark III, French I. A. L. Model 
1916, French I. A. Model 1915, Modified British 
No. 106 (when issued), and French R. Y. 
A 5-inch semi-steel shell has also been developed 
which differs from the steel shell only in reduced 
capacity. 
American 6-inch Common Steel Shell, Mark 88 
GAS WARFARE 
III, for Gun.-The painting and marking of these 
shell are as stated in the following table: 
Gases Used 
Shell Is Painted Slate Gray 
Approximate 
Weight of 
Gases, Lbs. 
With the Following 
Bands Around Bpdy 
And Following 
Words Length- 
wise on Body 
H.S. 
3 Red 
Special Gases 
10.50 
F.M. 
2 Yellow 
Special Smoke 
13.28 J 
The following fuses are authorized for use with 
these shell: U. S. Mark III, French I. A. L. Model 
1916, French I. A. Model 1915, Modified British 
No. 106 (when issued), and French R. Y. 
A 6-inch semi-steel shell has also been developed 
which differs from the steel shell only in reduced 
capacity. 
American 155 MM. Common Steel Shell, Mark 
II, for Howitzer.-The painting and marking of 
these shell are as stated in the following table: 
Gases 
Shell;,Is Painted Slate Gray 
Approximate 
Weight of 
Gases, Lbs. 
With the Following J4" 
Bands Around Body 
And Following 
Words Length- 
wise on Body 
H.S. 
3 Red 
Special Gas 
ii.3 
C.A. 
2 Red 
Special Gas 
12.18 
B.A. 
i Red 
Special Gas 
16.41 
P.S. 
I Red, I White 
Special Gas 
13-66 
N.C. 
I Red, i White, i Yellow 
Special Gas 
14-5 
C.G. 
2 White 
Special Gas 
II .0 
F.M. 
2 Yellow 
Special Smoke 
14-30 
W.P. 
i Yellow 
Special Smoke 
15.85 GAS WARFARE 
89 
The following fuses are authorized for use with 
these shell: U. S. Mark III, French I. A. L. Model 
1916, French I. A. Model 1915, Modified British 
No. 106 (when issued), and French R. Y. 
A 155 mm. semi-steel shell has also been devel- 
oped which differs from the steel shell early in re- 
duced capacity. 
French 155 MM. Semi-Steel Shell, Model 1915, 
for Howitzer.-The following are the 155 mm. 
howitzer French chemical shell in common use: 
Filling 
U. S. 
Symbol 
Marking 
The Shell Is Painted Green 
with the Following Distin- 
guishing Marks 
Approximate 
Weight of 
Gas, Lbs. 
I No. 
Name 
Type 
Naud 
Incendiary 
Incendiary 
Red Ogive-I black ring.... 
•. • 
S 
Collongite 
C.G. 
i White band around body- 
No. 5 on Ogive 
9-0 
7 
Aquinite 
N.C. 
I Orange Yellow band around 
body-No. 7 on Ogive.. . . 
10.7 
9 
Martonite 
B.A. 
I OrangeYellow band around 
body-No. p on Ogive.... 
7-46 
20 
Yperite 
H.S. 
2 Orange Yellow bands- 
No. 20 on Ogive 
7.6 
21 
Camite 
C.A. 
I Orange Yellow band- 
No. 2i on Ogive 
8.83 
On the ogive, immediately below the number of 
the mixture, are letters indicating the nature of the 
mixture. With No. 20, "Yt" indicates Yperite dis- 
solved in carbontetrachloride, and "Yc" indicates 
Yperite dissolved in monochlorbenzene. 
Immediately below these letters are indicated the 
date and place of filling: "Aub" for Aubervilliers, 
"Vis" for Vincennes, and "P.Cx" for Pont-de- 
Claix. 90 
GAS WARFARE 
With the exception of No. 20 and No. 21, the 
above mixtures contain a percentage of Opacite 
(stannic chloride) added to produce smoke. 
American 155 MM. Common Steel Shell, Mark 
VII, for Gun.-These shell are the Mark II how- 
itzer shell, modified for use in the 155 mm. gun. 
They have two driving bands. 
Gases Used 
Shell Is Painted Slate Gray 
Approximate 
Weight of 
Gases, Lbs. 
With the Following 
Bands Around Body 
And Following 
Words Length- 
wise on Body 
H.S. 
3 Red 
Special Gas 
II .30 
C.A. 
2 Red 
Special Gas 
12.18 
B.A. 
i Red 
Special Gas 
16.41 
P.S. 
i Red, i White 
Special Gas 
13-66 
N.C. 
i Red, i White, i Yellow 
Special Gas 
14-50 
C.G. 
2 White 
Special Gas 
II .00 
F.M. 
2 Yellow 
Special Smoke 
14-30 
W.P. 
i Yellow 
Special Smoke 
15.85 
The following fuses are authorized for use with 
these shell: U. S. Mark III, French I. A. L. Model 
1916, French I. A. Model 1915, Modified British 
No. 106 (when issued), and French R. Y. 
A 155 mm. semi-steel shell has also been devel- 
oped which differs from the steel shell only in re- 
duced capacity. 
French 155 MM. Semi-Steel Shell, Model 1917, 
for Gun.-These shell are the model 1915 howitzer 
shell modified for use in the 155 mm. gun. They 
have two driving bands. 
The following are the 155 mm. howitzer French 
chemical shell in common use: GAS WARFARE 
91 
Filling 
U. S. 
Symbol 
Marking 
The Shell Is Painted Green 
with the Following Distin- 
guishing Marks 
Approximate 
Weight of 
Gas, Lbs. 
No. 
Name 
5 
Collongite 
C.G. 
i White band around body- 
No. S on Ogive 
9.0 
7 
Aquinite 
N.C. 
I Orange yellow band around 
body-No. 7 on Ogive.... 
10.7 
On the ogive, immediately below the number of 
the mixture are letters indicating the nature of the 
mixture. Immediately below these letters are indi- 
cated the date and place of filling "Aub" for Auber- 
villiers, "Vis" for Vincennes, and "P.Cx" for Pont- 
de-Claix. On the body are the letters G.P. in white, 
indicating that it is a gun shell. 
The above mixtures contain a percentage of 
Opacite (stannic chloride) added to produce smoke. 
The weight classifications and weight markings 
of this shell are the same as for the U. S. 155 mm. 
gun shell. 
The same fuses are to be used with this shell as 
with the U. S. 155 mm. gun shell. 
American 8-inch Common Steel Shell Mark 
III.-The same shell is used for both howitzer and 
gun, but only the H. S. and F. M. fillings are used 
in the gun. The painting and marking of these shell 
are as stated in the table on page 92. 
Immediately above the driving band are the letters 
"8-GH" indicating that the shell may be used in 
either the 8" gun or the 8" howitzer. 
The following fuses are authorized for use with 92 
GAS WARFARE 
these shell. U. S. Mark III, French I. A. L. Model 
1916, French I. A. Model 1915, Modified British 
No. 106 (when issued), and French R. Y. 
Fillings for Howitzer Shell 
Gases Used 
Shell Is Painted Slats Grat 
Approximate 
Weight of 
Gases, Lbs. 
With the Following W 
Bands Around Body 
And Following 
Words Length- 
wise on Body 
H.S. 
3 Red 
Special Gas 
32.45 
C.A. 
3 Red 
Special Gas 
24-20 
B.A. 
i Red 
Special Gas 
32-67 
P.S. 
I Red, I White 
Special Gas 
27.20 
N.C. 
i Red, i White, i Yellow 
Special Gas 
38.90 
C.G, 
2 White 
Special Gas 
22.05 
F.M. 
2 YeEow 
Special Smoke 
28.4 
W.P. 
i Yellow 
Special Smoke 
3i 5 
An 8" semi-steel shell has also been developed 
which differs from the steel shell in reduced capac- 
ity only. 
9.2-inch and 24o MM. Chemical Shell-These 
shell are both steel and semi-steel, and use the fol- 
lowing fillings: 
Gases Used 
Tse Shell Is Painted Slats Gray 
And the Following Words 
With the FoUowins W Bands 
Artxtnd the Body 
Lengthwise on the Body 
H.S. 
3 Red 
Special Gas 
C.A. 
2 Red 
Special Gas 
B.A. 
i Red 
Sped'-.'; Gas 
P.S. 
I Red, i White 
Ste-nal Gas 
N.C. 
i Red, I White, i Yellow 
Special Gas 
C.G. 
2 White 
Special Gas 
F.M. 
2 Yellow 
Special Smoke 
W.P. 
i Yellow 
Special Smoke 
These shell take the same fuses as are used with 
other calibers. CHAPTER VII 
Smoke for Military Purposes, Phosphorus and Tetra- 
chlorides, British "S" and B. M. Mixtures, Smoke 
Screens, Smoke Shell, Protection of Tanks. 
Phosphorus, tin, titanium, silicon and special 
smoke mixtures are commonly employed for produc- 
ing* smoke for military purposes. Phosphorus, 
when exposed to air, quickly produces great vol- 
umes of dense white smoke, the particles burning 
on the ground persisting for several minutes. Phos- 
phorus gives smoke of the highest obscuring power 
and greatest persistency of any of the smoke pro- 
ducing substances. The burning particles of phos- 
phorus make deep and serious burns in flesh and 
hence it has a decided value against troops exposed 
to it. Phosphorus is therefore used for smoke 
barrages and screens, in artillery shell, trench 
mortar bombs, and hand and rifle grenades. Tin, 
silicon, and titanium (tetrachlorides) are liquids 
which give smoke when liberated in the air. 
They are not as effective as phosphorus for 
smoke barrages and screens because their smokes 
have a smaller obscuring power and less persistency. 
They are, however, more abundant than phosphor- 
us and are in the nature of substitutes where phos- 
phorus cannot be obtained. These materials are, 
therefore, loaded as phosphorus substitutes into 
artillery shell, trench mortar bombs, and hand gre- 
93 94 
GAS WARFARE 
nades. Due to the fact that these substances are 
liquids, they are peculiarly suited for smoke ranging 
shell, as they exhibit the same ballistic characteris- 
tics as liquid gases. The relative merits of these 
three substances are as in the order named, and, 
as compared with white phosphorus, may be taken 
in the proportion of 2 to 5. 
Other smoke mixtures include the British "S" 
mixture, consisting essentially of saltpetre, sulphur, 
pitch, borax and glue, and the "B. M." mixture, 
consisting essentially of powdered zinc, carbon tet- 
rachloride, sodium chlorate and magnesium carbon- 
ate. The British "S" mixture has been used in 
smoke candles effectively and as compared with 
phosphorus has a screening value in the proportion 
of 1 to 5. The "B. M." mixture is often used as 
a substitute for phosphorus in hand grenades and 
smoke candles, and has an obscuring value equal to 
phosphorus and a relative persistency of about one- 
half that of phosphorus. 
Smoke is most commonly used by (1) Artillery, 
with smoke shell for distant smoke barrages and 
for ranging gas shell. (2) Infantry, with Stokes 
3-inch smoke bombs for smoke screens up to a range 
of 1,800 yards; with hand and rifle smoke grenades 
to protect advancing troops against machine gun 
nests, etc.; with smoke candles to conceal troop 
movements, etc. (3) Gas troops, with Stokes 4-inch 
smoke bombs for conducting special tactical opera- 
tions, often combining with use of gas; for establish- 
ing smoke screens of large dimensions up to a range 
of 1,000 yards. (4) Air service, with small smoke 
drop bombs used for training observers in bomb 
dropping, etc. GAS WARFARE 
95 
Smoke, when its use is carefully studied and un- 
derstood, will be found of great value in modern 
infantry tactics, as it confers many of the advan- 
tages which are to be gained by conducting opera- 
tions at night, while few of the disadvantages are 
present Use of smoke must be very carefully 
planned in order to avoid certain serious disadvan- 
tages likely to accrue under conditions unfavorable 
to its use or if smoke be improperly employed. 
Smoke screens may be employed with one or more 
of the following objects in view: 
(a) To mask known enemy observation posts: 
to conceal and protect the front and flanks of at- 
tacking troops from enemy observation; and to blind 
hostile machine guns. 
(b) As a feint to draw the enemy's attention 
to a front on which no attack is being made, so as 
to hold his troops to their positions and prevent them 
from rendering assistance to the sector attacked; in 
inducing him to expend ammunition needlessly and 
to put down a barrage in the wrong place. 
(c) In the case of a smoke cloud used offen- 
sively to simulate gas, with a view to lowering the 
enemy's morale and forcing him to use his gas 
masks. It may also be used to extend the front of 
a gas attack. To make this effective, gas should 
occasionally be mixed with smoke in order to im- 
press upon the enemy the belief that it is never safe 
to remain in a smoke cloud without wearing his 
mask. 
(d) In flat or open country to conceal concen- 
trations of guns and troops, and to screen roads, 
forming-up places and lines of advance; also to blind 
the flashes of a battery in action in view of the en- 96 
GAS WARFARE 
emy's observation posts and to hamper observation 
from the air. 
(e) To cover or hide the construction of bridges, 
trenches, etc., in the face of the enemy. 
Ground and troops behind smoke screens can sel- 
dom be concealed from hostile airplanes or kite bal- 
loon observation. 
If troops are hidden in smoke clouds such clouds 
attract the enemy's fire and are therefore dangerous; 
for this reason, smoke screens intended to conceal 
concentrations should normally be formed at some 
distance-about 400 yards-from the object to be 
concealed. 
In frontal screens, care must be exercised to place 
the screen so that an enemy barrage laid on it will 
not catch advancing troops. Such a screen should 
preferably be placed on the enemy trench system. 
The necessity for anticipating the effect which a 
smoke cloud will have in impeding our own observa- 
tion and artillery fire should be considered, as well 
as the possibility of troops being hidden from our 
contact patrol airplanes. 
When smoke is liberated on the flank of an as- 
sault, care should be taken, by defining permissible 
wind limits beforehand, that the cloud does not pass 
across the front of the assaulting troops, as the lat- 
ter attacking through smoke are very liable to lose 
direction. 
When the use of a smoke screen in operation is 
contemplated, the enemy should be educated to as- 
sociate such a screen with some object other than 
the real one, e. g., he may, by means of a practice 
smoke screen, followed by no action, be led to sup- GAS WARFARE 
97 
pose that the object of the demonstration is to com- 
pel him to expend ammunition uselessly. 
It is obvious from the foregoing that it is of the 
utmost importance that the use of smoke should 
be systematic but varied instead of casual and hap- 
hazard. Initiative at the critical moment means the 
saving of valuable lives and the avoidance of delay 
in the progress of the attack. If this is to be cul- 
tivated, and if misuse and waste are to be prevented, 
the most careful training is required, not only of the' 
individual, but also of companies, battalions, and 
even brigades. 
The amount of smoke-producing material re- 
quired to form a screen depends on a number of 
considerations, the most important of which are as 
follows: (a) The extent of the screen. As a 
rough guide it may be assumed that the width of 
the screen should be from two to three times the 
width of the object to be concealed (as seen by ob- 
servers from the points from which it is intended to 
prevent observation), (b) Duration of the screen, 
(c) The direction of the wind. A cross wind re- 
quires, as a rule, less expenditure of smoke than one 
at right angles to the front; and the difficulty of con- 
cealment increases if the direction of the wind is 
variable, (d) The velocity of the wind. The 
density of the smoke cloud diminishes considerably 
in proportion as the velocity of the wind increases. 
In a wind of over 20 miles per hour it is very dif- 
ficult to form an opaque screen without excessive 
expenditure of material. (e) The number of 
directions from which the enemy can observe the 
object or area to be concealed. The greater the num- 98 
GAS WARFARE 
ber of points from which an object can be observed 
by the enemy, the greater will be the extent of the 
screen required and therefore of the amount of 
smoke producing substances necessary to form it. 
(f) The distance of the object from the enemy's 
observation posts. The greater this distance the 
more effective the smoke cloud will be. 
In forming a screen with any form of smoke pro- 
ducer, it is necessary for the formation of the 
smoke screen to be very carefully organized, so that 
the best results may be obtained with the greatest 
economy of material. All personnel required for 
providing smoke screens should be trained before- 
hand in the use of the actual material which is to be 
employed and a simple rehearsal is most valuable. 
The program which is to be followed should state 
in detail the rate of expenditure of the smoke pro- 
ducing substances and should be given in writing 
to the personnel at each smoke source. 
Since the enemy artillery is the most dangerous 
adversary of the tanks, one of the vital conditions 
for the successful operations of tanks is blinding 
the ground observation posts which look out on the 
field of attack by means of a very dense well regu- 
lated smoke screen. In front of the artillery in 
position, a natural or artificial fog is a necessity to 
the tanks. Batteries assigned to support infantry, 
especially when latter is supported by tanks, and ar- 
tillery assigned to direct support of tanks should 
have on hand at all times a sufficient supply of smoke 
shells to take prompt advantage of opportunities for 
its use. The efficacy of smoke screen properly 
placed in assisting tanks to accomplish their mission 
has been amply demonstrated in action. GAS WARFARE 
99 
Smoke shells should not be employed in the roll- 
ing barrage alone. In different sections, notably 
that just cited, the method of forming a "smoke 
cage," or box barrage, gave excellent results. This 
method consists in establishing a smoke barrage on 
all points from which the objective to be taken could 
be seen at a distance of 500 to 600 meters. An en- 
closed area is thus formed in which the infantry and 
tanks may operate, screened from the view of the 
enemy observers, without themselves being bothered 
by lack of visibility within combat distance. 
Gas and smoke, during a withdrawal or on sta- 
bilized fronts, should be used according to the direc- 
tions given. On a retirement maximum amounts of 
mustard gas should be used from close up to the 
retiring troops to as far back as the longest range 
guns will reach. CHAPTER VIII 
Chemical Weapons for Use by Infantry, Incendiary Gre- 
nades, Thermit Hand Grenades, Tactical Use of Gas 
Grenades, Tactical Use of Smoke Grenades, Smoke 
Candles, Stokes Mortar Smoke Bombs. 
The following types of chemical weapons have 
been approved for use by infantry : Incendiary gre- 
nades, gas grenades, smoke grenades, smoke candles 
and 3-inch Stokes mortar smoke bombs. The in- 
cendiary grenades include the French "grenade-in- 
cendiaire a Main" and "U. S. Thermit hand gre- 
nade, Mark I." The gas grenades include the 
"French Suffocante et Lachrymogene" hand gre- 
nade, British "No. 28, Chemical Hand Grenade, 
Mark II," and U. S. "Gas Hand Grenade, Mark 
II." The smoke grenades include the French "In- 
cendiaire et Fumigene" Hand Grenade, the British 
"No. 27 Hand or Rifle Grenade, Mark I," and 
U. S. "Phosphorus Hand Grenade, Mark II." The 
smoke candles include the British "Smoke Candle, 
Mark I (L) Type S," the British "Smoke Candle, 
Mark II (L) Type S-l," and the U. S. "Smoke 
Torch, Mark I." The 3-inch Stokes mortar smoke 
bombs are manufactured in the United States and 
contain approximately three pounds of white phos- 
phorus or its equivalent. 
French "Grenade-Incendiaire a Main."-This 
grenade consists of a cylindrical shell of tin plate to 
100 GAS WARFARE 
101 
which the top and bottom are attached by crimping 
and soldering. In the cover is a hole into which is 
soldered a metallic ring, tapped to receive the firing 
mechanism. It has a percussion cap provided with 
a Bickford fuse, and carries a charge of thermit with 
a mixture of special ignition material. The gre- 
nade body is approximately 5 7/8" long and 2 1/2" 
in diameter. The total weight of the charged gre- 
nade is about 750 grammes or 1.65 pounds. 
Method of Use.-Hold the grenade in the hand, 
grasping the body firmly, and with the other hand 
remove the cover cap. Force the striker in sharply 
by striking it a keen blow against a hard body such 
as the heel, a rock, the butt of the gun, etc. The 
grenade takes fire in five seconds after the percussion 
and bums without exploding. 
Action.-The percussion of the primer ignites the 
Bickford fuse. Its combustion requires five sec- 
onds, after which the quickmatch is lighted. This, 
in turn, ignites the special igniting mixture. By 
reason of the delay and absence of explosion the 
grenade can be placed by hand, or thrown to a dis- 
tance. 
U. S. Thermit Hand Grenade Mark I is an ex- 
act duplicate of the French "Grenade Incendiaire a 
Main." This grenade is effective because of the in- 
tense heat of the molten material. It should be 
placed above the object to be burned and not under- 
neath it. It is placed by hand and used principally 
for the destruction of non-combustible material. It 
contains a thermit mixture which produces an ex- 
ceedingly high temperature, the contents becoming a 
mass of white-hot molten metal. It is used by raid- 
ing parties, where a permanent advance is not con- 102 
GAS WARFARE 
templated, for the purpose of destroying enemy 
trench mortars, machine guns, etc., which cannot 
be brought back to our own lines. The incendiary 
grenade is ignited and dropped down the muzzle 
of a mortar or placed in contact with some vital part 
with the result that the gun is ruined. A few men 
in each raiding party should be taught how to use 
these grenades. 
In destroying tanks of gas or oil, it is necessary 
to increase the time of burning of the fuse. In such 
cases, to give the operators time to reach a place of 
safety, it is necessary to replace the cap by a piece 
of Bickford fuse of the desired length which can 
be fired with a match. For this substitution make a 
tube out of paper through the center of which the 
fuse is passed. Bind it with a thread to the collar 
of the grenade and then to the cord. xAvoid getting 
the material wet during the operation. 
Grenades which have not taken fire can be picked 
up without danger and used again after having 
changed the fuse. 
French "Suffocante et Lachrymogene" Hand 
Grenade.-This grenade consists of the following 
parts: The body of the grenade, the collar, the 
gaine, and the automatic firing mechanism. The 
grenade is filled with "Papite" (acrolein), a liquid 
gas that is both lethal and lachrymatory. The body 
of the grenade is the same as the French "Grenade- 
Incendiaire et Fumigene, Mie. 1916 Automatique" 
with the exception that there is an orifice in but one 
end. This orifice is for the reception of a brass col- 
lar which is inserted therein and soldered to the 
body of the grenade. The collar is threaded inter- 
nally for the reception of a hollow brass plug which GAS WARFARE 
103 
is screwed into it and thus secured in the grenade. 
The gaine, made of tin, is soldered to the lower part 
of the hollow brass plug and carries the detonator, 
which is the bursting charge of the grenade. A rub- 
ber washer placed between the top of the collar and 
the shoulder of the plug forms a liquid tight joint. 
The hollow brass plug is threaded internally to re- 
ceive the automatic firing mechanism. A leather 
washer is inserted between the top of the hollow 
brass plug and the shoulder of the automatic firing 
mechanism to form a tight joint. The total weight 
of the charged grenade is 400 grammes or 0.9 
pounds. 
Method of Use.-Hold the grenade in the throw- 
ing hand, the firing mechanism up, in such a man- 
ner as to secure the lever. Pass the index finger of 
the free hand through the ring and withdraw the 
safety pin. The grenade is now armed and the 
bomber must take every precaution not to release 
the grip on the lever until the grenade is thrown. 
The grenade bursts five seconds after the action of 
the automatic firing mechanism, and produces a 
cloud of fine particles, intensely irritating to the 
respiratory passages. This causes violent coughing, 
and does not kill or seriously injure, but has con- 
siderable moral effect. 
Action.-After being thrown, the lever, which is 
no longer held by the safety pin, is projected from 
the grenade by the bolt. The removal of the lever 
permits the functioning of the automatic firing 
mechanism which sets off the primer. The primer 
ignites the slow fuse, which, after five seconds fires 
the denotator, exploding the grenade. 
British No. 28, Chemical Hand Grenade, Mark GAS WARFARE 
104 
II.-This grenade consists of the following parts: 
The body, the gaine, and the firing mechanism. It is 
filled with K. J. (stannic chloride). The body is 
made of cast iron, spherical in form and 3 3/8" 
in outside diameter. A boss is cast on the body 
through which is tapped a hole for the reception of 
the gaine. The gaine or denotator sleeve is also 
made of cast iron, on the open end of which is pro- 
vided an externally threaded boss for the assembly 
of the firing mechanism, which is similar in construc- 
tion to that used on the British "Grenade, Hand or 
Rifle, No. 27, Phosphorus, Mark I." 
Method of Use.-When used as a hand grenade 
its manipulation is the same as the British No. 27. 
The effect of the grenade is essentially the same as 
the French "Grenade-Suffocante et Lachrymogene, 
Mie. 1916, Automatique." 
U. S.-"Gas Hand Grenade, Mark II." This 
grenade is the same as the French "Suffocante et 
Lachrymogene" hand grenade. 
Method of Use.-The method of using the U. S. 
"Gas Grenade Mark II," is entirely similar to the 
French "Grenade-Suffocante et Lachrymogene, Mie. 
1916, Automatique." 
Action.-The grenade and lever are firmly 
grasped in the throwing hand in such a manner as to 
secure the lever. The safety split pin is removed 
with the free hand and the grenade is ready to 
throw. The thrower must take every precaution not 
to release the grip on the lever until he throws the 
grenade. Upon release of the lever, the striker im- 
pelled by its stiff spring rotates around the hinge pin, 
forcing up the lever, and strikes the primer, first per- 
forating the tinfoil disc which is sealed over the top GAS WARFARE 
105 
of the cap to waterproof the primer. The end of the 
fuse is tipped with a priming powder composition, 
which ignited by the primer in turn ignites the fuse. 
In five seconds the flame from the fuse spits into 
the fulminate composition of the detonator causing 
it to explode. The explosion of the detonator is 
sufficient to burst the body of the grenade and scat- 
ter the contents in all directions. 
Gas grenades are intended for the use of "mop- 
ping up" parties in driving the enemy out of dug- 
outs. This is generally more effective than blowing 
in the dugout with a charge of high explosive. A 
cloud is formed which violently attacks the eyes, 
nose and throat and penetrates to a large extent the 
enemy respirator. While not fatal, the fumes are 
unbearable in a close space, and the enemy is forced 
to come out choking and blinded. Four or five gre- 
nades should be carried by two men in each squad 
of a "mopping up" party. Upon coming to an 
enemy dugout, which is suspected of being inhab- 
ited, three or four grenades are tossed inside the 
entrance without exposing the grenadiers to fire 
from below. Occasionally they may be found of 
value in driving the enemy from a machine gun nest 
or strong point, when such a position is located 
downward. 
French "Incendiaire et Fumigene" Hand Gre- 
nade.-This grenade consists of the following parts 
The body, the gaine, and the automatic firing 
mechanism. The body, ovoid in form, is nine cen- 
timeters long, and six centimeters in diameter, at 
the center. It is made of two ovigal caps of tin, 
set, clasped and soldered to each other around the 
edges of their large bases. After filling, the hole 106 
GAS WARFARE 
is hermetically sealed by a disc of tin soldered to the 
body of the grenade. The gaine, made of special 
metal, holds the charge of explosive powder. It is 
threaded on the interior to receive the fuse plug 
which forms the body of the firing mechanism, 
which is automatic but is without a detonator. The 
fuse requires five seconds for combustion. A rub- 
ber washer placed between the upper flange of the 
gaine and the shoulder of the fuse plug, forms a 
tight joint for the grenade. The total weight of 
the charged grenade is 560 grammes or 1.23 lbs., 
and the charge is 300 grammes of white phos- 
phorus. 
Method of Use.-Hold the grenade in the throw- 
ing hand, the firing mechanism up, in such a man- 
ner as to secure the lever. Pass the index finger of 
the free hand through the ring and withdraw the 
safety pin. The grenade is now armed and the 
bomber must take every precaution not to release 
the grip on the lever until the grenade is thrown. 
The grenade when thrown, bursts into flames five 
seconds after the lever is released, producing a cloud 
of dense white smoke and suffocating vapors. The 
range of the grenade is 25 to 30 meters. Its explo- 
sion does not produce any dangerous metallic pieces 
but throws in all directions within a radius of 15 td 
20 meters pieces of burning material (W. P.) ca- 
pable of causing serious burns and which also con- 
stitute a possible source of fires. The burning of 
this material is prolonged for several minutes after 
the explosion, forming an abundance of white 
smoke. With a favorable wind, 20 grenades are 
sufficient to create an extended smoke cloud. 
Action.-Upon leaving the hand of the thrower, GAS WARFARE 
107 
the lever, which is no longer held by the safety pin, 
is projected from the grenade by the bolt. The re- 
moval of the lever permits the functioning of the 
automatic firing mechanism which sets off the 
primer. The primer ignites the slow fuse which 
after five seconds ignites the black powder charge 
in the gaine. This explodes the grenade with suf- 
ficient force to scatter the burning contents over a 
radius of 15 to 20 meters and at the same time pro- 
duces an intense and suffocating vapor within a 
radius of 5 to 6 meters. 
British "No. 27, Hand or Rifle Grenade, Mark 
I."-This grenade consists chiefly of the following 
parts : the body, the gaine, and the firing mechanism. 
The body of the grenade, cylindrical in form, is 
about 3 3/4" long and 2 1/4" in diameter. It 
is made of tinned plate and is capped on either end 
with dished tinned plate stampings somewhat 
heavier than the metal forming the body. To the 
lower cap, forming the base, is soldered a steel plate 
approximately 1/4 inch thick. This steel plate is 
tapped to receive a rod fifteen inches long and of 
the proper diameter to fit the bore of the service 
rifle. The rod is used only when the grenade is 
projected with a rifle. The rods are issued detached 
from the grenades in the ratio of 60% of the gre- 
nades. To the upper cap, forming the cover of the 
body, is soldered a spigot, externally threaded to 
hold the firing mechanism. The gaine is inserted 
through the spigot and the cover, and is soldered 
to the spigot. The primer rests on top of the spigot 
and is held in place by the striker chamber. The 
primer is crimped to the fuse, on the other end of 
which is crimped the detonator, the fuse and deto- 108 
GAS WARFARE 
nator extending into the gaine. The striker is held 
by a shear wire. Over the entire firing mechanism 
is placed a metal cover, to prevent accidental dis- 
charge, the cover being held in place by means of a 
retaining pin and ring. A small hole is provided 
in the cover cap for filling. This is sealed with a 
disc of tin. The filling charge is about 400 grammes 
of white phosphorus. 
Method of Use.-(a) As a Hand Grenade. The 
cap over the firing mechanism is removed after with- 
drawing the retaining pin. The striker is then 
struck against any solid object, as the heel of the 
boot, the butt of the gun, a rock, etc.. The shock 
shears the small restraining wire and the striker 
point fires the primer and starts the fuse burning, 
(b) As a Rifle Grenade. The stem is attached by 
screwing it into the base plate of the grenade as far 
as it will go. The protecting cap is then removed, 
exposing the striker. A blank cartridge furnished 
for this purpose is next loaded into the rifle, after 
which the grenade rod is inserted into' the muzzle 
of the rifle and pushed down as far as it will go. 
The butt of the gun is set against some solid object, 
such as the bottom of the trench, a sandbag, etc., 
and the elevation adjusted according to the range 
desired. Upon the discharge of the rifle the setback 
shears the small restraining wire, permitting the 
striker point to impinge upon the primer, thus ig- 
niting the fuse which in five seconds fires the deto- 
nator. The maximum range is obtained with the 
rifle held at 45 degrees. Shorter ranges may be had 
by either raising or lowering this elevation. Under 
favorable conditions, ranges up to 230 yards are ob- 
tained. The effect of this grenade is similar to that GAS WARFARE 
109 
of the French Grenade "Incendiare et Fumigene 
Mie. 1916, Automatique." 
U. S. "Phosphorus Hand Grenade Mark II." 
-This grenade is essentially the same as the French 
"Incendiaire et Fumigene," hand grenade. 
Smoke grenades have been primarily designed as 
infantry weapons for offensive operations both as 
incendiary and smoke producing articles. They are 
suitable for burning dugouts, blinding machine guns, 
or screening small local attacks. Due to their 
scarcity, their use in producing smoke screens is 
uneconomical. These grenades on exploding scatter 
burning phosphorus over a circle of 15-20 meters 
radius. 
Used as Rifle Grenades.-The British Grenade 
the "No. 27, Hand and Rifle Mark I," is the only 
chemical grenade which has been designed for rifle 
projection. The other smoke grenades described are 
designed for hand projection only. 
The rifle smoke grenade is most effective in brush 
or wooded country, particularly where the terrain is 
undulating, thus permitting a detachment of gren- 
adiers to crawl within range of a machine gun with- 
out exposing themselves to severe fire. Unless there 
is natural cover at the firing point rifle pits should 
be scooped out so that the grenadiers will have pro- 
tection from machine guns. 
Two or three grenadiers should keep up a con- 
tinuous fire upon the machine gun attacked. Others 
are designated to work their way into close striking 
distance from whence they can rush the gun from 
the flank, under cover of the smoke. The rifle gre- 
nade is most effective when burst ten or fifteen feet 
above the ground. 110 
GAS WARFARE 
The smoke generated by the burning phosphorus 
cuts off the machine gun from the possibility of 
direct fire. This effect may often be obtained, even 
though the strong point is out of range, if it is pos- 
sible to work into a position to the windward so that 
the smoke will drift over the point to be screened. 
If an attack is held up by hostile machine guns, 
their position might be indicated by firing single 
rifle grenades toward them, targets being thus pro- 
vided on which fire from other weapons can be 
directed. 
Two men in each squad may be trained to use 
these grenades and they should carry ten each in an 
advance. 
Used as Hand Grenades.-All of the smoke gre- 
nades can be used as hand grenades. The principal 
use of the phosphorus hand grenade is as a follow- 
up of a rifle grenade, for the maintenance at short 
range of the smoke cloud when taking a strong 
point. The smoke given off by the rifle grenades 
permits the grenadiers to advance to a point where 
the hand grenades may be used. A minor use for 
the hand smoke grenade is in "mopping up" the 
enemy dugouts, although the gas grenade is more 
effective for this purpose. 
British "Smoke Candle, Mark I. (L) Type S." 
-This smoke candle consists of the following parts: 
Case, lid, tin plate cover, striker, igniting device, 
charge, powder discs, cap and band. The case is 
made of tinned iron plate, having a welded side and 
bottom seam and four plugs to secure the lid. The 
lid is made of material of the same quality as the 
case. It is pressed to the required form and has a 
central hole and four slots around its edge. The GAS WARFARE 
111 
cover is made of tin plate. The striker is made of 
strong durable tape. Secured to this tape, by means 
of glue and two wire stitches, is a cardboard disc 
coated with match box composition in the uncovered 
side. The case is charged with smoke composition. 
Method of Operation.-Tear off the top by pull- 
ing the tape quickly upwards. Ignite the flare by 
rubbing the red disc sharply and firmly across the 
black blob on its center. This operation ignites the 
match material which in turn ignites the quick 
match, which sets fire to the fire composition for 
lighting the smoke mixture. This bums and gives 
off a smoke for three minutes. 
British "Smoke Candle Mark II. (L) Type S- 
i."-This candle consists of the following parts: 
Case, lid, projector, friction thimble, striker, and ig- 
niting arrangement. The case is made of tinned iron 
plate of the form and of dimensions regularly adopt- 
ed, and has a welded side and bottom seam. The 
lid is made of stamped tinned plate and fits tightly 
on the case. The protection and friction thimble 
is stamped from tinned plate, the projector being 
slotted to allow for the passage of the tape and 
striker arrangement. The striker is made of strong 
tape, to which is fastened by means of glue and two 
wire stitches, a cardboard disc, coated with match 
box composition. A piece of paper is secured to the 
tape on the same side as the disc in such a manner 
as to cover the striker. The case is filled with 
about 3 pounds of smoke composition in a plastic or 
semi-fluid condition. 
Method of Operation.-To fire, tear off the tape 
to expose the firing composition. Rub the tablet of 
red composition, which is attached to the underside 112 
GAS WARFARE 
of the tape, smartly across the black blob of compo- 
sition in the center of the top of the candle. This 
operation causes the match material to ignite the 
igniter which sets fire to the smoke composition. 
This burns and gives oft' smoke for five minutes. 
U. S. "Smoke Torch, Mark I."-The general 
construction and method of operation of this candle 
is entirely similar to that of the British "Smoke 
Candle Mark I (L) Type S," except that the time 
of burning is four minutes. 
As smoke producers, smoke candles have about 
one-half of the efficiency of smoke grenades, but 
they have practically no incendiary effect. They are 
portable and are designed for use by infantry in 
active operations. They are useful for blinding 
machine guns, for screening local attacks, and for 
simulating gas attacks. They may be used for con- 
cealing concentrations of guns or troops, battery 
positions or areas, or putting up a smoke barrage 
along the flank of an attack. 
An operation with these candles should be carried 
out by a squad under the direction of a competent 
gas officer who makes wind observations and de- 
cides whether the candles may be used to advantage. 
At least 500 candles should be used for even a small 
operation. The number started at the beginning 
should make a dense cloud, and this can then be 
reinforced by fresh generators as required. 
The number of smoke grenades or smoke candles 
required to form an effective screen depends upon 
all the considerations enumerated under "Smoke 
Screens." No definite rules can be laid down as to 
the exact quantities of smoke producing substances 
required to form a screen, as conditions vary greatly. GAS WARFARE 
113 
Three-inch Stokes Mortar Smoke Bombs.- 
The 3-inch Stokes mortar bomb places in the hands 
of the infantry a means of forming smoke barrages 
at greater ranges than is possible with the rifle gre- 
nade. The 3-inch and 4-inch Stokes mortar bombs 
compare approximately as follows: 
Amount of W. P. 
Maximum Range 
Smoke Bomb. 
about 2.5 lbs. 
1800 yards 
4" Smoke Bomb. 
about 7.0 lbs. 
1160 yards' 
The use of the 3-inch Stokes mortar smoke bomb 
will economize on guns if they are used wherever 
possible, as they will be used from the front line 
trenches and will have a maximum range of ap- 
proximately 1,800 yards. The fact that these smoke 
bombs will be entirely under the control of the in- 
fantry operates as an additional advantage in that 
smoke barrages will at all times be available to cover 
the retirement of daylight raiding parties. 
It will also be possible to carry the mortars forward 
together with a supply of the smoke bombs to pro- 
vide smoke screens in the large stages of an infantry 
advance. CHAPTER IX 
Persistencies of Gases, Methods of Projection, Employ- 
ment of Chemical Substances in Tactics, Phosgene, 
Chlorpicrin, Mustard Gas, Brombenzyl-Cyanide, Spe- 
cial Application of the Various Groups. 
When ground has been evacuated in consequence 
of a mustard gas bombardment, the length of time 
which must elapse before it can be occupied should 
be foretold as accurately as possible. Tremendous 
advantage may be gained by being able to estimate 
this period more accurately than can the enemy. 
The rate of evaporation of a liquid from the 
ground is increased by increased wind velocity and 
especially by increased temperature. Mustard gas 
in the woods or in calm weather, will persist much 
longer than in the open or in windy weather. It 
will last longer on cold ground than on hot ground. 
However, during a cold night, an infected area may 
perhaps be traversed with little danger, provided 
the feet are properly protected, whereas the follow- 
ing morning, after the sun has warmed the ground, 
enough vapor may be given off into the air as a re- 
sult of the increased evaporation to gas severely any 
one traversing the area. 
Moisture produces (though very slowly) the 
chemical decomposition of mustard gas so that it 
will persist for a shorter time in moist soil than in 
dry soil of equal temperature. If the mustard gas 
114 GAS WARFARE 
115 
liquid is dispersed in very fine droplets, it will dis- 
appear much more rapidly than when splashed in 
large drops upon the ground. 
The table on the following page will serve to give 
a rough idea of the persistency which may be ex- 
pected from gases as spread by shell of the usual 
types. 
The persistency of mustard gas on the ground is 
diminished by heavy rain, which washes it away, 
or by sunshine or strong wind which hastens its 
evaporation. Sunshine, on the morning after a 
bombardment, may produce a dangerous concentra- 
tion of gas, where no marked effect had been no- 
ticed during the night. The wind limits for mus- 
tard gas are from calm to 12 miles per hour; the 
lower the velocity of wind, the greater the local 
concentration of gas. Variations may be expected 
according to the principles above discussed. In the 
case especially of chlorpicrin, the air may have be- 
come safely free from the gas while the ground still 
contains enough to make it dangerous to entrench 
in it. 
Chemical substances may be projected in military 
operations as follows: (a) In form of cloud gas 
discharged from gas cylinders, (b) In steel bombs 
fired from Livens Projectors, (c) In steel bombs 
fired from 4-inch Stokes mortars. In the Amer- 
ican Expeditionary Forces the three methods men- 
tioned above were used by Gas Troops for projecting 
gas. (d) In shells of various caliber fired from 
Artillery weapons, (e) In grenades (including 
smoke grenades), thrown by hand or rifle, (f) In 
form of smoke bombs thrown by 3-inch Stokes 
mortars, (g) In form of smoke candles set off in Gas 
Persistence 
Remarks 
Name 
Class 
Symbol 
In Open 
In Woods 
Vincennite 
Vitrite.. 
Collongite 
(Phosgene) 
Non 
Persistent 
V.N. 
C. C. 
C. G. 
io minutes 
3 hours 
These gases are very volatile, they are vaporized entirely 
at the moment of explosion, forming a cloud, capable of giv- 
ing deadly effects, but which loses, more or less rapidly, its 
effectiveness by dilution and dispersion into the atmosphere. 
Aquinite. 
(Chlorpicrin) 
and (Opacite).... 
(Stannic Chloride).. 
Aquinite 
Chlorpicrin 
Martonite 
(Bromacetone) 
Moderately 
Persistent 
N. C. 
P. S. 
B. A. 
3 hours 
12 hours 
These gases, having moderately high boiling points, are 
only partially vaporized at the moment of explosion. The 
cloud formed upon explosion is generally not deadly, but it 
immediately gives penetrative lachrymatory, or irritant 
effects. The majority of the "Gas" contents of the shell is 
pulverized and projected in the form of a spray or fog which 
slowly settles on the ground and continues to give off vapors 
which prolong the action of the initial cloud. 
Yperite 
(Mustard Gas)... 
Camite 
(Brom Benzyl 
Cyanide) 
Highly 
Persistent 
H. S. 
C. A. 
3 days 
7 days 
These gases, having a very high boiling point, are but 
little vaporized at the moment of explosion. A small portion 
of the contents of the shell is atomized and gives immediate 
effect, but by far the greater part is projected on the ground 
in the form of droplets which slowly vaporize and continue 
the action of the initial cloud. 
The above figures on time of persistency are approximate only and for calm weather. Persistency is dependent to a large 
extent on temperature, wind velocity, and amount of gas liberated, especially in woods or other more or less closed places. High 
temperatures and wind velocities decrease persistency and low temperatures and wind velocities increase it. 
THE PERSISTENCY OF GASES 
116 GAS WARFARE 
117 
place. The last three forms are used by Infantry, 
(h) In form of incendiary and smoke bombs 
dropped from airplanes by the Air Service. 
Meteorological, topographical, and other pertinent 
conditions being favorable to the use of gas in a 
given tactical situation the kind of gas to be em- 
ployed in the tactical operation depends on persis- 
tency and nature of the effect of the gas, whether 
temporary, permanent or delayed. It is relatively 
unimportant to distinguish between the various phy- 
siological effects which may be included under the 
above headings. For evample, it is not of great 
consequence in planning an operation to distinguish 
between temporary casualties produced by cough- 
ing, by vomiting, or by lachrymation. It is import- 
ant to know only whether the effects will be pro- 
duced rapidly and whether they will persist for a 
long time. Moreover, it is unimportant to distin- 
guish between substances on the one hand which 
produce bad bums, and those on the other hand 
which produce lung lesions. Both can be used to 
decrease the effective strength of the enemy. 
The following table, considered in connection with 
PERSISTENCE 
NATURE OF CASUALTY PRODUCED 
Temporary 
Permanent Delayed 
Group I. Low 
Diphenyl-chlor- 
arsine. 
Phosgene- 
Chlorine 
Group II. Moderate 
Chlorpicrin 
Group III. High 
Brombenzyl cyan- 
ide and other 
lachrymators (tear 
producers). 
Mustard Gas 
the preceding table, illustrates the tactical possibili- 
ties of the substances described. 118 
GAS WARFARE 
Smoke, although used for screening purposes 
rather than for toxic effect, falls within the scope 
of Chemical Warfare, and may be considered as a 
separate group. This group includes tin tetrachlor- 
ide, silicon tetrachloride, titanium tetrachloride, and 
white phosphorus. The tetrachlorides are liquids, 
non-poisonous, but producing a dense smoke, prin- 
cipally useful in ranging. Being liquids, shells filled 
with them have the same ballistic characteristics as 
gas. White phosphorus is a solid which, upon 
bursting in air, burns with a dense white smoke. It 
is useful for smoke screens. Phosphorus burns 
make ugly wounds. 
The chemical substances described may be em- 
ployed in support of troops acting either offensively 
or defensively. Offensively they must be employed 
for ..the purpose of assisting in gaining and main- 
taining that fire superiority necessary for the in- 
fantry to advance. This may be accomplished by: 
Producing casualties among the enemy personnel 
directly employed in the delivery of fire. 
Limiting the maneuvering ability of hostile forces 
by forbidding or rendering impracticable the use by 
them of certain areas heavily gassed . 
Producing casualties among hostile reserves, 
thereby reducing the strength of a counter-attack. 
Reducing the effectiveness of hostile fire by com- 
pelling enemy personnel to wear gas masks. 
Reducing effectiveness of hostile fire by establish- 
ment of a smoke screen, thus preventing aimed fire 
and observation of effect of fire by the enemy. 
By deceiving the enemy regarding the place or 
direction of the attack. 
Reducing the effectiveness of hostile fire by lower- GAS WARFARE 
119 
ing the morale of the troops continuously exposed 
to the effects of gas. 
Gas in offensive operations may be used in prepa- 
ration for the attack or during the attack. Troops 
on the defensive may employ gas to prevent the 
enemy gaining or maintaining the fire superiority 
necessary to advance. Troops on the passive de- 
fense have a wide field of use for gas because none 
of the restrictions which exist when gas is used to 
assist troops acting offensively are imposed. When, 
however, troops are acting on the defensive awaiting 
a favorable opportunity to attack, gases must be so 
employed that they shall not interfere when an 
otherwise favorable opportunity is presented to re- 
sume the offensive. 
In a withdrawal or in a retreat the employment of 
chemical substances is especially applicable as they 
may then be freely used without fear of deleterious 
effect on our own troops. Gases may be used under 
such tactical situations to reduce casualties among 
friendly troops, by screening movements of friendly 
troops and to prevent or delay pursuit, by denying 
hostile troops the use of landmarks on which to 
guide through, causing them to advance through 
smoke clouds and thereby favoring loss of direction 
by enemy units and their mixing in the advance, 
and by causing casualties among pursuing troops by 
heavily gassing areas included in their line of ad- 
vance. 
The most effective gas against hostile personnel 
may, under a given tactical situation, be one against 
which the enemy has no or only indifferent means 
of defense, even though such a gas may be of low 
persistence or have only a temporary effect on hos- 120 
GAS WARFARE 
tile personnel. For this reason it is necessary to 
know what are the limitations of the means of de- 
fense against gas available for use by the enemy. 
Assuming the enemy means of defense are efficient 
against all available gases, the kinds of gases used 
in any tactical situation depends upon time available 
before friendly troops, under the plan of operation, 
will probably occupy the area gassed, as well as upon 
meteorological and topographical conditions and the 
persistency and effect of available gases. 
Special application of the various groups of chem- 
ical substances (phosgene, chlorpicrin, mustard gas, 
brombenzyl-cyanide) are numerous and most im- 
portant. The following observations and applica- 
tions are worthy of careful notation: 
Phosgene.-During the entire period of prepara- 
tion for an attack, as well as in the earlier stages 
of preparation, when mustard gas is being used, put 
over phosgene in sudden two-minute bursts of ar- 
tillery fire, at repeated intervals of from 8 to 12 
hours, upon strong points, concentration areas, 
woods and ravines, and upon groups of trenches 
and dugouts, to kill those whose masks are worn out 
or those who, through recklessness or carelessness, 
have removed their masks. 
On targets, distant 1900 meters or more, use ar- 
tillery to carry out the tactics outlined in paragraph 
above. Whenever possible, the area within 1900 
meters of our line should be taken care of by Gas 
Troops, using cylinders for cloud gas, when the 
wind is favorable, and projectors and 4-inch Stokes 
mortars, all of which can produce much higher gas 
concentration than artillery. 
When the wind is favorable (blowing toward the GAS WARFARE 
121 
enemy), launch against the entire front to be at- 
tacked, and for miles along the front not to be at- 
tacked, heavy phosgene gas attacks by all methods, 
including cloud gas from cylinders. If the wind is 
unfavorable, phosgene may still be used with ar- 
tillery, projectors and Stokes mortars by simply re- 
ducing the amounts put over in accordance with the 
tables of safe distances. When immediate neutrali- 
zation is required, phosgene is generally preferable 
on account of its immediate effect. 
Gas troops with Stokes mortars, projectors and 
cylinders are trained to keep up with infantry re- 
serves, whence they can be directed to the support 
of attacks of strong points, machine gun nests and 
enemy troops concentrating for counter-attacks, by 
projection of phosgene, or by projection of phos- 
phorus for smoke screens. They are also equipped 
to fire upon hostile personnel with thermite, phos- 
phorus and incendiary bombs and drums thrown 
from mortars and projectors. 
With unfavorable winds phosgene and chlorpicrin 
may be used by artillery, and by Gas Troops, em- 
ploying projectors and 4-inch Stokes mortars, which 
should direct their fire just beyond the nearest enemy 
masses so as to let the gas drift back over them. The 
amount of gas must be reduced, but not necessarily 
to the amounts given as safe under rules for firing 
of gas by artillery. Some chances must be taken 
with our own gas even to the extent of an occasional 
casualty. With the new mask, giving perfect vision, 
accidental casualties should be rare. 
Chlorpicrin is stopped by the mask much less 
readily than phosgene, and in the high concentra- 
tions attainable in projector attacks heavy casualties 122 
GAS WARFARE 
may be expected. It is moderately persistent, and 
its value in artillery shell is due to this fact and to 
its lachrymatory power. From 3 to 12 hours should 
be allowed where troops are to cross the infected 
area, depending upon whether the area is open or 
wooded. 
Mustard Gas.-The characteristics which make 
mustard gas so valuable are very little odor, absence 
of immediate effect, effectiveness in low concentra- 
tions and its persistence. The following directions 
and observations are most important: 
(a) Use for harassing fire against batteries, 
strong points, woods, cross roads and enemy con- 
centrations everywhere at all times prior to attack- 
ing. (See c. d. and e.) 
(b) As it affects eyes, lungs, body and food, and 
persists for days, it wears down the enemy morale 
and vigor by forcing constant wearing of the mask 
and the necessity of always taking other extensive 
precautions. 
(c) In the open it may be used when the weather 
is clear and warm up to 3 days before an attack. 
(d) When weather is cloudy and warm, add 
1 day to (c). 
(e) When weather is cold and especially cloudy, 
allow 4 to 7 days. 
(f ) In thick woods or brush heavily bombarded 
with mustard gas, allow 5 days in warm weather and 
7 days in cold weather before attacking through 
them, except under special conditions. 
(g) An infected area may be crossed more 
safely when the ground is cold, as during the night. 
The above intervals may be reduced if this precau- 
tion is taken. GAS WARFARE 
123 
(h) Continue neutralizing and harassing fire 
against strong points, battery positions, cross roads 
and any possible concentration points during the en- 
tire battle, in accordance with the schedules given 
in (c), (d), (e), and (f). The flanks, where no 
attack is to be made by our troops, should be kept 
smothered with mustard gas to prevent the pos- 
sibility of a flank counter-attack. 
(i) It may prove possible in the future to 
change the burst of mustard gas shell so as to dimin- 
ish the persistency, allowing earlier attack following 
its use, and producing greater concentrations. 
(j) When the enemy succeeds in halting our at- 
tack at any point, use mustard gas in accordance 
with the schedules given under (e) and (f), and in 
the intervening period up to the moment of the at- 
tack, pour in phosgene with both artillery and Gas 
Troops. When the wind is unfavorable, i.e., blow- 
ing toward our troops, merely reduce the amounts 
sent over. 
(k) Gas used as explained under (j) is a valu- 
able weapon to break up resistance in general, and 
is especially valuable for use against enemy troops 
concentrated for counter-attacks. 
(1) The use of mustard gas must be continuous 
on woods, ravines, roads, villages, railroads, and 
any other places where enemy troops can concen- 
trate or where they must move. Fields that the 
enemy may cross should be thoroughly gassed. 
(m) Used in this way, it should be very ef- 
fective in inflicting serious losses from burns, even 
if the mask fully protects. 
(n) Mustard gas can be used in the offensive 
without endangering our troops, beyond or to the 124 
GAS WARFARE 
flanks of an objective. When the objective is a 
limited one, always allow clearance of one mile as a 
safety factor in case the wind should prove adverse. 
(o) Bombardments with mustard gas are best 
carried out at night, when the atmospheric condi- 
tions are most likely to be favorable, and when, 
owing to the difficulty of seeing while wearing a re- 
spirator, the maximum amount of interference with 
movement is caused. In addition, the evacuation of 
shelled areas is most difficult at night. 
Brombenzylcyanide (lachrymator ).-This is used 
anywhere to force immediate wearing of the mask. 
It is a powerful lachrymator, and very persistent, 
but not poisonous unless one is very close to a burst- 
ing shell. It is two to three times as persistent as 
chlorpicrin. 
It is useful to save mustard gas, phosgene and 
chlorpicrin, and still harass the enemy by forcing 
him to wear masks. For this purpose it is many 
times more effective than phosgene and chlorpicrin. 
It is especially useful against active combatants, 
as few guns are necessary to produce the desired 
effect. CHAPTER X 
Use of Gas by Gas Troops, Organization of Gas Regi- 
ment, Duties of Regimental Officers, Duties of Com- 
pany Officers, Stokes Mortars and Bombs, Smoke 
Bombs, Propellants and Fuses, Livens Material, 
Cloud Gas Apparatus, General Procedure in Gas 
Operations. 
The development of the use of chemicals in mod- 
ern warfare has resulted not only in the introduction 
of new weapons and methods, but also in the em- 
ployment of gas troops. The experience gained is 
sufficient to fix the field in which such troops can 
operate most effectively and point out the general 
principles underlying the most advantageous use of 
the weapons with which they are armed. Because 
of the highly technical nature of this service, troops 
engaged in it should be specially trained and 
equipped. Because of the hard physical labor re- 
quired, the personnel should be of specially good 
physique. 
The chemicals used in warfare may be divided 
into four general classes. One class comprises 
chemicals which, when breathed or brought into 
contact with the human body, produce fatal or in- 
capacitating results. Another comprises those used 
for purposes of deception or concealment. The 
third comprises incendiary agents. The fourth 
comprises high explosives. The use of these ma- 
125 126 
GAS WARFARE 
terials has brought about the perfecting of three 
new weapons, the Stokes trench mortar, the Livens 
projector and the gas cylinder. The two former 
are used for the projection of bombs or drums con- 
taining chemicals. The projectile for Stokes trench 
mortars is usually called a bomb, while that of the 
Livens projector is usually called a drum. The 
cylinder is used exclusively for the projection of 
gas clouds. Stokes mortar bombs may contain any 
of the four classes of chemical agents, but in gen- 
eral the Livens projector is limited to agents of the 
first and fourth classes only. 
Gas troops are Army troops, usually one regiment 
per Army. Their battalions and companies are at- 
tached to Corps and Divisions as required by the 
nature of the operations contemplated. As a rule, 
a unit smaller than a company should never be at- 
tached to a Division, nor a unit smaller than a bat- 
talion to any Army Corps. Gas regiments as now 
authorized consist of six battalions of three com- 
panies each, with a total of 210 officers and 4,873 
enlisted men. Of the six battalions five are combat 
battalions and one a replacement battalion. This 
is made necessary by the technical nature of the 
work, and the necessity of replacing casualties with 
trained personnel. 
The organization of the Regimental Headquar- 
ters follows that of the Special Engineer Regiments, 
except that a lieutenant colonel is provided for each 
two battalions and an additional first lieutenant is 
authorized as assistant adjutant. The enlisted per- 
sonnel of 39 is sufficient to handle only the routine 
administration work. In order to maintain the 
necessary transportation to take care of the regi- GAS WARFARE 
127 
merit's service of supply, it is necessary to call upon 
the battalions and companies for assistance. In 
normal operations, from 200 to 250 men are re- 
quired for transportation and service of supply. 
By far the best results are obtained by directing the 
use of transportation from regimental headquarters. 
Adjutant and Personnel Officer.-These duties 
follow closely those of similar positions in a normal 
regiment. 
Chemical Adviser and Intelligence Officer 
should have: (1) An exact knowledge of the char- 
acteristics and proper use of gases in gas warfare; 
and such knowledge as will enable him to forecast 
with fair accuracy the probable importance of sug- 
gested developments. (2) An accurate knowledge of 
the varying front line conditions; of the past and 
present operations of Gas Troops, and of the plans 
and possibilities for future operations. 
The duties of this officer are, to obtain, properly 
file, and transmit information, particularly with a 
view of keeping the Gas Troops informed of the 
results obtained in Gas Warfare, and of keeping 
the technical and supply divisions informed of the 
needs of the Gas Troops. Since all intelligence 
matters concerning operations pass through the 
hands of the Chemical Adviser and Intelligence Of- 
ficer, certain other duties concerning the conduct of 
operations and reports thereon, have been added to 
the foregoing. 
The Chemical Adviser and Intelligence Officer 
should, therefore: (1) Procure, digest and file 
such scientific and technical papers and publications 
as are of possible practical value to the regiment. 
(2) Keep in touch with new developments in Of- 128 
GAS WARFARE 
fense Gas Warfare, with changes in offense gas 
weapons or material, and pass on useful information 
regarding the same. (3) Forecast all the neces- 
sary ordnance supplies for the regiment. Investi- 
gate complaints regarding the technical supplies re- 
ceived and suggest any necessary improvements. 
(4) Transfer all suggestions of value regarding 
possible improvement of weapons or methods in Gas 
Warfare to the Commanding Officer concerned or 
to the Offense Division, Headquarters, Chemical 
Warfare Service, for investigation. (5) Render 
all possible assistance (consistent with other duties) 
to the Offense Division in its investigations. (6) 
Obtain information from army regarding position 
of our advance line and keep regimental headquar- 
ters map up to date. (7) Obtain daily summaries 
of intelligence published by the army and the vari- 
ous corps and divisions with whom the regiment 
is operating. Study any intelligence regarding the 
enemy positions or activity that may prove useful in 
pending operations, and furnish same to all com- 
manding officers concerned. (8) Have the loca- 
tion of all gas battalion or company headquarters 
and dumps indicated on the regimental headquar- 
ters map. Be conversant with the various means 
available for inter-communication between all regi- 
mental units. (9) Have on hand a list showing 
the location of all corps and division headquarters 
on the front where the regiment is operating and 
have same plotted on the regimental headquarters 
map. (10) Have suitable road maps of the ad- 
vance zone, showing first class "up" and "down" 
traffic routes; also have traffic maps of lines of com- 
munication. (11) Procure and keep on hand a suf- GAS WARFARE 
129 
ficient supply of suitable maps for all present and 
pending operations, and be prepared to make at short 
notice maps concerning any projects on hand. (12) 
Have on hand a relief map of the front on which 
the regiment is operating. (13) Obtain informa- 
tion as to present plans of battalion and company 
commanders and be prepared to suggest new opera- 
tions on which those units can be profitably em- 
ployed. (14) Take charge of all secret corres- 
pondence "inward" and "outward," regarding the 
employment of the regiment and its movements or 
future operations. (15) Receive all daily progress 
and operation reports from battalions and com- 
panies, check same, and be conversant at all times 
with their contents. (16) Collect and pass on to 
officers concerned intelligence on results of opera- 
tions by the regiment and the gas troops. (17) 
Compile and distribute a regimental daily bulletin 
containing information of importance or interest. 
(18) Be thoroughly conversant with all Gas De- 
fense measures, and be able to advise concerning 
any special precautions necessary to be taken by Gas 
Troops for protecting them against their own gas. 
(19) Advise the Regimental Supply Officer as to 
the location of important forward Gas Dumps and 
the storage of material in them. (20) Obtain and 
supply to all officers concerned such meteorological 
data as may be of service. 
Regimental Supply Officer.-The duties of this 
officer are as follows: (a) To anticipate the sup- 
plies required by the Regiment and deliver them 
to mobile dumps easily accessible to the companies 
and battalions. These mobile points should move 
as the units move so that the amount of truck trans- 130 
GAS WARFARE 
portation is minimized, (b) To control all motor 
and animal transportation. 
In connection with motor transportation, the Reg- 
imental Supply Officer is to maintain a suitable and 
sufficient personnel to operate and maintain all 
trucks, touring cars and side-cars assigned to the 
organizations. 
The Regimental Supply Officer cares for the re- 
placement of all animals injured or taken sick, rec- 
ommends personnel to handle them and arranges 
for periodic inspection as a check on their care, use 
and proper shoeing. He also assists the companies 
and battalions in arranging for any rail shipment 
they may be required to make, and takes care of 
any construction work and any other miscellaneous 
work which obviously is not a part of the duties 
of the other staff officers. He works with the Bat- 
talion Supply Officers, and through them with the 
Company Supply Officers, and sees that each is ac- 
quainted with and performs his full duty. 
Master Engineers.-The duties of the Master 
Engineers are as follows: 
Chemical Assistant.-This assistant operates 
directly under the orders of the Regimental Chemi- 
cal Adviser and Intelligence Officer and assists him 
in every way in chemical matters. 
Map and Intelligence Assistant.-This assist- 
ant is charged, under the Regimental Chemical Ad- 
viser and Intelligence Officer, with maintaining com- 
plete map files and all intelligence covering opera- 
tions. 
Training Assistant.-This assistant is charged, 
under the Regimental Chemical Adviser and Intelli- GAS WARFARE 
131 
gence Officer, with the coordinating and assisting 
in the training and instruction. 
Transportation Assistant.-This assistant is 
charged, under the Regimental Supply Officer, with 
looking after the work in the transportation division 
and includes operation and maintenance of all motor 
vehicles. 
Supply Assistant.-This assistant functions di- 
rectly under the Regimental Supply Officer. 
Special Equipment Assistant.-This assistant 
is charged, under the Regimental Supply Officer, 
with keeping fully informed on Special Equipment 
situation as regards manufacture, supply in all de- 
pots, and supply of troops operating on the lines. 
Construction Assistant.-This assistant func- 
tions directly under the Regimental Supply Officer 
and is available for all construction work. He must 
be a man capable of handling men on general con- 
struction work. 
Military Assistant.-This assistant functions un- 
der the Regimental Adjutant. He is available for 
the training of replacements, for taking charge of 
or assisting in special technical training. 
The duties of the Battalion Staff Officers, while 
following generally those of similar positions in the 
normal battalion, also parallel to a great extent the 
duties of the corresponding regimental positions 
outlined above. The duties of Battalion Staff Of- 
ficers are, furthermore, made difficult by the neces- 
sity of controlling and supplying units operating 
over an extended front and in small detachments. 
The company is organized into a headquarters 
section and four platoons. The headquarters sec- GAS WARFARE 
132 
tion takes care of the normal administration of the 
company, thus leaving the platoons free for actual 
fighting. Each platoon is organized into two sec- 
tions and each section consists of two Stokes mortar 
gun-teams with a carrying party. This gives six- 
teen mortars per company. All platoons are trained 
in projector and cylinder work. 
The platoon is the working unit of the regiment. 
This is specially true in a war of movement. It is 
rarely necessary to install more than four guns in 
conjunction with the advances or attacks of an in- 
fantry regiment, and when it is necessary for one 
company to operate on a divisional front, such an 
arrangement permits covering the front not only at 
the start of the operation but also enables the pla- 
toons to follow the infantry regiments to which they 
are attached and give assistance as the attack de- 
velops. 
Each platoon is organized as an independent unit 
insofar as concerns its independent functioning in 
action. This calls for the assignment of a cook and 
the supply of the necessary cooking equipment. 
Each company should be supplied with four small 
field ranges in addition to the regular rolling kitchen. 
The commissioned personnel of the company con- 
sists of nine officers, two of whom are captains. 
The additional commissioned personnel is made 
necessary by the character of the work and the en- 
tire number is necessary to insure proper func- 
tioning. 
It is impossible for one officer to properly com- 
mand the company, care for his men and at the 
same time carry on the extensive liaison that is 
necessary in the functioning of a gas company. The GAS WARFARE 
133 
addition of the second captain (the Second in Com- 
mand), fills a need and has proved to be a necessity 
in action. 
The Company Commander (i) actually com- 
mands the company and carries the full responsi- 
bility of the position. (2) He directs and supervises 
the training of his company. (3) He per- 
sonally directs disciplinary actions and is respon- 
sible for the discipline of the company. (4) It is 
his duty to see that all officers under his command 
have the requisite technical knowledge and training. 
(5) It is his duty to see that all officers perform 
their full duty and actually accept the full respon- 
sibilities of their respective duties. (6) He per- 
sonally examines, verifies and signs all reports and 
letters connected with the company work. (7) He 
makes inspections from time to time to ascertain 
whether the company is properly clothed and 
equipped and whether the equipment is up to the 
standard set. (8) He designates the approximate 
location of advanced company and platoon head- 
quarters and dumps. (9) He makes the necessary 
forecasts covering amounts and kinds of ammuni- 
tion and supplies needed. (10) He issues the 
necessary orders to cover reconnaissances and oper- 
ations. (11) He carries on and maintains liaison 
with Division and Brigade Headquarters. (12) He 
keeps fully informed of the tactical situation, the 
plans of the various Commanders and makes the 
necessary recommendations covering the correct 
and best tactical use of the Company. (13) He as- 
sists the Platoon and Section Leaders in perfecting 
and maintaining liaison with Regimental and Bat- 
talion Headquarters. (14) He obtains informa- 134 
GAS WARFARE 
tion as to enemy troop concentrations and sends 
data to Platoon Leaders as to possible targets. (15) 
He arranges necessary system of runners and neces- 
sary passage of messages between the units of his 
command and units with which he may be oper- 
ating. 
The Second in Command (1) keeps himself pre- 
pared to take up the duties and responsibilities of 
the Company Commander at any time. (2) He 
sees that all orders and instructions are complied 
with and routine matters carried out. (3) He su- 
pervises the care of the men, their training and 
equipment, and is responsible for the company at 
all times ready for immediate service. (4) He car- 
ries on the interior administration of the company. 
(5) He establishes and arranges forward company 
billets and dumps and sees that necessary and proper 
guards are established. (6) He must see that 
proper messing arrangements are made and that at 
all times the men are supplied with proper food. (7) 
He personally checks up the ration issue and sees 
that rations are properly used. (8) He supervises 
the supply of munitions as given by forecasts of 
the Company Commander. (9) He keeps himself 
fully informed of the existing tactical situation of 
all company units. (10) He is the Company Gas 
Officer and is responsible for the gas discipline of 
the company. 
The Company Supply Officer is responsible for 
supplies, transportation and records. All supplies 
(quartermaster, ordnance, signal, engineer, techni- 
cal supplies and rations) must be requisitioned 
through the Battalion Supply Officer. When the 
company is operating independently, rations are GAS WARFARE 
135 
drawn from the units to which the company is at- 
tached. Each corporal is held personally responsible 
for the condition of his men's equipment and must 
report once each week to his platoon commander 
who reports to the Company Supply Officer. Com- 
pany Supply Officers make a weekly report to the 
Battalion Supply Officer, showing their exact pres- 
ent needs and their immediate future needs. 
The minimum amount of transportation required 
to perform the operation in hand and amount of 
time required must be estimated. Particular atten- 
tion should be paid to the type of transportation best 
adapted to the operation; e. g., rail, truck, animal or 
narrow gauge. This information should be con- 
veyed to the Battalion Supply Officer requesting that 
he furnish the transportation. Careful written or- 
ders with map should be given the non-commis- 
sioned officer in charge of the transportation. These 
should state the time the transportation is to leave, 
the cargo to be carried, the route to be followed, 
the destination, and to whom the material is to be 
delivered. The non-commissioned officer acting as 
convoy must check the list of material delivered and 
report the same to the Company Supply Officer, and 
he in turn to the Company Commander. All com- 
pany transportation is under his immediate control 
as regards operation. The Company Supply Officer 
must know at all times the location of all trucks as- 
signed to his company, their condition, and the work 
upon which they are engaged. All unserviceable 
trucks must be reported immediately to the Regi- 
mental Headquarters for disposition. Transporta- 
tion is not to be overhauled by the companies. 
Careful records must be kept by the Company 136 
GAS WARFARE 
Supply Officer showing the disposition of all ma- 
terial and equipment issued to his company. These 
records should be kept so that at any time he can 
render a report showing the amount of loss of any 
particular supplies by his company. 
The Platoon Leader (i) must fight his platoon 
along correct tactical lines. (2) He must person- 
ally see that his platoon is properly clothed, 
equipped, fed and housed. (3) He must carry on 
and maintain proper liaison with company and units 
to which attached. (4) He must make necessary 
local reconnaissances and select suitable emplace- 
ments with maximum possible protection. (5) He 
must actually direct the work of his platoon and 
personally check up the construction of the emplace- 
ment, sighting and elevations of guns, make neces- 
sary examination of guns and ammunition and all 
other matters pertaining to the operation. (6) He 
must know each man in his platoon by name and 
make a study of his abilities. (7) He makes out 
accurately, necessary reports and forwards them to 
the Company Commander. (8) He must keep his 
platoon prepared for service at any time. (9) He 
must personally take charge of the men's technical 
training under the supervision of the Company 
Commander and Second in Command. (10) He 
takes charge of his platoon at all company forma- 
tions and drills. (11) He, from all his personal 
knowledge of his men, advises the Company Com- 
mander as to the qualifications and shortcomings of 
his men and also recommends promotions. (12) 
He personally sees that all orders pertaining to his 
platoon are carried out. 
Four-inch Stokes Material.-The 4-inch Stokes GAS WARFARE 
137 
mortar is, within its range, a particularly suitable 
weapon for gas projectiles, owing to its comparative 
accuracy and rapid rate of fire, and to the quantity 
of gas which each bomb contains (about 2 1/2 
quarts). The comparative silence and absence of 
flash on discharge are useful when surprise is de- 
sired, and very heavy concentrations of gas can be 
established at the target in a short period of time. 
This mortar is quickly placed in position. It can 
be used for several purposes and it is sufficiently 
mobile to be carried forward with infantry for em- 
ployment from advanced positions. It consists of 
a steel barrel connected by a double collar to a tubu- 
lar steel stand which is fitted with elevating and 
traversing gears. The breech piece of the mortar 
rests on a base plate with socket. The mounting 
admits of the mortar being traversed 2 1/20, tra- 
versing to the right or left of the central line with- 
out moving the legs of the stand or the base plate. 
The rate of fire by day for a short period is 20 
rounds per minute, although with a well trained 
detachment a higher rate can be obtained for short 
bursts, not exceeding one or two minutes. At night 
12 rounds per minute is all that can be expected. 
Barrel.-This consists of a solid, drawn steel 
tube, 48" long, with a smooth bore varying from 
4.15" to 4.20" in diameter. Two bands are clamped 
around the barrel near the muzzle to engage the 
bipod carrying the elevating and traversing devices. 
In the base of the barrel is screwed a breech piece 
containing a striker stud or anvil. This anvil has 
a flat top for firing cartridges and a nipple for firing 
biscuits. 
Stand or Bipod.-This is the gun supi>ort and 138 
GAS WARFARE 
carries the elevating and traversing mechanism. It 
consists of two tubular steel legs with a cross stay 
and spiked feet to prevent spreading. 
Base Plate.-This is an octagonal steel plate with 
a flanged socket for the reception of the breech 
piece. The American base plate is similar to the 
British except that it is round instead of octagonal. 
Base plates are usually reinforced with heavy oak 
planking to prevent their displacement when firing. 
The weights of the various parts of the mortar 
are as follows: 
Stand 30 lbs. 
Barrel 90 lbs. 
Base Plate 60 lbs. 
Wood sub-base 60 lbs. 
The mortars above described are of British man- 
ufacture. American mortars are practically identi- 
cal except for some slight difference of weights. 
Stokes Mortar Bombs, as used by Gas Troops, 
are of four types, gas, thermit, smoke, and ranging. 
All American bombs are made of wrought iron or 
steel. All bomb bodies are painted dirty white, and 
when filled have a red band near the top of the body. 
Two bombs are packed in a box, complete with 
charges and fuses. The boxes measure approxi- 
mately 2 feet 2 inches by 7 1/2 inches by 11 1/2 
inches. 
Light Smoke Bomb.-This is a 16-pound bomb 
consisting essentially of a steel cartridge container, 
sheet metal body, and a canister containing red phos- 
phorus. The canister is kept in position and the 
whole bomb cemented together by a layer of pitch. GAS WARFARE 
139 
The gaine consists of a .410 cap, a length of Bick- 
ford fuse, and a primer which explodes an ophorite 
charge in the bottom part of the gaine. The cap 
is fired by a spring striker head, so adjusted that 
the inertia of the striker is sufficient to compress the 
spring and fire the cap on discharge. This bomb 
is fired with a ballistite cartridge which gives a 
maximum range of 460 yards. For this reason the 
bomb is seldom used except for training purposes. 
Heavy Smoke Bomb.-This is a 25-pound steel 
bomb, of general construction, and contains 71/4 
pounds of white phosphorus. It is fired by the 
British 31-D or 79 fuse. 
Incendiary Bomb.-This is similar to the heavy 
smoke bomb in general construction and takes the 
same fuses. It weighs 22 pounds and contains 7 
pounds of thermit. 
Gas Bomb.-There are over fifty different kinds 
of British gas bombs, different in details of con- 
struction and operation. But they may be divided 
into two general types-old style, fired with E. C. 
biscuits; and new style, fired with cordite rings and 
with either pink or blue cartridges. 
Ranging Bomb.-This is a bomb partly filled 
with black powder, to be used for ranging or regis- 
tering purposes. It may be fitted with either the 
cartridge container for firing by cordite rings, or 
with the biscuit container for firing with biscuits. 
It is little used except for instruction and practice. 
American Stokes Bombs.-American bombs 
have been standardized, differing only in the gaine 
tube. They all use the same propelling charge and 
fuse. This will give all bombs uniform range. 140 
GAS WARFARE 
There are three general types of propellants used 
with the present British Stpkes mortar ammuni- 
tion-E. C. 3 powder, cordite, and ballistite. 
British E.'C. 3 Powder.-This propellant is used 
with all British gas ammunition and ranging bombs 
furnished gas troops. It is usually made up in the 
form of biscuits containing 400 grains of E. C. 3 
powder each. One, two or three biscuits may be 
used, being placed in what is called the biscuit con- 
tainer which is screwed onto the base of the bomb. 
When less than three biscuits are used the extra 
space in the container is filled with felt wads. The 
biscuits are fired by a .303 cap reinforced with pow- 
der and protected from damp by a disc and varnish. 
Caps should be examined before firing. If they fit 
loosely in the container they should be removed and 
new ones substituted, as loose caps often cause 
misfire. 
British Cordite Charges.-This ammunition is 
used with all thermit and heavy smoke bombs. It 
consists of a 12-gauge cartridge containing 150 
grains of cordite, or ballistite and from one to four 
rings of 350 grains each. In firing the cordite cart- 
ridge is placed in a cartridge container screwed on 
the base of the bomb, and 1 to 4 rings placed around 
the cartridge container, depending upon the range 
desired. The cartridges bear their own strikers, 
which are protected by a ring. Blunt strikes or 
anvils turned down to a smaller diameter than the 
protective ring, are used for firing. The objection 
to this charge is that it makes a very strong flash 
and soon dirties the mortar. 
Recent ammunition has been furnished with a 
blue cartridge containing 95 grams of ballistite in GAS WARFARE 
141 
lieu of the cordite (called pink cartridge) described 
above. This substitution has been made to reduce 
the flash of discharge, but has also reduced the range 
by approximately 10%. 
British Ballistite Charge.-The ballistite charge 
consists of a cartridge containing 350 grains of bal- 
listite primed with gun cotton. It is used only with a 
light smoke bomb. It is fired by means of a striker 
clip and a flat anvil similar to that used for the 
cordite cartridge. 
British Mills Pistol Head.-This is used for 
firing all gas bombs. On discharge, the inertia pellet 
depresses its spring, releasing the lever, which in 
turn releases the striker pin. The striker spring 
being under compression expands and impinges the 
striker pin against the detonating cap in the end of 
the gaine tube. This fuse does not operate unless 
the bomb has sufficient velocity to travel 100 yards. 
British Allways or 146 Fuse.-This is a percus- 
sion fuse which has also been used with gas bombs. 
An instantaneous fuse must be used in place of the 
ordinary time fuse in the bomb. Upon firing, the 
tape retaining pin is dislodged, allowing the tape 
to unwind during flight. This action causes the 
safety bolt to drop out, arming the fuse. Upon im- 
pact the steel ball forces down the striker holder, 
forcing the detonator and igniting the instantaneous 
fuse. Immediately before firing, the safety pin arm 
must be withdrawn. On no account should the tape 
be disturbed. If on withdrawing the safety pin, the 
tape retaining pin is released, it must be replaced 
before firing. 
31-D Fuse.-This fuse was formerly used on all 
thermit heavy smoke and ranging bombs. It was GAS WARFARE 
142 
only an improvised fuse, made by modifying- the 
obsolete No. 31 British artillery fuse, and it is now 
being supplanted by the No. 79 (Sutton) Mark II 
fuse. The 30-D fuse consists of two powder trains, 
set by means of a time scale. On discharge, the 
set-back pellet fires the cap, which ignites the powder 
train. This in turn ignites the powder charge which 
explodes the bursting charge in the bomb. 
British Sutton or 79 Fuse.-This fuse is used 
on all thermit, heavy smoke and ranging bombs. 
To set the fuse, the indicator mark in line with the 
auger hole is turned to the graduation required, and 
the time train in the base of the fuse punctured by 
means of an auger. The safety pin should not be 
withdrawn until the moment of firing. This should 
be done with care, as a fuse cannot be clamped, and 
any alteration in the setting will cause blinds. On 
discharge, the set-back pellet fires an explosive cap, 
which in turn ignites the powder train, and thence 
the powder in the chamber. 
American Trench Mortar Fuse Mark V.- 
This fuse is a simple time fuse for all 4" trench 
mortar bombs where air bursts are desired. It is 
essentially a copy of the British No. 79, Mark II. 
American Trench Mortar Fuse, Mark XI.- 
This is an "Allways" percussion fuse and is to be 
used on all American 4" trench mortar bombs for 
contact bursts. The safety pin is withdrawn just 
before firing. On shock of discharge, the pellet sets 
back, allowing the safety fork to fly out, thus arm- 
ing the fuse. On impact, the striker fires the cap, 
igniting the powder charge and thus exploding the 
bursting charge in the bomb. 
The Livens Projector is a very simple form of GAS WARFARE 
143 
mortar which projects quantities of gas, incendiary, 
or high explosive substances, by means of cylindri- 
cal drums rounded at both ends. This projector is 
a smooth-bore steel tube closed and rounded at one 
end and open at the other, having an internal dia- 
meter of 8". Projectors are made in various 
lengths. The several types of the Livens Projectors 
are as follows: 
Mark No. 1. 
Length 2'9" 
Thickness 3/8" 
Weight 105 lbs. 
Material Solid drawn steel. 
Length 2'6" 
Thickness 1/4" 
Weight 65 lbs. 
Material Lap welded mild steel. 
Length 4'6" 
Thickness 3/8" 
Weight 150 lbs. 
Material Solid drawn steel. 
Mark No. 3. 
Mark No. 9. 
American Projectors.-The American projec- 
tors are copied from the British. They are made 
in two sizes, Mark I (barrel length 2'9", weight 
approximately 100 pounds), and Mark II (barrel 
length 4', weight 150 pounds). All projectors have 
an internal diameter of 8". The wire wrapping of 
projectors gives greater strength for euqal weight 
and thus allows for a greater chamber pressure; 
hence, a larger propellant charge may be used, there- 
by insuring greater range. Increased portability 
can also be obtained without decrease of range. 
The Livens projector base plate is of pressed steel 
about 1/4" thick and 18" in diameter. It weighs 
about 30 pounds. It is used as a backing to pre- GAS WARFARE 
144 
vent the projector from burying itself in the ground 
on recoil. There is also a 12" base plate, the only 
difference being that the crimped edges are flat- 
tened instead of slanting as in the 18". 
The Livens Drums are of three classes, gas, 
incendiary and the high explosive. All drums are 
made of mild steel pipe with ends nosed or spun 
in. They are 21" in length and have an outside 
diameter of 7-11/16". There is a central tube run- 
ning the length of the drum welded in to the drum 
at both ends. 
In the latest designs of the gas drum the in- 
ternal diameter of this tube is slightly more than 
1". These drums are filled through holes bored in 
this tube about 2" from the end opposite the fuse 
socket. Below these filling holes the central tube 
is sealed by a steel plug welded in place. After fill- 
ing, the drum is sealed by screwing a taper plug in 
the filling end. The incendiary drum is similar to 
the gas, the only difference being in the size of the 
central tube and the method of filling. This drum 
is filled from the ouside through a hole about 2" 
in diameter, cut in the shoulder of the drum at the 
fuse end, and closed by a screwed plug. The high 
explosive drum is the same as the incendiary in 
construction. 
Gaine Tube.-This is a copper tube containing 
the bursting charge of the drum. In the gas drum 
this tube is about 17" long and .875" wide, while 
in the incendiary its length is 19.3" and width 1.12". 
The bursting charge consists of 60 grams (about 
2 ounces) of T.N.T. for the gas drum, and 2 ounces 
of ophorite for the incendiary. 
The priming system used in all Livens drums GAS WARFARE 
145 
consists of a .410 pistol cap; a 22 second Bickford 
time fuse, 10" in length; and a No. 8 commercial 
detonator loaded with fulminate of mercury to de- 
tonate the bursting charge. The detonator is at- 
tached to one end of the Bickford and the pistol cap 
to the other; the whole is then inserted in a thin 
brass casing which in turn is placed in the gaine 
tube. The pistol cap is fired by means of a device 
known as a Livens or Mills fuse. The time of burn- 
ing of this fuse may be varied by cutting off part 
of the Bickford and crimping on a new detonator 
at the desired length. This practice is not satisfac- 
tory for the reason that in the field it is difficult to 
make a moisture-proof joint between the detonator 
and the Bickford fuse. An "Allways" time and 
percussion fuse has been developed in the United 
States for the several types of Livens drums. 
Propelling charges are contained in a cylindrical 
tin box divided into one central compartment and 
six radial compartments. One compartment con- 
tains 12 ounces of cordite, inserted into which is an 
electric fuse and 4 ounces of black powder a priming 
charge. The charge is made up of small bags con- 
taining various amounts of U. S. smokeless powder. 
Range variations are obtained by varying the 
amount of powder in the charge box. The top of 
the tin container is a stamped steel plate 11/64" 
thick. The flanges of this plate overlap the sides 
of the charge box. On discharge this plate is forced 
out against the sides of the projector and serves 
as a gas check. 
Electric Fuses.-The British electric fuse used 
to ignite the cordite propelling charges is known as 
the Mark III, No. 14. In this fuse a fine platinum GAS WARFARE 
146 
iridium wire extends between two copper terminals, 
projecting from a hard rubber casing. Around this 
wire is wound a small piece of guncotton, and a 
charge of 2.25 grams of black powder which is 
set off by the guncotton, and in turn explodes the 
black powder in the bag surrounding the fuse and 
hence the cordite propelling charge. The wire has 
a resistance when cold of 1.06 ohms, and 2.6 ohms 
on fusion. A current of 0.9 amperes is required 
to fuse the wire and this amount must be supplied 
in order to be certain of setting off the guncotton. 
The American electric primer is a copy of the Brit- 
ish No. 14 fuse. 
Exploder.-What is known as an exploder for 
Livens projectors is a small plunger driven, series 
wound dynamo. The Mark V is the one now used. 
It should fire a fuse through 100 to 130 ohms re- 
sistance. Before being taken up to the front for 
use, the exploder should always be tested to find the 
actual resistance through which it fires. This is 
done by connecting it up in series with a resistance 
box and a 1 /4" gap, across which a bridge of plati- 
num iridium wire of the same nature and dimen- 
sions as that in an electric fuse is placed. The 
tested resistance should equal the sum of the re- 
sistance of the main leads, the leads between the 
guns, and the fuses, plus an allowance for resist- 
ance of joints, inequality of fuses and safety. This 
"factor of safety" is taken 25-33%. Mark1 V 
should never be used to fire more than 20 guns. 
The fuses used with the Livens drums are of two 
types, both being time fuses. The Mills pistol head 
is the same as that used on the Stokes gas bomb. 
On discharge the inertia pellet is forced back, re- GAS WARFARE 
147 
leasing the lever, which in turn releases the striker, 
and detonates the cap in the gaine. 
The Livens head is the fuse now commonly used. 
It consists of a small inertia pellet, held in place by 
a thin wire. On discharge the inertia pellet is forced 
back, shearing the wire and detonating the cap. 
The object of the shear wire is to prevent accidents 
from shorts. If the velocity of discharge is below 
a certain value, the wire does not shear and the cap 
is not detonated. 
Whenever installing the projectors a "V" shaped 
trench is dug about 3'6" wide, 1'9" deep, and 30' 
long, perpendicular to the line of fire. The pro- 
jectors are set at an angle of elevation of 45 degrees 
by means of a clinometer, and aligned by means of 
a compass. It is generally not necessary to set each 
gun separately. If one gun is carefully set, several 
may be aligned from it, with sufficient accuracy. 
Projectors are generally dug in, in batteries of 20 
each; the various batteries of an emplacement being 
scattered as the conditions of terrain and cover ne- 
cessitate. 
Early in the European war cylinders containing 
about seventy (70) pounds of liquefied gas were 
used by both sides for cloud gas, or gas wave at- 
tacks. The cylinder used was about 3'9" in height 
and 8 1/2" in diameter, similar in all respects to 
the common Co2 cylinder. The siphon tube, about 
3/4" in diameter, extended from a valve at the 
top of the cylinder nearly to the bottom. The pres- 
sure of the gas forced the liquid up this siphon tube 
through the valve and out into the atmosphere 
through a parapet pipe, where it vaporized. 
The cylinders were placed far forward in the 148 
GAS WARFARE 
trench system, usually in sets of fours, connected by 
rubber hose to a four-way connection and single 
parapet pipe. At first, cylinders were used in about 
the ratio of i per meter of front on which the at- 
tack took place. More recently 3 per two meters, 
or even 2 per meter were used. This was accom- 
plished where the width of the trench permitted 
of double banking. The cylinders weighed, when 
full, about 140 pounds each. 
After a close study of the tactical situation, 
enemy concentrations, the terrain, and time allowed, 
the Company Commander decides upon his plan of 
observations. He then prepares a project which he 
submits to the Chief of Staff of the division. The 
project generally covers the following points: (1) 
Map reference. (2) Object of proposed opera- 
tion. (3) Emplacements and target. (4) Loca- 
tion of billets desired. (5) Assistance or material 
needed from Division (transport, carrying parties, 
etc.). (6) Safety precautions to be taken by units 
holding line. (7) Wind limits, with map, and 
(8) Estimate of time required for installation. 
On approval of his project the company com- 
mander gives detailed instructions to his platoon 
commanders, assigning them definite duties. These 
instructions should be given in conference, and con- 
firmed in writing. 
All gas officers commanding units assigned to 
support infantry units will immediately report to 
the commanding officer of such infantry unit, pre- 
pared to submit recommendations regarding the 
employment of their gas troops. After reporting to 
the infantry commander each comes directly under 
his orders and is directly responsible to him for the GAS WARFARE 
149 
proper conduct of his command, in accordance with 
the orders issued by such infantry commander. Un- 
til he is relieved by the latter he is subject only to 
his orders, superior commanding officers of gas 
troops having no authority to issue orders to him 
affecting the employment of his troops. 
Commanding officers of all gas troops in assign- 
ing units under competent orders, to operate with 
infantry units, carefully instruct the commanders of 
such units, in order that they shall fully understand 
from whom they receive and obey orders and that 
they are not sent into combat to conduct independ- 
ent operations. 
Platoon leaders make their own detailed arrange- 
ments, and assign the tasks in their own platoons. 
They organize their platoons as required for carry- 
ing, digging in, and camouflaging. Their orders 
specify the approximate emplacements and target. 
They must in general determine range, changes, and 
angle of fire. Their plan of operations, with de- 
tailed instructions, should be written and submitted 
to the company commander for check and approval. 
As soon as material arrives, the installation is 
commenced. As a rule all work must be done at 
night, in absolute darkness, and silently. This 
means that each man must know his task, and carry 
it out promptly and carefully. All material sent 
forward must be complete and ready for use. No 
necessary item must be omitted. 
Work done by gas troops in forward areas must 
be directed and controlled with the greatest care 
and caution. The enemy must not be forewarned 
by sound or sign. The success of the entire opera- 
tion depends primarily upon surprise. Warning to 150 
GAS WARFARE 
the enemy will result in a heavy shelling of the 
area, and probably in a withdrawal of the target. 
Camouflage is the concealing of all work done 
in such a manner as to give no sign of activity or 
change. It must, therefore, conform to the sur- 
roundings. It must protect against: (i) Aerial 
photography, (2) air observation-airplane or bal- 
loon, (3) direct observation. It is necessary to con- 
sider and provide against new tracks, regularity of 
lines, production of shadows, and leaving any work 
uncovered. 
Preliminary reconnaissance must include a special 
study of camouflage requirements, and the report 
cover the exact kind and amount needed. Natural 
camouflage is superior if it can be obtained without 
being itself noticed. The concealment of emplace- 
ments must be carefully supervised each morning 
before leaving. In difficult cases the division cam- 
ouflage expert may be called on for assistance. 
When the installation is nearly completed, the 
Company Commander issues his operation order. 
In addition, a company operation order is issued 
giving the duties of all platoon or section leaders in 
the operation. 
The zero hour is usually set in conference with 
the Chief of Staff of the Division, as it may be de- 
pendent on other operations. If not, the best time 
to shoot is at night, when the target is most heavily 
held, or in general when the chances of surprise are 
greatest. 
Liaison.-Experience has demonstrated the great 
importance of good liaison. It must always be 
maintained with all units whose operations are in 
any way dependent upon or influenced by the opera- GAS WARFARE 
151 
tions of the gas troops. In normal operations tele- 
phones, runners or dispatch riders may be utilized. 
Use of telephones is not advisable since unusual 
activity is apt to arouse suspicion. Dispatch riders 
are not reliable. A good runner system is therefore 
essential. In planning operations, runners must be 
provided for, and trained. They are always sent in 
pairs, and should be sent frequently over their 
routes, both by day and night, to insure proper liai- 
son in action. 
From company headquarters to the rear the army 
dispatch service should normally be used. All mes- 
sages should be properly addressed and marked "to 
be called for." Messages for Regimental Head- 
quarters of Gas Troops will normally be sent "in 
care of Army Message Center," for Battalion Head- 
quarters "in care of Corps Message Center." 
In active operations where platoons may be de- 
tached from company headquarters, it may be inad- 
visable to utilize company runners, in which case 
messages may be sent to company "in care of Divi- 
sion Message Center." 
Since both Stokes mortars and Livens projectors 
are more or less crude forms of artillery, they have 
large dispersions of shots, both in range and deflec- 
tion. Moreover, due to defective propellants, etc., 
shorts quite frequently occur. These short shots 
may fall only one or two hundred yards from the 
emplacement and if the fuse is armed they explode 
and become a source of danger to our own troops. 
It therefore becomes necessary in conducting Stokes 
and Livens projector operations to prescribe certain 
safety zones for our own personnel and to remove 
all troops from territory outside the safety limits. CHAPTER XI 
Tactical Use of Gas, Thermit and Smoke by Gas Troops, 
Choice of Weapons, Training of Gas Troops, Liaison, 
Service of Security and Information, Training of 
Special Detachments. 
The amount and the kind of gas used by gas 
troops should conform to tactical conditions, having 
due regard for wind and terrain conditions. 
In an Active Offensive.-Gas may be correctly 
used as follows: (a) Preceding an attack, all en- 
emy targets should be kept under a gas atmosphere, 
allowing only a reasonable time for clearance be- 
fore the arrival of our troops. Only by so doing 
can the full benefit be derived in producing casual- 
ties, demoralization, reduction in fighting efficiency, 
and morale, (b) During a temporary check of an 
advance, extending from a few hours to several 
days, gas should be used on enemy concentrations, 
villages, strong points, woods, reverse slopes and 
machine-gun nests, (c) During organization and 
consolidation of the line gas should be used as for 
a temporary check, with special attention to sectors 
from which counterattacks may be launched, (d) 
During nights of an advance gas should be used on 
enemy supports and reserves, and on machine-gun 
nests and strong points, (e) Against machine-guns 
just before an attack, a judicious use of gas by 
Stokes mortars is an effective means of handling 
152 GAS WARFARE 
153 
this form of defense. Placing from two to ten 
bombs of phosgene, depending on wind and terrain 
conditions, in a machine-gun nest establishes a local 
concentration sufficient to kill and force enemy to 
wear masks or abandon guns. The gas will have 
dissipated sufficiently by the time of arrival of our 
own troops to be safe. Close cooperation between 
the advanced infantry units and gas troops will al- 
low this result. Troops must become accustomed 
to the smell of slight concentrations of phosgene, 
and should be taught to advance through or around 
it, just as they are trained to follow a barrage. 
In Stabilized Warfare.-Surprise shoots of high 
concentration may be used on enemy concentra- 
tions, machine-gun and minenwerfer emplacements, 
strong points, trench intersections, and from one 
end of the line to the other, when conditions are 
favorable. 
Thermit may be used under conditions similar to 
the above, when conditions of wind or terrain pre- 
vent the use of gas. 
The intelligent use of smoke in modern infantry 
tactics offers many advantages arising from con- 
cealment and deception. It may be correctly used 
by gas troops as follows: (a) To mask enemy 
observation posts and blind hostile machine-guns, 
(b) To cover front and flanks of attacking troops. 
In frontal screens care must be exercised to place 
the smoke screen, preferably on the enemy trench 
system, so that an enemy barrage laid on the screen 
will not catch our own advancing troops, (c) As a 
feint to draw the enemy's attention to a front which 
it is not expected to attack, causing him needlessly 
to retain troops and expend ammunition, (d) De- 154 
GAS WARFARE 
ceptive screens to simulate general or local attacks. 
Gas should generally be used with smoke in these 
cases. A proper use of gas in connection with 
smoke screen work will cause the enemy to expect 
gas whenever smoke is used. This offers a tremen- 
dous advantage to our own troops, (e) To con- 
ceal concentrations of our guns and troops, and to 
screen roads and movements, (f) To cover con- 
struction of bridges and trenches in the face of the 
enemy. 
The use of smoke should be such as to lead the 
enemy to expect or anticipate some object other than 
the real one. 
The Stokes Mortar.-The mortar gas bomb is 
adapted to any of the cases set forth above. The 
mortar is especially useful in an active offensive 
where its mobility permits it to be pushed far for- 
ward and brought into operation on short notice. 
With efficient transport, gun teams can readily fol- 
low the reserve battalions of attacking regiments 
and be brought into action when required on enemy 
machine-gun nests or concentrations within two 
hours. This weapon is particularly adapted to the 
formation of local high concentrations, and is one 
of the best means of silencing hostile machine guns 
or minenwerfers within range. The smoke bomb 
is used effectively under all conditions given above. 
The mortar thermit bomb is used primarily for its 
demoralizing effect, against enemy machine-guns, 
of concentrations within range It is not as effective 
as gas, but can be used irrespective of wind direc- 
tions. It may at times be used where conditions are 
unfavorable for smoke, or in addition to smoke, on GAS WARFARE 
155 
strong points, trench intersections, and machine- 
guns. It has a considerable terrorizing effect. 
The Projector.-The projector gas drum, with 
its thirty pounds of gas, is an excellent weapon 
for producing high concentrations in surprise shoots. 
It is especially effective against enemy concentra- 
tions, in villages and woods. 
Due to its longer range, it can be used when 
Stokes mortars cannot. On the other hand, the 
weight and bulk of the equipment hinder its use 
on a rapidly moving front. With a length of carry 
not to exceed 500 meters from the limit of mortar 
traffic to the emplacements, from 100 to 150 pro- 
jectors can be installed and discharged in one night 
by one company. This makes the projectors an 
efficient weapon during temporary checks, or dur- 
ing organizations and consolidation of the line. 
Projector drums filled with high explosive may 
be used whenever wind conditions prevent the use 
of gas. They contain large charges in a case which 
is much lighter than an artillery shell, and are very 
deadly against troops in the open. They may also 
be used to demolish wire. 
Cylinders.-A cylinder gas attack against suit- 
able targets is undoubtedly the most effective means 
of using gas. High concentrations may be estab- 
lished over wide areas, and to depths of 10 or 15 
kilometers. Even when the enemy has been aware 
that an attack was probable, there have been casu- 
alties amounting to nearly 10% of the enemy forces 
in the area affected. In addition, the gases, being 
highly corrosive in high concentrations, attack the 
metal parts of all guns and rifles. A cylinder at- 156 
GAS WARFARE 
tack, with a suitable wind, may be made imme- 
diately preceding an attack along the entire front. 
It can be closely followed by the infantry and will 
succeed in thoroughly breaking the defense. 
Training of Gas Troops.-In the training of 
gas troops it must be kept constantly in mind that 
they are strictly fighting troops who will be required 
to carry on their operations in the foremost areas. 
They must be trained to insure correct technical 
execution with their special equipment, as well as 
to know how to handle themselves in action as In- 
fantry, and take care of themselves in all emergen- 
cies of front line work. 
The course as outlined herein is of the most in- 
tensive character, but must be considered of an 
emergency nature made necessary in order to place 
troops in action at the earliest practicable moment. 
In addition, the assumption is made that the 
troops are organized and equipped, have a full com- 
plement of officers and at least half of their non- 
commissioned officers, and that they have received 
preliminary instructions, including the simpler close 
order movements up to and including the Battalion 
Parade. 
The course is divided into two phases, the first 
consisting of eight weeks and the second four weeks. 
The first phase consists of the school proper and is 
divided roughly as follows: (a) Four weeks or 
forty-four drill periods devoted to special training 
in the use and operation of the special equipment, 
(b) Two weeks or twenty-two periods to infantry 
training, (c) Two weeks or twenty-two periods 
devoted to target practice, instruction and firing. 
The second phase covers four weeks, during GAS WARFARE 
157 
which platoons or sections are attached to units of 
experienced troops actually operating at the front. 
During this phase troops under instruction will as- 
sist the experienced troops by providing additional 
labor and gradually working into the operations, 
fixing the work of the first phase definitely in all 
details, under the conditions met with in actual op- 
erations at the front. Where it is impossible to do 
this, an additional four weeks should be allowed 
and the entire phase used in improving discipline, 
technical execution, and the carrying out of opera- 
tions under all simulated conditions, of front line 
work. 
Underlying all instruction must be a keen fighting 
spirit. Both officers and men must be made to ap- 
preciate from the very start that the ultimate and 
sole object of the work of this organization is to 
produce enemy casualties and assist other organiza- 
tions to produce enemy casualties. Its success and 
value to the Army and country can be measured 
directly in enemy casualties. Gas troops are care- 
fully instructed in their part in the team work neces- 
sary to the success of tactical operations in which 
they may be engaged, especially in the necessity of 
giving loyal and faithful service to the command- 
ing officer of the infantry unit under whose orders 
they may be directed to operate. 
Officers and men must appreciate that absolute 
discipline, and compliance with orders and instruc- 
tions, are not only essential to greater direct success, 
but also afford the only real means of pro- 
tection against large casualties in our own per- 
sonnel. The men must not be allowed to drill in an 
indifferent or aimless manner. The picture of ac- 158 
GAS WARFARE 
tual combat must be kept in the mind of the in- 
structor and transmitted to those undergoing in- 
struction. 
Lectures are reduced to a minimum, made brief 
and whenever possible given in connection with ex- 
planations and demonstration of equipment in the 
field. Gas defense training is continued during the 
entire course of training, using any available time 
and under conditions which will leave every man 
capable of protecting himself in extreme emergency. 
School Phase.-It is essential that the officers 
who are to actually lead the troops be trained with 
them, and know their men. This necessitates di- 
viding the personnel into six classes, dividing along 
tactical lines of the units where possible. These 
classes are as follows: 
Class A-One-half of commissioned personnel. 
Class B-One-half of commissioned personnel. 
Class C-One-half of non-commissioned per- 
sonnel. 
Class D-One-half of non-commissioned per- 
sonnel. 
Class E-One-half of remainder of units. 
Class F-One-half of remainder of units. 
Classes A, B, C and D are given sufficient actual 
field training with the special equipment to insure 
not only a thorough understanding, but also correct 
mechanical execution. Officers are trained sepa- 
rately from the other ranks, and are required to 
actually handle and carry loads, use the pick and 
shovel, and do all the practical work. They also 
carry out operations, including transportation of 
material, both before and after the operation. 
Throughout the course of instruction the strictest GAS WARFARE 
159 
attention is paid to discipline, the routine adminis- 
tration of the units, and in as far as possible, the 
routine functioning of officers and men. Strict at- 
tention is paid to the performance of guard duty. 
Messing arrangements are carefully supervised and 
additional training given in the handling of rations. 
Billeting of the men is given careful consideration. 
Sanitation and proper policing is carefully watched. 
Bathing of the men is done by schedule and super- 
vised. 
In the general training stress must be laid on the 
absolute necessity of learning routine administra- 
tion, the proper handling and care of men under 
the better conditions of the rear areas, or training 
camps, so thoroughly that both officers and men will 
be able to take care of themselves under the adverse 
conditions of the front line work. Discipline and 
insistence on the performance of every detail of 
this work is essential. 
Infantry Training.-This includes (i) Physical 
Training. (2) School of the Squad. (3) School 
of the Platoon. In the work of the gas troops 
the platoon is the working unit and it should be an 
entirety in itself. It should be trained as a unit and 
should work together. It should be so organized 
that it can undertake independent operations. (4) 
School of the Company and the Battalion. Cere- 
monies should be given a prominent place in the 
schedule. As the training progresses and the units 
are split up undergoing technical training, the pa- 
rade and review offer the best means of keeping the 
men set up and snappy. (5) Guard Duty. Formal 
guard mounts should be held. Especial care must 
be taken in the instruction of sentinels; they must 160 
GAS WARFARE 
be made to realize the serious nature of their charge 
when posted as sentinels, in time of war. Any lax- 
ity in the training area may result in the gravest 
offense in the forward area. (6) Extended Order. 
In the close order work correct execution should be 
the keynote. This should be obtained at once, and 
the extended order taken up at the earliest oppor- 
tunity, maintaining just sufficient close order work 
to keep the men set up and in hand. Extended 
order instruction should progress as rapidly as is 
consistent with correct execution to field maneuvers 
with especial reference to service of security, pa- 
trolling, inter-communication and thorough con- 
trol. (7) Full Marching Order. In forward areas 
the men will be required to make many marches 
under full pack, frequently bivouacking in the open. 
They will be trained how to carry the essentials, 
and only the essentials, as well as how to go into 
bivouac and take care of themselves. Only by doing 
this frequently, and under the closest supervision, 
will it be possible to carry on efficiently forward 
where every ounce of energy of both officers and 
men must be conserved. (8) Fighting Order. Men 
should be required in all field operations to go 
equipped as they would actually go into action, with 
the exception of rifle ammunition, which should be 
used during the last week of their training, but after 
they have had range practice. (9) Gas Defense 
Training. In the first drill periods careful instruc- 
tion must be given in the correct mechanical adjust- 
ment of the respirators. This instruction must be 
followed up during the entire period of training by 
frequent drills so as to insure prompt and correct 
adjustment under all conditions. This is of special GAS WARFARE 
161 
importance in night work, and night marches should 
be made with the respirators adjusted. Men should 
be trained to fire Stokes mortars with respirators 
adjusted. Instructors should pay special attention 
to requiring men to adjust the mask at odd times 
when engaged on other work, such as digging in 
projectors, carrying material forward, and the like. 
The use of a mild lachrymator will materially 
assist in showing the importance of this work and 
assist in checking up delinquencies. 
Liaison.-It is very important to select smart, 
intelligent men as runners. They should be men 
who are above the average in soldierly qualities, 
but not mature enough for non-commissioned rank. 
They should receive the same trainnig as other en- 
listed men, but when they have learned the technical 
work and drill, they should be given special instruc- 
tions in map reading, use of the compass, finding 
their direction at night, and carrying verbal mes- 
sages from Battalion or Company Commanders to 
Company Officers without any alteration. 
During practice operations on the training 
ground they should be used by the officers in con- 
veying code messages relating to the operation and 
they should be practiced at night, getting across 
country after dark. 
Each officer selects and trains two runners for his 
own use. He is responsible that these men are fit 
for the job, and that.they realize the importance of 
the duties in hand. 
When companies move up to battle positions, 
these men are required to accompany officers on 
reconnaissances of the advanced line, to act as 
guides for carrying parties, as runners attached to 162 
GAS WARFARE 
an assaulting battalion, or left as runners to wait 
important messages at a Divisional, Brigade, Regi- 
mental or Battalion Headquarters. When on the 
last mentioned duty, they must not leave the mes- 
sage center or headquarters day or night until re- 
lieved. 
They must have a good sense of direction and 
be able to find their way over desolate country at 
night with few visible landmarks. 
When moving about in the advance zone an of- 
ficer is accompanied by at least one runner, so that 
the latter will have a thorough knowledge of the 
country and be in a position to convey messages' 
from his officer at any later time to the company 
headquarters, or to any infantry headquarters. 
This is especially necessary during an operation 
where the officer is busily engaged in his work of 
preparation, and has to send back reports of prog- 
ress of same. 
Service of Security and Information.-This 
should follow the principles laid down in the Field 
Service Regulations with special attention to the 
following: 
Secrecy.-The success of these operations de- 
pends largely upon the attack being a complete sur- 
prise to the enemy. Codes must be used. Care 
should be exercised in the use of telephones. Tele- 
phones should not be used for conversation in 
"clear" or at regular intervals, as in the transmis- 
sion of meteorological data. When operating with 
other units in the line greatest care must be exer- 
cised so as not to indicate increased activity. The 
regulations in force in the particular sector must 
be strictly complied with. GAS WARFARE 
163 
Camouflage.-The simpler principles should be 
covered which will allow an officer to decide as to 
color and texture of material, quantity and dimen- 
sions of artificial material, as well as to make the 
best out of natural concealment in woods and acci- 
dents of the terrain. Track discipline is of especial 
importance. The position should never be left 
either before or after firing before it is thoroughly 
camouflaged. Frequent aerial photographs should 
be obtained as work progresses on the larger oper- 
ations. 
Meteorology.-There are certain fundamental 
principles in meteorology which every officer should 
understand. All gas operations are dependant in 
more or less degree upon wind and weather condi- 
tions, but with an understanding of the simpler 
principles and complete data, not only from the 
Meteorological Service itself, but from that ob- 
tained by the Meteorological Sections of the units 
themselves, it is possible to predict and make a much 
larger use of gas than would otherwise be possible. 
This is so important and will be of such greater 
importance in future operations that this knowledge 
must be obtained. The safety limits must be thor- 
oughly understood. 
Service of Supply.-Under this should be cov- 
ered all the details of supply, whether automatic 
or otherwise, and a definite understanding had as to 
the procedure in each case. 
Map Reading and Making.-It is not only dis- 
graceful but criminal for an officer to take his men 
into action over unfamiliar ground without the 
ability to keep himself properly located at all times. 
Organization of an Attack.-Operations such 164 
GAS WARFARE 
as the gas troops must carry out frequently neces- 
sitate the movement of large amounts of material 
and use of a considerable number of men. As in 
any other operation it requires careful planning 
and organization. Time is an essential element and 
must always be taken into consideration. If nor- 
mal contingencies are allowed for, the adverse con- 
ditions of front line work will usually add sufficient 
difficulties to tax the energy and ability of all con- 
cerned without allowing for mistakes and lack of 
supplies. 
Writing of Orders.-All officers must be trained 
to write clear, complete and correct orders covering 
units which they will be expected to lead. After a 
thorough explanation of the necessity and the de- 
tails to be covered in an order, practical instruction 
in connection with actual operations undertaken in 
the general training will usually suffice if these or- 
ders are carefully checked and mistakes corrected. 
Meteorological Section.-Eight men in each 
battalion should be thoroughly trained to take and 
properly record meteorological data. They should 
know how to interpret data received from the 
Meteorological Service and apply it to local condi- 
tions. A regular system should be instituted in each 
battalion and company so as to keep all officers 
thoroughly informed as to wind and weather con- 
ditions. 
Runner Service.-Each battalion and company 
should have four trained runners and each platoon 
leader two trained runners. These men should be 
carefully selected, intelligent and resourceful. They 
must be instructed in the operations of the units 
and their relation to the other troops with which GAS WARFARE 
165 
the unit is operating. They should be trained to 
carry messages correctly under the most adverse 
conditions, and must be made to realize that upon 
their work the failure or success of an operation 
may depend. CHAPTER XII 
Use of Gas by the Air Service, Tactical Use of Incendiary 
and Smoke Bombs, Altitude Flying and Oxygen Ap- 
paratus, Chanard Incendiary Bombs, Training Smoke 
Bombs. 
When the United States entered the European 
war no satisfactory incendiary bombs had been 
produced by any country, and consequently a long 
period had to be given over to experimentation be- 
fore quantity production could be attained. In due 
time two types of incendiary bombs were produced, 
the first being of the scatter type, designed for use 
against light structures, grain fields, and the like, 
and the second of the intensive type for use against 
large structures and well defined targets. The 
American intensive bombs weighed about 40 pounds 
each and contained charges of oil emulsion, ther- 
mit, and metallic sodium, a combination of chem- 
icals that burns with intense heat. These bombs 
were used against ammunition depots or any struc- 
tures of an inflammable nature. The sodium in the 
charge was designed to have a discouraging effect 
upon any one who attempted to put out the fire of 
the burning charge, since metallic sodium explodes 
with great violence if water is poured upon it. 
One of the interesting phases of the bomb man- 
ufacturing program grew out of the necessity for 
target practice for aviators. For this work dummy 
166 GAS WARFARE 
167 
bombs of terra cotta were built, costing about a 
dollar apiece. Instead of loading these bombs with 
explosive, there was placed in each a small charge 
of phosphorus and a loaded paper shotgun shell, 
so that the bomb would eject a puff of smoke when 
it hit its object. The aviators could see the smoke 
puffs and thereby determine the accuracy of their 
aim. 
Night-flying is one of the most hazardous duties 
of the aviator, the chief danger being in landing. 
The aviator at night can usually see the ground 
faintly, but he is unable to make an accurate judg- 
ment of the distance of his machine above the 
ground. This danger is greatly alleviated when 
wing-tip flares are used. The wing-tip flare con- 
sists of a small cylinder of magnesium material in 
a metallic holder, one flare being fitted under each 
lower wing of the plane and being controlled by a 
push button in the pilot's cockpit. Pressure on the 
button sends an electric spark into the magnesium 
and touches it off. When ignited the flare burns 
for about 50 seconds with the brilliant light of 
20,000 candle power, the reflection from the under 
surface of the wing lighting up the field for an 
adequate distance in all directions. 
To enable the night bomber to see his target a 
piece of pyrotechnics known as the airplane flare 
is employed. This is a great charge of magnesium 
light held in a cylindrical sheet-iron case nearly 
4 feet long and 5 inches in diameter, and weighing 
32 pounds. Within the cylinder is not only the 
magnesium stick but also a silk parachute, 20 feet 
in diameter. The entire cartridge is attached to 
the airplane by a release mechanism similar to those 168 
GAS WARFARE 
holding the drop-bombs. When over his objective 
at night the pilot or observer touches a button and 
the entire cartridge, iron case and all, drops from 
the plane. A pin wheel on the lower end of the 
case is instantly spun by the rush of air, and the 
resulting power not only ignites the magnesium but 
at the same time detonates a charge of black pow- 
der sufficient in force to eject from the case the 
flare and its tightly rolled parachute. The para- 
chute immediately opens; and the burning flare des- 
cends slowly, flooding a large area of the ground 
below with a light of 320,000 candle power, this 
light burning for about ten minutes. Such a light 
not only enables the bomber to drop his destructive 
missiles accurately, but dazzles the eyes of anti- 
aircraft gunners below and makes their aim inac- 
curate. The light of this flare is so strong that 
it is possible for the airplane above to obtain pho- 
tographs of good detail on the darkest of nights. 
The first oxygen apparatus for high altitude 
flying was designed for the British Air Service, 
and the first squadron which used the apparatus 
reported that its men gave six times the service of 
any other British squadron. The American Air 
Service adopted the Dreyer oxygen apparatus, 
which was the original device produced by the Brit- 
ish. The first British apparatus was heavy and 
built to supply oxygen to one man only. It was 
afterwards reduced in weight, changed to take care 
of two men and re-designed to meet American fac- 
tory methods. In its present state of development 
this equipment consists of a small tank or tanks, 
the pressure apparatus, the tube leading from the 
reservoir, and the face mask covering the mouth GAS WARFARE 
169 
and nose. The mask has combined with it either 
the interphone, a mechanism which cuts off the roar 
t>f the engine from the ears of the passengers and 
allows the pilot and observer to talk freely with 
each other, or in certain cases the receiver of the 
radio telephone or telegraph. All military planes 
(day and night bombing, pursuit, chasse, and Army 
and Corps observation planes) flying above an alti- 
tude of 10,000 feet are required to be equipped 
with oxygen apparatus. 
French Chanard Incendiary Bomb.-This 
bomb, of the intensive type, is commonly employed 
by the American Air Service, and consists of a case 
or body, nose, stabilizer wings, H tube, quick match, 
tubes, vents, firing mechanism and safety propeller. 
Construction.-The bomb body or case is com- 
posed of two longitudinal halves of an ellipsoid of 
revolution. The edges of these are soldered to the 
annular core or H tube. Both the body and the H 
tube are made of tin plate. The H tube is filled 
with special thermit mixture, which is known as 
C. D. powder or Daisite No. 2. The charge is 275 
grams. The main body is filled with Chanard in- 
cendiary material. This material consists of a plas- 
tic semi-fluid mass which on combustion flows 
freely. It consists principally of nitrocellulose and 
resin with a mixture of turpentines. 
Firing Mechanism.-This consists of a safety 
propeller with screw and plug into which screws a 
socket, striker, striker spring, three steel balls, 
striker sleeve, and quick match or fuse in the tube. 
Method of Operation.-During shipment the 
propeller is held stationary by two strands of wire 
attached respectively to the propeller and the body 170 
GAS WARFARE 
of the bomb. The firing mechanism is permanently 
locked by means of a propeller screw which abso- 
lutely prevents accidental functioning. Before the 
bomb is placed in the suspension on the plane, the 
wires which hold the propeller are removed and 
the propeller unscrewed by no more than four com- 
plete turns. The bomb is then placed in the sus- 
pension where the propeller is prevented from re- 
volving by means of a spring wire which engages 
the blades. The firing mechanism consists prin- 
cipally of a striker driven forward by a spring. 
The tail of the striker, which is hollow, is held in 
place by three equi-distant balls separated by the 
thickness of the striker. These balls are held in 
place between the vertical wall and the striker sleeve 
and the propeller stem. As the propeller unscrews, 
the stem moves with almost no frictional resistance, 
until the lower end passes the equator of the three 
balls. At that moment the striker spring comes into 
play. The balls drop into the striker and the striker 
is driven with considerable force against the de- 
tonator. 
Action.-As the bomb is released from the air- 
plane, the current of air produced by the falling 
body, unscrews the propeller. Five seconds later, 
that is to say, at a distance of from 60 to 80 meters 
from the machine, the firing mechanism is auto- 
matically unlocked and immediately the 8-second 
fuse or quick match contained therein is ignited. 
When that time has elapsed and the bomb has des- 
cended some 500 meters or more, the firing mechan- 
ism is blown off by a slight explosion and the ma- 
terial in the H tube is ignited at four different 
points. The bomb is split in two halves by melting GAS WARFARE 
171 
the solder and the main incendiary mass is ignited. 
As this action takes place, the bomb is still dropping 
through the air, and it reaches its target in flames. 
The blazing contents are deposited on the target 
without the necessity of an explosion. Here it 
continues to burn for some 18 minutes. A black 
smoke is given off which hinders fire fighting. 
Marking.-The bomb is painted with light red 
oil paint. Around the vent holes are painted white 
circles and on the body of the bomb are the mark- 
ings "C. D. 120." 
When these bombs are removed from the case, 
they should be lifted by their suspension keys. If 
replaced, they should be deplaced in a horizontal 
position with the suspension keys crossed. 
The Chanard Incendiary Bomb is so designed 
that it will penetrate an ordinary roof and deposit 
its contents in the interior of the building. The 
incendiary material of the bomb being already ig- 
nited when it hits the target, it continues to melt, 
run and burn as it runs communicating this fire to 
any inflammable material which it reaches. A 
bomb of this type should, of course, be used only 
against well defined targets where a direct hit is 
possible, for if it should miss the target and strike 
on the ground or other uninflammable material its 
effect would be nil. 
Incendiary Bombs of the Scatter Type possess 
the advantage of not requiring a direct hit, because 
the material scatters to a certain extent; but they 
possess a disadvantage in that the amount of in- 
cendiary material in any one place is small and un- 
less the material is quite inflammable it will not be 
set on fire. GAS WARFARE 
172 
French Training No. 2 Smoke Bomb, Steel.- 
This bomb consists of a firing pin, shear wire, safety- 
pin, cartridge plug, gaine head, steel ogive, 10 cali- 
ber cartridge, filled with "T" powder, sheet steel 
body, gaine tube, ballast of cast sulphur, stabilizer 
wings, tin tube containing titanium tetrachloride, 
cork plug, cement plug, and cotton wad. All the 
metal parts are made of steel or iron. MT" powder 
is a highly nitrated sporting powder containing less 
than 1.3% moisture. 
Method of Operation.-The bomb is designed 
so that it has the same trajectory as regular bombs 
and is used to train aviators in bomb dropping. 
When suspended in the dropping mechanisms the 
safety pin is removed. On striking the objective 
the shear wire is cut and the firing pin impinges 
on the detonator of the cartridge, which is thereby 
fired. This expels the tin tube containing the fumi- 
gen and at the same time breaks it, causing a scat- 
tering of the liquid titanium tetrachloride, which 
substance produces a white cloud of smoke visible 
from the airplane. 
Marking.-The bomb is painted black, but has 
no special markings other than the Inspector of the 
Forges. 
French Training Smoke Bomb, Cement.- 
This bomb is a modification of the foregoing steel 
smoke bomb. It has narrower stabilizer wings and 
a more streamlike shape. A different gaine head is 
used and the gaine reinforcing tube is done away 
with. The main difference between this bomb and 
the French Training No. 2 smoke bomb, steel, is 
that the body is made of cement rather than of 
steel filled with cast sulphur, and that the gaine GAS WARFARE 
173 
tube has a reinforcing tube near the nose end in the 
older model. 
Method of Operation and Marking.-The 
method of operation and marking is the same as 
for the French Training No. 2 smoke bomb, steel, 
except that the stabilizer wings only are painted 
black, the body being unpainted. 
These bombs are designed for use only in train- 
ing bomb droppers in the use of bomb sights and 
release mechanism. On impinging on the ground 
the bomb expels its charge of fumigenite (titanium 
tetrachloride) which gives a smoke cloud which is 
visible to the bomb dropper in the plane, thus in- 
forming him as to whether or not he has hit the 
desired target. CHAPTER XIII 
Gas Zones, Gas Alarms, Gas Sentries, Action during and 
after Gas Attack, Division Organization of Disinfect- 
ing Service, Duties of Regimental and Battalion Gas 
Officers. 
Two zones, known as the "Alert" and "Danger" 
zones, are defined in the area of the armies. The 
approximate extent of these zones is as follows: 
Alert Zone.-The area within three kilometers 
of the front line, together with areas especially sub- 
ject to shelling with gas, including all active bat- 
tery positions and other points, such as villages, 
cross roads and convenient concentration points for 
troops, to be designated by the Division Gas Officer. 
Danger Zone.-The area between three and ten 
kilometers to the rear of the front line. 
Within the alert zone all persons in or con- 
nected with the military service wear the respirator 
in the "Alert" position. Every man is clean-shaven, 
except that a mustache may be worn, and the hair 
is kept short in accordance with Army Regulations. 
Sleeping men must not remove the respirators from 
their bodies. A sufficient number of sentries must 
be posted to awaken all men quickly in case of a 
gas attack. Respirators and all gas defense appli- 
ances will be inspected daily in this zone. Horse 
respirators are worn in the "Alert" position. 
Within the danger zone, troops carry their re- 
174 GAS WARFARE 
175 
spirators at all times, except when asleep, in which 
case the respirators are within immediate reach. 
Respirators and gas defense appliances are inspect- 
ed three times a week. Horse respirators are worn 
in the "carry" position over all equipment. 
Sentinels and military police are instructed to 
allow no person connected with the Military Service 
to pass without complying with all the rules re- 
lating to the wearing of respirators. They report 
all cases of infringement of the above orders, and 
copies of these reports are furnished to the regi- 
mental or divisional gas officers. 
The above-named zones are conspicuously 
marked by each regiment in such a manner as to at- 
tract the attention of persons entering them. When 
not carried in the "Alert" position, the box respira- 
tor is carried in the slung position, this is, over the 
left hip, the sling passing over the right shoulder. 
Nothing is worn so as to interfere with the im- 
mediate shifting of the respirator to the "Alert" 
position. 
An efficient system of gas alarms is provided 
throughout the "Danger" zone, and especially in 
the "Alert" zone. This includes Klaxon horns, rat- 
tles and triangles, together with other signals ap- 
proved for this purpose by the Division Commander 
on recommendation of the Division Gas Officer. 
These alarms are used solely for the purpose of 
giving warning in case of a gas attack. When 
necessary, civil authorities within divisional areas 
are warned by Division Headquarters. Any person 
becoming aware of the presence of gas or of an im- 
pending gas attack gives alarm by means of the 
alarm signals or by calling "Gas." Any one who 176 
GAS WARFARE 
knowingly gives a false gas alarm is tried by court- 
martial. 
All sentries act as gas sentries, and if neces- 
sary, special gas sentries are posted in order that 
the alarm may be promptly and properly given. 
Special gas sentries have definite areas to alarm in 
the event of a gas attack. Two sentinels are posted 
at night. When deemed necessary one of them 
wears the respirator completely adjusted. They re- 
lieve each other of wearing the respirator every 
half hour. All working parties of ten or more men 
have a gas sentry posted. All sentries, traffic con- 
trol men, military police, etc., when on duty act as 
gas sentries, and are provided with suitable alarm 
devices when necessary. Sentries are posted over 
all men sleeping and all men in dugouts or shelters, 
and each sentry is definitely responsible for the 
group assigned to him. The loss of a few seconds 
in giving gas alarms may increase very greatly the 
number of casualties. In case of gas attack, sen- 
tries shout "Gas!", put on their respirators and then 
give the alarm. If possible, sentries should be 
placed in positions overlooking the enemy lines to 
detect the characteristic flash which accompanies a 
projector attack. Sentries should be carefully in- 
structed in methods of detecting the various forms 
of gas attacks, such as the hissing sound accompany- 
ing cloud attacks, and the flash, loud explosion and 
whirring of projectiles in a projector attack. In 
case of doubt, especially when a projector attack 
is suspected, alarm is given. As frequent false gas 
alarms will eventually cause troops to disregard an 
alarm, gas sentries are carefully selected and thor- GAS WARFARE 
177 
oughly in >tructed, so that false alarms are reduced 
to a mini num. 
Any concentration of troops within 1500 yards of 
the enemy lines should be avoided, unless the tacti- 
cal situation so requires. Within this area every 
precaution must be taken to avoid giving informa- 
tion to the enemy of localities in which troops are 
concentrated, since such points of concentration 
are chosen as targets for projectors. 
At the instant that any gas alarm is given, all 
ranks immediately put on respirators and wear them 
until the order to remove masks is given by an of- 
ficer acting upon the advice of a Gas Officer. In 
the case of isolated groups and in the absence of 
a Gas Officer, the order to remove masks is given 
by the non-commissioned officer in charge, who will 
report this action promptly to the nearest officer. 
In case the gas attack is followed by an assault 
of enemy infantry not wearing masks, respirators 
may be removed without formal order. Any officer 
or man who fails to put on his respirator when 
warned by a Gas Officer or by a general gas alarm 
of the presence of gas, or who removes his re- 
spirator without proper authority, is disciplined. 
If a person under such circumstances becomes a 
casualty, he is considered as wounded "not in the 
line of duty." 
The blanket curtains of protected dugouts and 
cellars are properly adjusted, fires in such dugouts 
put out and dues closed. The organization attacked 
at once notifies battalion headquarters and troops 
on the flank of the attack. Battalion headquarters 
in turn notifies regimental headquarters and the 178 
GAS WARFARE 
Regimental Gas Officer. Regimental headquarters 
notifies divisional headquarters of all gas attacks. 
Additional spreading of the alarm takes place 
when necessary. No one enters a gassed area 
into which he is not obliged to go in line of duty, 
and all who are within a gassed area refrain from 
all movement and conversation not required by mili- 
tary necessity. 
When the tactical situation permits, troops not on 
duty should be allowed to remain in gasproof dug- 
outs, and to remove their masks, if the dugout is 
entirely free from gas. An additional sentry must 
then be posted inside the dugout at each entrance 
until the area is free from gas. All unnecessary 
movement and talking must cease. In case of a 
cloud gas attack, all bodies of troops or transport 
on the move will halt, and working parties cease 
work until the gas cloud has passed. If a relief 
is in progress, units should stand steady as far as 
possible until the gas cloud has passed. Supports 
and parties bringing up ammunition and grenades 
are only moved up if the tactical situation demands. 
As soon as possible after or during a gas attack, 
gas officers determine whether a "persistent" or a 
"non-persistent" gas is being employed. When the 
situation permits a position extensively bombarded 
by the most persistent gas, namely, mustard, must 
be temporarily evacuated. 
If mustard gas is used, the area is dangerous, for 
one or two days, and sometimes longer, unless the 
tactical situation forbids, and an area subjected to 
such a gas attack should be promptly evacuated for 
a period of three days, or until pronounced safe by 
the Divisional or Regimental Gas Officer. If prac- GAS WARFARE 
179 
ticable, the Division Gas Officer will be consulted. 
The evacuation should be made upward from the 
shelled area when possible. For this reason alter- 
native positions should be selected in advance, and 
all the necessary preparatory steps should be taken 
to accomplish a rapid and orderly change to such 
positions in case of necessity. 
In case a position shelled with mustard gas must 
continue to be occupied, respirators are worn con- 
tinuously, men must not be permitted to sit or lie 
upon contaminated ground, and other precautions 
must be taken to avoid contamination of the body 
or clothing. In such a case, frequent reliefs should 
be established. After a gas attack, gas officers take 
immediate steps to clear and disinfect gassed posi- 
tions. They report when the position is safe. As 
long as the slightest odor of mustard gas is detect- 
able, the position must be considered dangerous. It 
is especially to be noted that the odor of mustard 
gas in slight concentrations is not unpleasant, and 
that the gas produces no irritation for several hours. 
During a mustard gas attack, precautions must be 
taken to avoid contamination of dugouts from the 
clothing and especially from the shoes of men who 
enter. Men who have been even slightly gassed arq 
treated as casualties, and withdrawn promptly from 
the gassed area with the least possible exertion on 
the part of the man gassed. Especially in the case 
of a mustard gas attack, it is important that fresh 
clothing be available and that the clothing should 
be changed and the man given a bath with soap and 
water as soon as practicable. 
After a gas attack, food supplies which have been 
exposed should be thoroughly inspected, and any 180 
GAS WARFARE 
food suspected of contamination with gas should 
be condemned. Many casualties have been caused 
by the use of water from shell holes. Regardless 
of whether recent gas attacks have occurred, all 
water from shell holes must be regarded as con- 
taminated, and must never be used for any pur- 
pose whatsoever. 
It is customary for a gas attack to proceed in 
waves or salvos at variable intervals, therefore, a 
sharp lookout is maintained for a repetition of a gets 
attack. When the tactical situation permits, troops 
which have been subjected to gas attacks are with- 
drawn. Commanders of units relieving one an- 
other are responsible that all the anti-gas stores are 
handed over and receipted for by the respective gas 
officers of the units. 
In order to provide the most efficient means for 
the purification of ground which has been shelled 
with "mustard gas" special disinfection squads are 
designated and trained by each Regimental or Bat- 
talion Gas Officer for this purpose. These squads 
are organized in the various units according to the 
tactical employment of these units; each squad to be 
under the immediate directon of the gas non-com- 
missioned officer of that unit. Except in case of 
"mustard gas" shelling, the men composing this 
squad are free to perform their regular duties. This 
does not apply to the gas non-commissioned officers, 
who are assigned no duties which might interfere 
with their duties as gas non-commissioned officers. 
These men, however, spend such time as may be 
necessary in order to make them proficient in their 
work, according to the discretion of the Regimental 
Gas Officer. The duties of these disinfecting squads GAS WARFARE 
181 
are to disinfect "mustard gas" shell holes with 
chloride of lime and to cover this chloride of lime 
with earth; to bury leaking gas "duds;" to mark the 
location of sound gas "duds," which location is 
given the Regimental Gas Officer; and to carry out 
infected equipment and clothing from "mustard 
gas" infected barracks or dugouts, when an evacu- 
ation has been ordered. 
Field hospital, ambulance and signal companies, 
and other units attached to the Division are looked 
after by the disinfecting party in whose area they 
are operating. The equipment for each man in the 
disinfecting squad, in addition to the small box 
respirator, consists of a suit of special oiled cloth- 
ing and two pairs of oiled gloves. Immediate dis- 
infection is necessary to prevent mustard gas casu- 
alties, and every effort should be made to expedite 
the arrival of a disinfecting squad at a shelled 
area. 
The following is a typical memorandum of the 
duties of regimental and battalion Gas Officers: I. 
Report all gas shelling promptly, giving time, lo- 
cation, weather, wind, and number, size and kind of 
shells used, and any casualties reported. 2. Report 
immediately any mustard gas shelling in your area. 
3. Report promptly all changes in gas personnel. 
4. Report name, rank, and organization of all of- 
ficers violating standing orders of gas defense. 5. 
Insist on daily inspections of respirators in "Alert" 
zone and twice weekly in "Danger" zone. Check 
up these inspections personally to be positive they 
are being carried out. 6. Make sure by frequent in- 
spections and tests that alarms are adequate and in 
working order. 7. Frequent instruction of all sen- 182 
GAS WARFARE 
tries is mandatory. They must be thoroughly famil- 
iarized with all their duties. They must know all 
standing orders of Gas Defense. They must know 
how to detect a gas attack, how and when to give 
the alarm and when to awaken sleeping men over 
whom they may be posted. 8. Make sure that no 
men are permitted to sleep without being near a 
sentry who knows where they are. 9. Question 
and instruct all gas non-commissioned officers fre- 
quently, reporting those (by name, rank, and organ- 
ization) considered incapable, those who neglect 
their work, and those who have too many other 
duties to perform. 10. Make sure that when a man 
loses his respirator or when he turns one in for 
replacement that has been rendered unserviceable 
through carelessness or by intention, the new one 
issued is charged against his pay account, and see 
that further disciplinary action is taken. 11. Make 
sure that all units in each area are well known. 
12. Submit brief report each week covering work 
done during the week as Gas Officer, and, in addi- 
tion, nature of other duties performed and the 
amount of time required for same. 
Company gas non-cofcnmissioned officers assist 
officers at the inspection of respirators, taking par- 
ticular care to see that each man's satchel is marked 
with his own name, and in making such local repairs 
as are possible. They assist in training men in the 
use of gas defense appliances and, under the Com- 
pany Commander, they have charge of all gas de- 
fense trench stores, alarm devices, gasproof shelters 
and stores of fuel for clearing shelters. On relief 
they assist the Company Commander in taking over 
all gas defense trench stores (by daylight, if pos- GAS WARFARE 
183 
sible). They make wind observations as directed 
by the Division Commander on recommendation of 
the Division Gas Officer, and report any change of 
wind to the Company Commander. After a gas 
shell bombardment, if the use of a new gas is sus- 
pected, the gas non-commissioned officer takes sam- 
ples of earth contaminated with the suspected gas. 
Such samples are handed to the Division Gas Of- 
ficer through the Company Commander with notes 
as to the positions from which the samples were 
taken. 
During and after a gas attack the gas non-com- 
missioned officer should note down in writing as 
much information as possible on the following 
points: (i) Strength and direction of wind and 
general weather conditions. (2) Times at which 
the gas wave or gas shell bombardment started and 
finished. (3) Exact position and nature of place 
affected by gas or gas shell. (4) To what extent 
telephone dugouts, covered gun and machine gun 
emplacements, etc., were affected. (5) The approx- 
imate number of gas shell used and their caliber. 
(6) The position of dud shell and fragments of 
shell, etc. CHAPTER XIV 
Respirators, Adjustment and Practice Drills, American 
Tissot Respirator, Fitting and Care of Canisters, 
Anti-Dimming Outfit, Respirators for Horses. 
When training men in the use of respirators the 
following points are of importance: (a) Ordinary- 
infantry drill should be combined with physical 
drill, including arm and leg exercises, leap-frog, 
and double-time. The time of practice need not 
exceed 15 minutes at first while wearing the respira- 
tor, but should be gradually extended. This drill 
should be in heavy marching order, (b) Practice 
in bombing, rapid loading and aiming, judging dis- 
tance and rifle firing, should be carried out while 
the men are wearing respirators, (c) Officers and 
non-commissioned officers should receive the same 
training as the men and in addition, should be prac- 
ticed in giving orders while wearing their respira- 
tors. (d) It must be realized that troops in the line 
always carry the respirator, and that practice in the 
rear should take this into account. Every effort 
must be made to approximate actual warfare condi- 
tions. Every opportunity should be taken to accus- 
tom men to carrying on their usual duties with the 
respirator adjusted. It is often necessary during 
and after a gas attack for men to wear their re- 
spirator for six or eight hours, or even longer when 
184 GAS WARFARE 
185 
a highly persistent gas, such as mustard gas, is used, 
(e) Practice and drill in the use of gas defense ap- 
pliances should be carried out as continuously as 
tactical conditions will permit. This applies espe- 
cially to troops which return to the line after having 
been in rest areas and where the incorporation of 
drafts incompletely trained in gas defense measures 
make such training very essential. 
American Tissot Respirator.-This respirator 
consists of a metal canister filled with a mixture of 
chemical granules and connected by a rubber tube 
to an impervious facepiece. Air is drawn in through 
the inlet valve which consists of a circular rubber 
disc fitted on a stud in the center of a perforated 
metal plate. Any poisonous gas is absorbed by the 
granules in the canister. The purified dry air passes 
into the facepiece, playing over the eyepieces, and 
keeping them clear. Air is expired through the 
outlet valve, the inlet valve closing in order to pre- 
vent air passing through the canister. If the inlet 
valve does not close properly, expired air passes 
into the canister, causing deterioration of the chem- 
icals and discomfort to the wearer. The facepiece 
is held in position by a head harness of self centering 
construction which keeps it firmly against the face 
without discomfort. The complete respirator is 
carried in a satchel which is divided into two com- 
partments, one of which holds the canister and the 
other the mask. The canister rests on a wire plat- 
form which raises it from the bottom of the com- 
partment and allows the free access of air. 
When respirators are issued they should be most 
carefully fitted. In some cases it will be necessary 
to change the length of the elastic by means of the 186 
GAS WARFARE 
buckles. When the fit of the mask appears satis- 
factory, it must be tested in tear gas and the test 
repeated at least every month. If possible, the test 
should be made in the gas chamber every time a 
battalion comes out of the line. Men should re- 
main in the tear gas for five minutes, moving about 
and talking to make sure that the fit of the mask 
is good. When the fit has been tested, each man 
should write his name, but not his organization, on 
the lower part of the front of the satchel as worn 
in the "alert" position to insure that he does not 
exchange his respirator for another that may not 
fit him. 
The most serious causes of damage to the respira- 
tors are: Water entering the canister and spoiling 
the chemicals, injury to the facepiece, and injury to 
the outlet valve. Respirators must be protected 
from wet as far as possible, and rough usage must 
be avoided. Nothing must be carried in the satched, 
except the respirator and anti-dimming outfit; small 
articles of kit readily cause damage to the mask. 
The inside of the facepiece should be wiped before 
it is put away, otherwise damage is caused by the 
rusting of metal parts, and by the rotting of the 
stitching. 
To prevent freezing of the outlet valve during 
very severe frost, two or three drops of glycerine 
should be inserted through the slits at the bottom 
of the valve by means of a match or stick of wood. 
Supplies of glycerine are kept by Division Gas 
Officers for this purpose. Half a pint should be 
sufficient for 1,000 respirators. Inlet valves at bot- 
tom of canisters are not affected if kept dry. If GAS WARFARE 
187 
moisture has entered and frozen, the valve must be 
removed, thawed, wiped dry and replaced. The 
inlet valve must not be treated with glycerine. 
When canisters are issued, they are painted with 
the number of the month of issue. They are then 
replaced after the lapse of a certain number of 
months. They usually become ineffective through 
mechanical damage before they become useless 
chemically. The chemicals in the canister slowly 
lose their efficiency, even when nothing but pure air 
is breathed through them. This is due to the fact 
that the moisture in the air gradually cakes the 
granules, increases their resistance, and lowers their 
absorptive power. When the canister of the res- 
pirator is defective owing to wet, rust, or other 
damage, or has been breathed through for 40 hours 
in gas, and the respirator is otherwise in good order, 
the canister should be replaced by a new one. 
In all operations great care must be taken to 
avoid damaging the rubber tube. Remove the tape 
on the wire. Turn up the twisted end of the wire 
at right angles to the tube. Press on the point of 
the "tool for detaching canister" under a single 
strand of wire near the twisted end. On pressing 
over the tool the wire will be cut by the sharp edge 
inside the V. Remove the wire. Insert both points 
of the V under the rubber, then, with the handle 
of the tool at right angels to the tube, move the tool 
around the neck to loosen the rubber from the 
metal. On continuing with an upward movement 
the tube will be detached. When fixing the new 
canister remove the plug of cotton waste from the 
neck of the new box, lick the neck and slip the rub- 188 
GAS WARFARE 
ber tubing over it so that the neck is completely 
covered, taking care that the facepiece is in the 
correct position relative to the canister. 
The following drills are designed to teach officers 
and men to adjust their respirators accurately and 
quickly. The drill must be so thoroughly mastered 
that all will protect themselves instantly and almost 
automatically upon hearing the gas alarm. 
Drill "A." To bring the Respirator to the 
"Alert" position. 
i. Slung Position.-Respirator with sling over 
right shoulder. Satchel hanging on left side with 
press buttons closed and next to the body. 
2. Gas Alert Position.-Being at "slung" posi- 
tion, (i) Gas Alert. Place the rifle between the 
knees. Slip the left arm back through the sling and 
bring the satchel around to the front of the body. 
Open the flap of the satchel. Take out the whip- 
cord with the right hand and pass it through the 
metal loop on the right hand side of the satchel. 
Raise the satchel to the chest with the left hand so 
that the slack of the sling falls over the back, pulling 
it down with the right hand and holding it there. 
Then take the sling in the left hand and with the 
right, pass the cord through the sling, then through 
the metal loop on the left side of the satchel and 
fasten it tightly with both hands after adjusting 
respirator to proper height on the chest. Fold flap 
over top to protect respirator from wet, but do not 
fasten. 
3. Alternative Position, Especially When 
Pack is Slung.-Being at "slung" position. (1) 
Gas Alert. Place the rifle between the knees. Slip 
the left arm back through the sling and bring the GAS WARFARE 
189 
satchel to the front of the body. With the right 
hand, grasp the metal hook at the left of the satchel 
and with the left hand reach behind the neck for the 
metal eyelet on the sling, pull down and fasten the 
two together. Open the flap and take out whipcord 
with right hand. Pass it through the metal loop on 
the right of the satchel, then around the back and se- 
cure it to the metal loop on the left of the satchel. 
Drill "B." Drill "by numbers" to obtain com- 
plete and accurate adjustment of the respirator from 
the "Alert" position. 
This drill will be alternated with one without the 
numbers to insure as quick an adjustment as pos- 
sible, in which practice in holding the breath will 
be included. The drill must be practiced until com- 
plete and accurate adjustment is obtained by all 
ranks in six seconds. 
The respirator in the "alert" position. The hel- 
met is worn with the strap adjusted at the back 
of the head. One end of a lanyard is attached to 
the left loop of the helmet and the other is passed 
around the left shoulder. 
Being at "alert" position with helmet adjusted: 
(i) By the numbers. (2) Gas. Stop breathing. 
Place the rifle, if unslung, between the knees. In- 
sert the thumbs under flap and open satchel. Seize 
the facepiece with the right hand. Two. Bring the 
facepiece smartly out of the satchel to the height 
of the chin, holding it firmly in both hands with the 
fingers extended outside, the thumb inside at the 
binding midway between the two lower straps of 
the head harness. Stick out the chin. Three. Bring 
the facepiece forward, digging the chin into it. With 
the same motion, guide the straps of the harness GAS WARFARE 
190 
over the head with the thumbs, knocking the helmet 
off backwards. Four. Grasp the outlet valve 
tightly between the fingers, to prevent the passage 
of air through it, and blow vigorously into the mask, 
completely emptying the lungs. Five. Feel around 
the edge to make sure the facepiece is well seated. 
Correct adjustment and head harness. Six. Re- 
place helmet. Resume the attention. 
Drill "CP To Adjust Respirator from Slung 
Position. 
Being at slung position. (i) Gas. Stop breath- 
ing. Place the rifle, if unslung, between the knees. 
Pull the satchel around until it hangs in front of 
the body. Unfasten the flap and adjust the respira- 
tor as in practice "B," allowing the satchel to hang 
by the rubber tube. Replace helmet, and at once 
proceed to adjust the satchel in the "alert" posi- 
tion, as in practice "A." 
Drill "D." Drill to teach method of testing for 
presence of gas. 
Respirator being adjusted, (i) Test for Gas. 
Take a deep breath. With the right hand pull the 
facepiece slightly away from the right cheek, hold 
the breath, and sniff gently. If gas is smelled, re- 
adjust the facepiece, grip the outlet valve between 
the fingers and thumb, and breathe out hard. 
Drill "E." To remove the facepiece. 
Having tested and found no gas. (i) Remove. 
(2) Face piece. Insert the first two fingers of the 
right hand under the facepiece of the chin, placing 
the thumb on the metal guard of the exit valve, 
bend the head forward, at the same time removing 
the facepiece with an upward motion of the right 
hand. GAS WARFARE 
191 
Drill "FT Inspection. 
The respirator being at slung position. (I) Pre- 
pare for Inspection of Respirators. Place the rifle 
between the knees. Slip the left arm back through 
the sling and bring the satchel around to the front 
of the body. Open the flap of the satchel. (2) 
Inspection. (3) Respirators. Examine the satchel 
and sling, make sure that metal hook and clasp and 
metal loops at each side are securely fastened. Re- 
move canister and hold under left arm, the tube 
and facepiece hanging over the arm. Examine the 
interior of satchel to see that wire platform and 
anti-dimming are there, and that whipcord is in good 
condition and free from knots. Two. Examine 
inlet valve at bottom of canister. Examine the 
canister for rust spots and weak places by pressing 
lightly with the fingers beginning at bottom and 
working to the top. Watch carefully for holes in 
soldering at top of canister. See that the flexible 
tube is properly fastened to the canister, and to the 
metal elbow tube and is free from obvious defects. 
Three. See that the metal elbow tube is securely 
connected to facepiece and that outlet valve guard 
is not loose. Make sure that the outlet valve is in 
good condition, has no dirt or sand in it, has no 
tears, and is connected properly to elbow tube. Four, 
Examine the facepiece inside and out. See that 
chin rest is secure, that there are no pinholes or 
tears in fabric, that air passage to eyepieces is 
in proper condition and not tom away from fabric, 
that eyepieces are securely fastened in the face- 
piece. Examine the head harness and make sure 
that it is firmly attached to binding. Five. Adjust 
mask to face to test valves. Hold canister in left 192 
GAS WARFARE 
hand. Grasp outlet valve between fingers to pre- 
vent passage of air through it, and breathe gently 
in and out a few times. The inlet valve, if work- 
ing properly, should vibrate back and forth. Test 
the outlet valve by putting a kink in the breathing 
tube to prevent the passage through it of air and 
attempt to draw air into the facepiece. If the out- 
let valve is in proper condition, it will not be pos- 
sible to draw in any air. Remove respirators. 
Six. All men having defective respirators step 
forward one pace. All others replace the canister 
in the satchel, taking care not to twist the face- 
piece into wrong position, and return the respi- 
rators to slung position. Respirators should be in- 
spected daily in the alert zone, and at least twice 
weekly in the danger zone. They must always be 
inspected before proceeding into the alert zone. It 
is the duty of all officers and non-commissioned 
officers and their assistants, to make sure that these 
inspections are carefully carried out. A respirator 
must always give complete and absolute protection. 
Its condition can only be determined by constant 
and careful inspection. 
After all drills the eyepieces should be rubbed 
with anti-dimming, leaving a thin transparent film 
of the composition on the glass and the facepiece 
should be wiped dry, folded correctly and put away 
in such a manner that the rubber outlet valve is not 
bent. 
The anti-dimming outfit is carried in the satchel, 
and contains a stick of composition and a piece of 
soft rag. Occasionally at inspection and always 
after each wearing of the respirator, the inner sur- 
faces of the eyepieces should be cleaned and dried. GAS WARFARE 
193 
a little of the composition rubbed on with the finger, 
and the surface rubbed with a soft rag until the 
film of composition is smooth and thin and nearly 
clear. 
Horse Respirator.-In choosing locations for 
stables and horselines if within shell range, high, 
sloping, treeless ground is preferable as less likely 
to hold gas. Horses should not be allowed to stand 
on or be ridden over areas that have been heavily 
shelled by mustard gas, as the skin of the horse 
is more sensitive than that of man to the effects of 
this gas. They should not be allowed to eat grass 
that has been contaminated with mustard gas, or 
drink from infected shell holes. Horses exposed to 
mustard gas should be washed all over as soon as 
possible with soap and warm water, especially 
around the mouth, anus, and sexual organs. Horses 
must be practiced in wearing the respirator, as they 
will otherwise resist protection, and cause delay and 
annoyance in emergencies. 
The horse respirator consists of a flannelette bag 
with a canvas mouthpiece which goes into the 
horse's mouth and saves the flannelette from being 
bitten through. The bag is provided with an elastic 
band which passes round the opening so as to draw 
the respirator close to the face when in use. The 
upper side of the mouth of the flannelette bag is 
furnished with a small unbleached calico patch by 
which the respirator is attached to the nose-band of 
the bridle or halter when in the "Alert" position, 
and while in use. Inside the bag and attached to 
the canvas mouthpiece there is a canvas frame which 
is stitched on to the bag in such a way as to pre- 
vent the material drawing into the nostrils when 194 
GAS WARFARE 
the respirator is in use. The whole is folded and 
carried in a canvas case provided with a flap, se- 
cured by three press buttons, and having two straps 
at the back by means of which the case is attached 
to the bridle or halter. 
Horses can stand a higher concentration of gas 
than human beings without serious injury, and it is 
not, therefore, necessary to protect them against 
cloud gas attacks when they are a considerable dis- 
tance back from the trenches. Nor is it usually 
necessary to protect their eyes. The respirator is 
primarily intended for use on transport animals 
when they are sent to the vicinity of the trenches 
with supplies and ammunition. In the case of gas 
shell attacks, horses should be protected wherever 
the shelling is heavy. 
When not required for immediate use the respira- 
tor can be conveniently carried on the supporting 
strap of the breast harness, or if a zinc wither pad 
is worn, still more conveniently inside this pad. 
If a collar is used in place of the breast-strap, it can 
be carried in the channel of the collar where drivers 
often carry a sponge. However carried, the case is 
steadied by being strapped on either side to the 
metal ring on the supporting strap, and its flap 
should be passed under this strap, between it and 
the wither pad, and buttoned as in the "Alert" 
position. 
When horses are being sent up to the trenches, 
the transport or other officer responsible should 
have the respirators adjusted in the "Alert" posi- 
tion before moving off, as follows: (a) The flap 
of the respirator case is unbuttoned and slipped 
under the nose-band of the bridle or halter from GAS WARFARE 
195 
below upwards, (b) The two straps at the back are 
also passed under the nose-band and secured to the 
check pieces of the bridle, on each side, (c) The 
small unbleached calico patch on the upper side of 
the mouth of the respirator is buttoned on to the 
nose-band of the head collar so that the respirator 
is ready to be slipped on immediately in the event 
of a gas attack, (d) The cover of the case is then 
closed over the nose-band, and the respirator is thus 
protected from rain, and held in position on the 
nose-band. 
The respirator being carried in the "Alert" posi- 
tion is adjusted for use as follows: (a) The flap 
of the case is unbuttoned and the respirator re- 
moved, leaving the case attached to the cheek pieces 
of the bridle and lying flat on the face, (b) The 
mouth of the bag is drawn down over the upper 
lip and upper teeth with one hand on each side of 
the mouthpiece, slipped into the mouth, and drawn 
well up to the angle of the lips, (c) The elastic 
band is seized on either side close to the mouthpiece, 
and pulled outwards so as to draw the mouth of the 
bag tight around the upper jaw, above the nostrils, 
and is then slipped over the poll. 
The respirator is now in position and the animal 
may be worked in it without difficulty or undue dis- 
tress. The bit and reins are not interfered with 
in any way. 
A double feed bag filled with straw, moss or 
leaves saturated with sodium bicarbonate solution 
will make a fair emergency mask. APPENDICES APPENDIX 1 
WARFARE GASES 
In gas warfare gas is used for four purposes:-(i) 
When it is desired to produce deaths or minor casualties 
in front line and supporting trenches prior to an advance. 
(2) When it is desired to produce casualties in front line 
trenches, among supports, reserves and other personnel 
at places where an attack is expected to be made within 
a few hours. (3) When it is desired to produce casual- 
ties in front line trenches among supports and reserves 
and along lines of communications, in concentration 
camps, rest areas, etc., to the limit of range of artillery, 
when no attack is planned or when it will not take place 
for several days. (4) When it is desired to reach train- 
ing areas, cantonments, junctions and places beyond the 
range of guns and which can be reached only by airplanes 
or balloons. 
For technical uses gases are generally divided into 
three groups: 
Persistent. Mustard gas (dichlorethyl sulphide) is the 
leader of this group and is in a class by itself, due to its 
excessive persistency, its effectiveness in low concentra- 
tions and the fact that it affects the skin, eyes, throat and 
lungs, as well as the digestive tract if food exposed to it 
has been eaten. 
Non-Persistent. These gases are highly lethal and 
deadly with low persistency. The group includes phos- 
gene, cyanogen chloride, diphosgene, chlorine and others 
of a similar nature. Chlorpicrin is in this class, although 
it is much more persistent than any of the others. 
Lachrymatory and Irritating Gases. These include bro- 
macetone, ethyl iodoacetate, brombenzylcyanide, and some 
other lachrymators, and diphenyl chlorarsine, or sneez- 
199 200 
APPENDICES 
ing gas. All these gases are highly irritating or lachry- 
matory, but are not lethal, except in very high concentra- 
tions not often attained in the field. Lachrymators are 
economical in forcing the use of the mask and are em- 
ployed for that purpose. 
Mustard gas was discovered by Victor Mayer, a Ger- 
man chemist, in 1886. It is a yellowish oily fluid, freez- 
ing at about 500 F., and boiling at about 4220 F. Its 
color varies with the solvents and impurities in it. It 
combines to a certain extent with the steel or iron in 
shells. It is very highly persistent, that sprayed on the 
ground being very dangerous for a week or longer in 
damp, cold weather. It vaporizes very slowly. It has 
the quality of cumulative effect to a marked degree, be- 
ing at least 50 per cent, for very low concentrations. If 
one part in 2,000,000 is breathed for 20 hours it will pro- 
duce a casualty as serious as one part in 100,000 will 
produce in two hours. It produces casualties almost en- 
tirely by burning, the theory being that the gas in the 
presence of moisture is broken up so as to liberate hydro- 
chloric acid which produces the burn, and destroys any 
soft moist tissue it reaches, whether within or without 
the body. It readily penetrates clothing. The odor of 
mustard gas is not unpleasant, that of the Germans being 
somewhat like mustard while that of the Allies was more 
like garlic. See Chapter IX and Appendix 6. 
Phosgene or carbonyl chloride is a liquid boiling at 470 
F., with a marked odor, like that of moldy hay. Be- 
cause of its low boiling point, it will not remain on any 
terrain on which it is thrown for more than a few min- 
utes. It will form clouds of varying concentration, de- 
pending on the manner in which it is thrown over, and 
a very heavy cloud may render positions dangerous 10 
km. from the original point of attack. 
Phosgene is sent over by the enemy in cylinders, pro- 
jector bombs and trench mortar shells. In cylinders it is 
usually mixed with chlorine in order to form a mixed 
gas of high vapor pressure. It is generally used pure in 
the 75, 170 and 250 mm. trench mortar shells and in the 
180 mm. smooth-bore projector bombs. In these it is 
rarely mixed with chlorpicrin. Recently phosgene has 
been used in long range rifled projector shells mixed appendices 
201 
with pumice, absorption in which retards its evaporation, 
making it persist for several hours. Finally, it occurs 
generally in small proportion as a decomposition product 
of diphosgene in artillery shell for 77 and 100 mm. guns 
and in the 105, 150 and 210 mm. howitzers. 
Phosgene is a lung irritant and is probably the most 
deadly gas used in warfare. Exposure 4o high concen- 
trations for even a short time will cause severe casualties, 
or death, and much lower concentrations will also have 
serious effects. Its full effect is usually delayed for sev- 
eral hours and exercise after exposure to this gas will 
render slight casualties much more serious or even fatal. 
Because of this effect, men who have been gassed even 
slightly and who have experienced no symptoms of gas 
poisoning must be prevented from taking any exercise 
whatever, if serious casualties are to be prevented. 
Phosgene is used entirely as a surprise gas, as high 
concentrations can be developed with it very rapidly. Its 
persistency is low, and it is, therefore, possible to follow 
up a phosgene attack with an infantry advance after a 
very short time. The respirator gives absolute protection 
against this gas. Troops must be trained to put on the 
respirator quickly and well, under any circumstances, and 
sentries must be thoroughly instructed so as to be able to 
recognize phosgene attacks and to give the alarm imme- 
diately. Trenches and dugouts can be quickly rid of 
phosgene by means of fanning and fires. 
Diphosgene, superpalite or trichlormethyl chlorformate, 
is a liquid boiling at 261° F. Its other properties and 
action resemble those of phosgene very closely. It can- 
not be used in cloud or projector attacks because of its 
high boiling point. It is used mixed with chlorpicrin in 
green cross 1 shell of different calibers and with diphe- 
nylchlorarsine in green cross 2. Phosgene usually accom- 
panies diphosgene in the latter, due doubtless to the de- 
composition of the diphosgene. 
Chlorpicrin is a colorless liquid boiling at 2340 F. and 
hence is fairly persistent. It approaches phosgene in its 
poisonous effect. Even in very low concentrations it will 
cause lachrymation and in higher concentrations vom- 
iting, which may necessitate the removal of the mask. 
The clothes of men who have been exposed to chlorpicrin MARKINGS FOR CHEMICAL SHELL AND 
French 
Num- 
ber 
Shell Filling 
American 
and 
British 
Code 
Symbols 
French 
Designation 
German 
Designation 
and 
Shell 
Marking 
Odor 
4 
4B 
Chlorine (Used only in 
cloud gas) 
Arsenic Trichloride 30% 
Stannic Chloride 15% 
Hydrogen Cyanide 50% 
Chloroform _ 5% 
Cyanogen Chloride 70% 
Arsenic Trichloride 30% 
Diphenyl Chlorarsine 
Red Star 
D. A. 
Bertholite 
Vincennite 
Vitrite 
Sternite 
Blue Cross 
Chloride 
of Lime 
Slight 
5 
Diphenyl Cyanarsine 
Phosgene 
D. C. 
C. G. 
Sternite 
Collongite 
Blue Cross 
Three White 
bands. White 
D. 
Is interchan 
Musty Hay, 
Green Corn 
Diphosgene 
Phenyl Carbylamine 
Chloride 
Phosgene, Diphosgene 
and Diphenyl Chlorarsine 
Chlorpicrin 75% 
Phosgene 25% 
Diphosgene and Chlor- 
picrin 
Not used 
S.F. 
P.G. 
Superpalite 
Green Cross 
Green Cross 
Green Cross 
2 
Green Cross 
1 
Disagree- 
able, suffo- 
cating. 
Musty Hay 
Resembles 
Diphosgene 
a little 
pungent 
Pungent, 
Suffocat- 
ing. 
Pungent, 
Suffocat- 
ing. 
7 
Chlorpicrin 
P. S. 
Aquinite 
Pungent 
Chlorpicrin 80% 
Stannic Cholride 20% 
Ethyl Dichlorarsine and 
Dichlormethylether 
IN. C. 
Yellow Cross 
1 or 
Green Cross 
3 
Pungent 
Ethereal, 
Pleasant. 
9 
Bromacetone 
Brom Ketones 
B.A. 
Martonite 
Green Cross 
Pungent 
21 
Brombenzylcyanide 
C. A. 
Camite 
No Odor 
20 
Mustard Gas (Dichlor- 
ethyl Sulphide) 
H. S. 
Yperite 
Yellow Cross 
Slight 
Mustard or 
Garlic 
202 PROPERTIES OF COMMONEST GASES 
Persistency 
Physiological Effect 
In Open 
In Woods 
Remarks 
Non-Persistent Class 
10 min. 
10 min. 
10 min. 
10 min. 
geable wit 
10 min. 
3 hrs. 
3 hrs. 
3 hrs. 
3 hrs. 
hDA. 
3 hrs. 
Lung Irritant, Deadly. 
Action Immediate. 
Lachrymatory and Respiratory 
Irritant. Considered quite 
toxic, but in high concentra- 
tions only. 
A Lachrymator, Respiratory 
Irritant and Lethal Agent. 
Sneezing Gas. Nerve Depres- 
sant. Respiratory Irritant. 
Effects somewhat greater. 
Respiratory _ Irritant. Very 
deadly. Action usually slightly 
delayed. 
These gases are very volatile; they 
are vaporized entirely at the mo- 
ment of explosion, forming a cloud 
capable of giving deadly effects, but 
which loses more or less rapidly its 
effectiveness by dilution and dis- 
persion into the atmosphere. 
These gases form non-persistent 
clouds of solid particles. 
Semi-Persistent Class. 
S hrs. 
3 hrs. 
3 hrs. 
3 hrs. 
3 hrs. 
3 hrs. 
3 hrs. 
3 hrs. 
12 hrs. 
12 hrs. 
12 hrs. 
12 hrs. 
12 hrs. 
12 hrs. 
12 hrs. 
12 hrs. 
Same as phosgene. 
Eye, Nose and Throat Irritant. 
Not very poisonous. 
Respiratory Irritant. Slightly 
delayed action. Very deadly. 
Causes vomiting and a little 
lachrymation. 
Causes vomiting, Respiratory 
Irritant, a little lachrymation. 
Slightly delayed action, very 
deadly, respiratory irritant, 
causes vomiting and a little 
lachrymation. 
Causes vomiting, respiratory 
irritant, tear producer. 
Respiratory irritant, causes 
vomiting, tear producer. 
Nerve poison similar to di- 
phenylchlorarsine, easily de- 
stroyed by water. 
These gases, having moderately high 
boiling points, are only partially 
vaporized at the moment of explo- 
sion. The cloud formed upon explo- 
sion is generally not deadly, but it 
immediately gives penetrative lacry- 
matory or irritant effects. The ma- 
jority of the "gas" contents of the 
shell is pulverized and projected in 
the form of a spray or fog which 
slowly settles on the ground and con- 
tinues to give off vapors which pro- 
long the action of the initial cloud. 
Phosgene in these mixtures has 
same effect as used above, if concen- 
tration is sufficiently high. 
Persistent Class. 
2 days 
3 days 
3 days 
3 days 
7 days 
7 days 
7 days 
7 days 
Lachrymator, Tear Producer. 
Tear Producers, Slight Respir- 
atory Irritants. Action imme- 
diate. 
Not toxic but most powerful 
lachrymator known. 
Respiratory Irritant. Eye and 
Skin Irritant. Blistering Agent. 
Action delayed several hours. 
These gases, having very high boil- 
ing points, are but little vaporized at 
the moment of explosion. A small 
portion of the contents of the shell is 
atomized and gives immediate effect, 
but by far the greater part is pro- 
jected on the ground in the form of 
droplets which slowly vaporize and 
continue the action of the initial 
cloud. 
203 204 
APPENDICES 
are dangerous because of the gas which is carried on 
them and the same precautions against gassing men in 
dugouts must be taken as in the case of mustard gas. 
Chlorpicrin is used mixed with diphosgene in green cross 
I shell. The respirator gives full protection. 
Diphenylchlorarsine is a solid of extremely low vola- 
tility and is practically odorless. It is used in green cross 
2 and in the blue cross shell which contains in addition 
a large amount of high explosive. On the explosion a 
cloud of vapor is formed. The cloud will cause headache 
and intense pain in the throat and chest, accompanied by 
sneezing and coughing. Vomiting and even temporary 
paralysis of the nervous system may finally result. It is 
used mainly to unnerve a man and prevent him from ad- 
justing his mask quickly or to prevent his keeping it on 
after it is adjusted. It is used also for direct neutraliza- 
tion through the production of the above painful symp- 
toms. The effects of this gas when used alone dis- 
appear quickly. The respirator gives absolute protection, 
but must be put on immediately. Diphenylcyanarsine is 
similar in its action and rather more effective. It is used 
in blue cross shell. 
Ethyldichlorarsine is a moderately volatile liquid, pres- 
ent in shells whose marking has recently been changed 
from yellow cross I to green cross 3. It is analogous to 
dipenylchlorarsine in physiological action, exerting a 
more destructive effect upon the respirator tract along 
with the nerve poisoning. It is rapidly destroyed by mois- 
ture. 
Brom-ketones and other gases are used as tear-produc- 
ing agents. They are heavy liquids with high boiling 
points and are used usually mixed with deadly gases, in 
all the various forms of projectiles. They are capable 
of producing blinding tears in very low concentrations 
and are particularly effective in forcing men to put on 
their masks. For this reason they are valuable as harass- 
ing gases. They have also a noticeable poisonous effect. 
They are fairly persistent. The respirator gives abso- 
lute protection against them. Chlorpicrin, in addition to 
its toxic properties, is of value as a tear producer. 
Smoke may be used by the enemy, either in the form 
of a cloud or emitted from shell and bombs. It may be APPENDICES 
205 
used with gas or between gas clouds; it may also be 
used alone to distract attention from a real discharge of 
gas, and in general for preventing observation, as for 
instance as a screening barrage, or for blotting out ma- 
chine gun nests. 
In the tables on pages 202 and 203, the persistency is 
dependent to a large extent on temperature, wind ve- 
locity, and the amount of gas liberated, especially in 
woods or other more or less closed places. High temper- 
atures and wind velocities decrease persistency, and low 
temperatures and wind velocities increase it. 
APPENDIX 2 
CARBON MONOXIDE 
Carbon monoxide is not used directly in an attack, but 
causes a large number of deaths. It is formed when car- 
bon burns or when any high explosive explodes in a con- 
fined place, such as the entrance to a trench, mine or 
dugout. The great danger of this gas arises from the 
fact that it is colorless, odorless, and nonirritant, and that 
the onset of symptoms is so insiduous that very often the 
first warning that a man may receive is failure in the 
power of his limbs which will prevent him from retreat- 
ing into safety. Neither the box respirator nor other 
masks give protection against carbon monoxide; protection 
can only be attained by the use of special oxygen breath- 
ing apparatus. At the autopsy, the blood may be red in 
color instead of dark if there is a considerable degree of 
saturation of the hemoglobin with carbon monoxide. If 
the case has continued to breathe for some time after 
reaching an atmosphere free from carbon monoxide, this 
gas will have been partly or entirely displaced from the 
hemoglobin and the blood after death will have its normal 
color. 
The simplest method of detecting the presence of car- 
bon monoxide in blood is to compare the color of a dilute 206 
APPENDICES 
solution of the suspected blood with a similar solution of 
normal blood. Take a drop or two of blood from the fin- 
ger of a normal person and dilute it in a test tube very con- 
siderably with water (a one-half of I per cent solution is a 
convenient strength), so that when examined by trans- 
mitted daylight the color of this solution is a reddish-yel- 
low. Then take a drop or two of the suspected blood 
and dilute it similarly with water, so that the depth of 
color of the solution is the same as that of the solution 
of normal blood when both are viewed by transmitted 
light. On examining the quality of the color it will be 
found that the solution made with the suspected blood, if 
it contains carbon monoxide hemoglobin, is definitely 
pinker than that made with the normal blood, though it 
will not have the full pink tint of the same normal blood 
solution if the latter be shaken with coal gas so as to 
saturate it quite completely with carbon monoxide. The 
lungs show no abnormal changes in cases of rapid death. 
Small punctate hemorrhages may be found in the white 
matter of the brain and sometimes ecchymoses in the 
meninges if the case has been exposed to a concentration 
of carbon monoxide sufficient to cause prolonged uncon- 
sciousness. 
Except with very massive doses, when loss of con- 
sciousness is very rapid, the symptoms develop very grad- 
ually, as the gas is only absorbed slowly. If a man is at 
rest in a concentration of the gas of i part in 1,000 it 
will take about two hours before definite giddiness ap- 
pears and he will not be definitely disabled until the lapse 
of two and one-half hours. The rate of absorption of 
the gas is much quickened when the breathing is deep- 
ened during muscular exercise and the exercise also leads 
to great accentuation of the symptoms. With a concen- 
tration of 2 parts in 1,000 a man will be seriously affected 
in half an hour if he is performing a moderate amount 
of muscular work, and this concentration may prove fa- 
tal with prolonged exposure. 
Small animals are far more quickly affected by carbon 
monoxide than man is, owing to the natural great ventila- 
tion of their lungs and the rapidity of their circulation. 
A mouse or a canary will show definite symptoms of car- 
bon monoxide poisoning in a tenth of the time that a APPENDICES 
207 
man will. If small animals are used to give an index of 
the presence of carbon monoxide in a suspected atmos- 
phere, it must be remembered that though they show 
symptoms long before a man feels any effects, the man 
will in the end be reduced to the same conditions as the 
animal, and he ought therefore to leave the dangerous 
atmosphere directly the animal shows signs of being 
affected, unless he is protected by special apparatus. 
The first sign that tells a man that something is amiss 
is very frequently a feeling of loss of power in the limbs. 
Giddiness, slight confusion of mind, and breathlessness 
and palpitation on the least exertion also show them- 
selves. The confusion of mind and loss of power in the 
legs frequently preclude a man from withdrawing from 
danger, even though he is dimly aware that safety is only 
a few yards distant. The failure of power in the limbs 
and mental confusion rapidly increase and the man may 
appear drunk, shouting incoherently, laughing, swearing, 
or praying. Apathy and complete helplessness supervene, 
and failure of the intellectual powers gradually passes 
into complete unconsciousness, which may finally termi- 
nate in a painless death. The symptoms may remain sta- 
tionary at any stage, since the degree of saturation of 
the hemoglobin with carbon monoxide reaches a final end 
point which is determined by the relative concentrations 
of the carbon monoxide and the oxygen which are simul- 
taneously trying to combine with the hemoglobin. 
The symptoms detailed above are due to the gradual 
diminution of the oxygen-carrying power of the blood 
and the exposure of all the organs of the body to increas- 
ing want of oxygen. It is clear that any increase in the 
oxygen demands of the body is to be avoided, and any 
man, therefore, who shows definite signs of gassing should 
be carried to a place of safety. If he attempts to walk 
himself he is quite likely to fall down unconscious. When 
a moderately gassed case reaches fresh air he sometimes 
falls unconscious, while other cases may commence to 
shout and struggle, in which case their movements need 
to be controlled. Any case showing definite symptoms 
should be removed as soon as possible to some place of 
safety where he can remain at rest for an hour or two 
before evacuation. Rest is essential. 208 
APPENDICES 
As carbon, monoxide hemoglobin is a dissociable com- 
pound, the carbon monoxide is gradually driven out of 
its combination with hemoglobin by the oxygen of the 
air as soon as an atmosphere free from carbon monoxide 
is reached. In fresh air it will take an hour or two before 
the blood is entirely freed from carbon monoxide, but 
the process can be rendered five times as rapid by giving 
the patient pure oxygen to breathe. It is important there- 
fore to begin the administration of oxygen by some effi- 
cient method as soon as possible after the case has been 
removed from the poisonous atmosphere. Administration 
of oxygen should be kept up as continuously as possible 
for half an hour to an hour, depending on the severity of 
the symptoms. It should be remembered that if a case 
can be kept at rest for half an hour and oxygen ad- 
ministered immediately after being removed from the poi- 
sonous atmosphere, he will be in far better condition to 
travel than if he has to be removed to a more distant 
point. 'If the breathing is very shallow, administration 
of oxygen may be combined with artificial respiration. 
Collapse should be combated by external warmth and by 
friction of the limbs. 
In chlorine poisoning the pulmonary edema and dam- 
age to the lungs and the consequent interference with the 
gaseous exchange taking place between the blood and the 
air in the lungs persist for some time and may necessitate 
the administration of oxygen for several days. In car- 
bon monoxide poisoning the structure of the lungs is not 
interfered with and oxygen is administered with the de- 
liberate intention of accelerating the discharge of carbon 
monoxide from the blood. When once this has been ac- 
complished, i. e., after half an hour's or an hour's admin- 
istration, there is no need to continue the oxygen admin- 
istration, as the oxygen-carrying power of the blood has 
now become normal again. Any symptoms that persist 
are due to effects that were produced while the blood was 
charged with carbon monoxide and are unlikely to be in- 
fluenced by oxygen administration when once the carbon 
monoxide has been got rid of. Further oxygen adminis- 
tration is therefore required only if cyanosis begins to 
develop subsequently from secondary cardiac or respira- 
tory failure. APPENDICES 
209 
Cases of carbon monoxide poisoning have been known 
to recover, even when they have remained unconscious 
for so long as 48 hours after removal from the poisonous 
atmosphere. In cases that have been severely gassed the 
possibility of subsequent cardiac dilatation must not be 
lost sight of, and cases of severe gassing should not be 
returned to duty until confidence is felt that the circula- 
tion has recovered from the strain. As a result of dam- 
age to the nervous system while the blood was charged 
with carbon monoxide, paralysis of single muscles or a 
group of muscles, or different forms of mental disturb- 
ance are sometimes found as sequelae. 
APPENDIX 3 
CHLORINE 
The effects of chlorine poisoning may be classified un- 
der the headings of irritation and inflammation of the 
respiratory tract, interference with the circulation and 
general toxic effects. The irritation of the sensory 
nerves, however, is not the fatal factor. An inflamma- 
tory reaction, with congestion of the vessels, edema of 
the tissues and an abundant discharge of serous effusion 
through the dying epithelium occurs all the way down the 
respiratory tract. This begins at the back of the throat; 
the larynx, with its resistant epithelium, escapes injury,, 
but the damage to the surface tissues increases progres- 
sively down the trachea, the bronchi and their finer 
branchings, and ultimately attains its maximum in the air 
sacs. The bronchioles are rapidly filled with a serous 
exudate which passes up into the trachea and is coughed 
out. 
A universal obstruction in this way of the bronchioles 
alone would suffice to cause death by simple blockage of 
the airway and asphyxia. But the injury is not confined 
to the bronchial tree and probably the effusion in the 
tubes alone is not dense enough to hinder the passage of 210 
APPENDICES 
some air up and down, though even this thin fluid may 
constitute a very serious mechanical obstruction when 
it is churned up into a continuous foam by violent res- 
piratory efforts. At first there may be so much spas- 
modic contraction of the muscles of the smaller bron- 
chioles that the gas is denied access to many areas of the 
lungs. Sooner or later these relax, and the irritant vapors 
then destroy the pulmonary epithelium, while the air sacs 
rapidly fill up with inflammatory exudate and become ut- 
terly useless for the purpose of respiratory exchange. 
The edematous effusion must ultimately compress the 
capillaries and cause great hindrance to the flow of blood 
through the lungs. The irritation spreads so widely that a 
blood-stained serous effusion soon accumulates in the 
pleural cavity, but this is never so abundant as to require 
aspiration. 
In addition to this inflammatory edema, which chokes 
the circulation and prevents gaseous exchange, there is 
often some actual damage to the structure of the lungs. 
The violent coughing and inspiratory efforts which may 
result from inhalation of the gas may be so forcible that 
the partitions between the alveoli are torn and air may 
even burst its way out into the areolar tissue and escape 
along the hilum of the lung and up into the subcutaneous 
tissues of the neck. Such disruptive emphysema adds at 
once to the disability of the sufferer, since it throws out 
of action that part of the lung which is not yet submerged 
in the rising flood of edema fluid, and it may lead to per- 
manent shortness of breath if the man survives. 
There are four factors which develop in rapid succes- 
sion and prevent exchange of respiratory gases through 
the lungs: (i) Narrowing of the bronchioles by spas- 
modic contraction of muscles in their walls. (2) Dis- 
ruptive emphysema. (3) Obstruction of the bronchial 
tubes by exudate. (4) Flooding of the pulmonary air 
sacs by serous effusion into them. The result of these 
changes in the lungs, of which (3) and (4) are the most 
important, is that the intake of oxygen and the elimina- 
tion of carbon dioxide are seriously interfered with, and 
the man passes into a state of asphyxial cyanosis in which 
mental failure and unconsciousness may rapidly super- 
vene. During this state the breathing is labored, rapid, APPENDICES 
211 
and interrupted by spasmodic bouts of coughing. The 
blue color of the face shows the urgent need for oxygen, 
and every muscular effort made by the body and by the 
heart increases that need. Coughing is helpful in so far 
as it may dislodge exudate from the bronchi, but the vio- 
lent effort is prodigal of such oxygen as can be supplied 
and it tends to increase the disruptive emphysema. The 
increased respiration is caused both by the accumulation 
of carbon dioxide and by the want of oxygen and not by 
the absorption of any poisonous substance from the gas. 
In itself, this increased breathing does no harm and it 
helps in eliminating COa and increasing the intake of 
oxygen which are the chief needs of the moment. 
The ordinary phenomena in asphyxia of mechanical 
origin are that the blood pressure rises and that the 
heart soon loses its full driving power because its muscle 
cannot maintain this increased effort when it is working 
with a scanty supply of oxygen. Consequently the pulse 
rate quickens, the right heart dilates and the blood tends 
to be pooled up behind it in the great veins. If this fail- 
ure proceeds apace, a patient who at the beginning 
showed congestive cyanosis of the face with a full pulse 
will gradually assume a gray pallor while the pulse accel- 
erates and falls off in power. These changes are present 
in cloud gas poisoning and they are augmented by the 
edema of the lungs, which directly obstructs the pulmo- 
nary circulation and causes an earlier failure of the right 
side of the heart. If the patient during this critical time 
tries to carry on his work and remain standing, he will 
use up still more rapidly the little oxygen that he is re- 
ceiving, extra work will be loaded on to a heart which is 
already overstrained and the circulation will be likely 
to fail still more speedily on account of the difficulty of 
maintaining compensation in the upright posture. There 
is no interference with the respiratory properties of the 
blood which can at once take up any oxygen that reaches 
it through the lungs. 
Experiments indicate that chlorine is not absorbed from 
the lungs and that the effects produced by this gas are 
only a direct and local inflammation with secondary re- 
sults which are either of a mechanical nature or caused 212 
APPENDICES 
by oxygen want or due to a nervous reflex from the 
scat of injury. Changes of a general nature do undenia- 
bly appear in the nervous, circulatory, alimentary, and 
renal systems of a man who has been poisoned by cloud 
gas, but these are probably the result of the asphyxia 
rather than of the direct action of the gas. Thus in the 
mild cases there is a sense of fatigue and of being alto- 
gether done up, and in the serious cases even uncon- 
sciousness, but these features are not in excess of what 
may result from oxygen want. The retching and vomit- 
ing that generally occur in the first stages of poisoning 
may be due only to direct irritation of the back of the 
throat and of the stomach by the gas, or may be the direct 
sequence of violent bouts of coughing, while the diarrhea, 
which sometimes is an early feature, may be that of 
emotion. 
Microscopic examination of the kidneys in death, a few 
days after gassing, reveals very definite inflammatory and 
destructive changes, and such kidneys may be swollen 
and enlarged as though with a parenchymatous nephritis. 
This change, however produced, rarely leads to any clini- 
cal feature of renal trouble. In the first few days the 
urine contains neither sugar nor albumen nor many casts, 
and it is very unusual for albuminuria to develop later. 
The circulation may fail with unexpected rapidity and 
the patient soon present the aspect of a leaden gray cya- 
nosis. But in general terms the clinical picture with 
chlorine may be summed up as that of a man suffering 
from intense irritation of the respiratory tract and dying 
by asphyxia from the fluid that has drowned his lungs. 
It does not suggest a deeper toxic action. 
In a case of death at 24 hours after gassing, the tra- 
chea and bronchi are purple red and congested, while a 
thin serous exudate wells up into them from the lungs. The 
latter organs are heavy and edematous, while aerated 
islets of emphysematous overdistention alternate with de- 
pressed purple patches of collapse. On section, serous 
fluid drips abundantly from the lung tissue. Air that 
has escaped from ruptured vesicles is seen in chains of 
bubbles on the surface of the lungs, along the interlobar 
fissure and even penetrating the tissues of the mediasti- APPENDICES 
213 
num. In some of the earliest cases the most intense dis- 
ruptive emphysema was observed, destroying the air sacs 
and interfering with the circulation in their walls. 
Petechial hemorrhages appear on the surface of the 
lungs, on the heart, and also on the inner surface of the 
stomach. All the veins are greatly distended and the 
abdominal viscera are engorged with dark blood that 
clots very early after death. The heart itself may fail 
to show right-sided dilatation, for this does not of neces- 
sity appear post mortem in cases of asphyxial death. 
If the man succumbs at a later date, inflammatory com- 
plications appear on the lungs. There is superficial pleu- 
risy, scattered broncho-pneumonia, and a purulent se- 
cretion in the bronchi. The serous exudate will then be 
found to have disappeared and no fluid drips from the cut 
surface of the lungs. 
APPENDIX 4 
PHOSGENE AND LETHAL GASES 
The symptoms of phosgene, chlorpicrin, cyanogen, 
chloride, diphosgene and other highly lethal gases with 
low persistency differ from those produced by chlorine in 
the three following details: 
(i) Subjective respiratory irritation is much less in 
evidence. The men do not suffer with such violent 
coughing when first exposed to the gas. There is conse- 
quently less disruptive emphysema of the lungs, and sub- 
cutaneous emphysema of the neck is rare, while post- 
mortem examination in early cases often fails to find 
anything more than a little escape of air along the inter- 
lobar fissure. 
(2) The poisonous effects may appear speedily with 
cyanotic asphyxia, but sometimes they are more insidious 
in their onset. A man may feel able to carry on his work 
for an hour or two with only trivial symptoms; then he 
rapidly becomes worse and passes into a state of grayish APPENDICES 
214 
white collapse, with progressive edema of the lungs that 
may soon be fatal. It has even been reported from the 
trenches that men who have passed through a gas attack 
and seemed to have suffered but slightly have died abrupt- 
ly some hours later upon attempting some bodily effort. 
(3) Features suggestive of general collapse are more 
in evidence. There is a much greater tendency to circu- 
latory failure. Many of the cases that die on the first day 
show a leaden gray tint of the face rather than a purple 
red cyanosis; the pulse is rapid and of poor tension. 
Mental confusion or mild delirium with restlessness and 
unconsciousness become more prominent in the severe 
cases. No case has been reported of death immediately 
upon exposure to the gas, although men have gone 
through an attack of gas in high concentration without 
wearing a mask at all and succumbed in consequence an 
hour or more later. 
The action of phosgene (COCL) differs from that of 
chlorine in certain respects. Upon meeting moist sur- 
faces it is broken up and hydrochloric acid is liberated. 
It excites less spasm than does chlorine in the upper res- 
piratory tract, and so can penetrate to the innermost 
recesses of the lungs, where it causes an irritant edema 
which may be a little delayed in its development, like that 
caused by the acids formed from nitrous fumes, although 
the delay in the latter case is more prolonged. Experi- 
ments do not show that the products of phosgene are 
absorbed from the lung and act as general poisons apart 
from their local action. 
In a case of death by asphyxia cyanosis where inflam- 
matory effusion had developed with great rapidity the 
lungs were smaller than normal, heavy, uniformly airless 
and purple, so that each resembled a big spleen. There 
was no disruptive emphysema. Thin serous fluid ran 
abundantly from the surface when cut across. Each pleu- 
ral cavity contained about 15 ounces of serous effusion. 
There is no striking difference between the cases which 
had shown pallid collapse and those which succumbed 
in extreme cyanosis. The condition of the heart is found 
to be variable, but there is always evidence in the viscera 
of vascular engorgement from failure of circulation. 
The lungs never show voluminous emphysema, and in- APPENDICES 
215 
deed the earlier the death the greater is the serous edema 
in their substance. On the second day the fluid does not 
drip quite so freely from the cut surface as on the first, 
and toward the beginning of the third day the general 
aeration of the lung is everywhere greater, while relative- 
ly large islets of well-aerated and slightly emphysematous 
lung may be present between areas of edema or collapse. 
This aerated condition appears at first in the lower lobes 
of the lungs where they are in contact with the dia- 
phragm, while edema persists longest and is most profuse 
in the upper lobes. A day later and no serous fluid at 
all escapes from the cut surface. At this date inflamma- 
tory complications tend to appear in a surface pleurisy, 
and areas of the lung are found to be slightly friable and 
entering into a condition of broncho-pneumonia. 
It may be that cases of extensive and overwhelming 
edema succumb at once, while those in which on the sec- 
ond or third day larger islets of aerated lung alternating 
with edematous patches are seen, had from the beginning 
been in that state, so that they succumbed later than the 
completely edematous group because the injury to the 
lung was less. But the general evidence favors a more 
hopeful view, namely, that the edema fluid is rapidly ab- 
sorbed from the second day onward, and that the later 
post mortems illustrate the stage in this recovery. The 
chief fact in support of this view is that patients who 
had been deeply cyanosed at first, with the usual signs 
of extensive pulmonary edema, and so asphyxiated as to 
be unconscious for a couple of days, may yet recover so 
completely that eight or nine days after exposure to gas 
it is difficult to discover any physical signs of edema in 
the lung. 
Upon exposure to chlorine alone, a man feels imme- 
diate respiratory distress. He coughs violently and speech 
is made impossible by his spluttering gasps. With the 
later forms of drift gas, the onset is slightly altered. 
There is some lachrymation. The throat feels gripped 
and the chest tight. Breathing is difficult but not impos- 
sible. Coughing develops a quarter of an hour or more 
later. Nausea and vomiting appear quickly, so that a 
man who was slow in getting protection may vomit in- 
side his gas mask. Headache and throbbing sensations 216 
APPENDICES 
in the body are experienced. Coughing and retching 
increase. The respiration becomes very hurried and la- 
bored, though shallow. The patient's face assumes a cya- 
notic hue; he may lose muscular power and consciousness 
and die in an hour or two. Those who survive longer 
show the following features: 
Headache, pain behind the sternum and in the epigas- 
trium. Extreme restlessness and anxiety, or a semicoma 
with a muttering delirium, from which as a rule they can 
be roused to answer questions. Varying cough, some- 
times slight, sometimes reiterant with a croupous rattling 
from exudate in the trachea. There is practically no 
laryngitis. A cyanotic blueness in the lips and ears, 
which may accompany a flushed lividity of the face or the 
grayish-yellow pallor of collapse. Extremely rapid res- 
piration, from 40 up to even 80 a minute, of a shallow 
type on a distended chest, and often marked by a jerk- 
ing grunt of expiration. A pulse of about 100, which 
may rise to a higher rate and fall to a very low pressure 
in the gray examples of collapse. The skin is dry, and 
either hot or cold in correspondence with the state of col- 
lapse. Expectoration may be very slight, though in oth- 
ers there soon develops an abundant discharge of thin 
watery fluid, often streaked with blood, which simply 
flows from the mouth as the dying patient loses power 
to expel it. After death, the foam from this fluid may 
dry to a white efflorescence around the mouth. The per- 
cussion note is slightly flattened over the lungs behind, 
where the breath sounds are much weakened, but other- 
wise unchanged in quality. Fine rales are heard behind 
and in the axillae. There are no tubular breath sounds. 
In front there may be extremely little change beyond 
harshness in the breath sounds. The physical signs fail 
altogether to indicate the extent to which the lungs are 
damaged, for in any area examined there is always some 
aeration of the bronchioles and alveoli which suffices to 
produce relatively normal sounds on auscultation. 
Four-fifths of the deaths occur in the first 24 hours. 
Very few succumb after the third day. A man, who at 
first seemed to be lightly gassed, may, toward the end of 
the first day, develop cyanosis and die; but from the end 
of the second day onward, there is no danger to be ap- APPENDICES 
217 
prehended for the less grave cases. On the second day 
the sputum becomes less abundant, more viscous and yel- 
low tinted. The dyspnea persists and the temperature is 
raised. If complications develop subsequently from in- 
fections of the raw respiratory tract, they will be shown 
by persistence of fever, by a purulent sputum, and by signs 
of broncho-pneumonic consolidation. 
But as a rule the patient recovers rapidly after the 
third day, and at the end of a week he is fully convales- 
cent. Cough, pain in the chest, which is often very se- 
vere beneath the rib margins, shortness of breath, loss of 
appetite with gastric pain, and general lassitude persist 
longest of the symptoms. There are no serious after re- 
sults to be apprehended. A man who has been badly 
gassed requires a long rest; but the majority, if free from 
neurasthenic symptoms, are fit for light duty in a very 
few weeks, provided that they are allowed sufficient rest 
at first. The heart and circulation are severely strained 
by gas poisoning. Convalescents who show tachycardia 
must be carefully watched lest too heavy physical effort 
earty in the first month of recovery induce further strain 
and lead to the condition of irritable soldier's heart, from 
which recovery will be long delayed. 
In some cases that died after two or three days of per- 
sistent cyanosis and unconsciousness the white matter of 
the brain was found to be peppered with tiny petechial 
hemorrhages. These are the direct outcome of the 
asphyxial state and have little clinical significance. Large 
cerebral hemorrhages have, however, been noted, occur- 
ring on the first or second day in cases of plethoric cya- 
nosis. 
Men, and especially officers, should be warned before- 
hand that if lightly gassed they must refrain from mov- 
ing about or shouting out orders. Physical strain after 
gassing may easily involve the loss of a life that might 
otherwise have been restored to the fighting line in a 
short time. All kit that hinders the play of the respira- 
tory muscles, especially belts and suspenders should be 
undone. Sleep brings improvement, and restless excited 
cases should be quieted by morphia. It is important that 
arrangements should be planned beforehand at each 
casualty clearing station so that even a large number of 218 
APPENDICES 
gas casualties can be handled with such discipline and 
control as will at once introduce a sense of order and 
quietude, and by separating those who are more danger- 
ously ill from the remainder, enable the less severe cases 
to get to sleep at once. 
Next in importance to rest comes the use of oxygen, 
protection from cold, special stimulants or drugs, vene- 
section, and methods for removing serous exudate from 
the lungs. Bronchial spasm does not seem to be a serious 
danger with the present form of cloud gas. Life or death 
is decided by the degree of pulmonary edema and as- 
phyxia with circulatory failure. The edema fluid tends 
to be absorbed quickly, and if the patient can be carried 
alive through the first two days, he should recover. Pre- 
cautions in the meantime need to be taken to lessen the 
chance that secondary respiratory infections may develop 
as a later complication. 
Oxygen, if rightly administered, will generally lessen 
cyanosis, and therefore improve the patient's chance of 
life. But the lung surface available for absorption is so 
small that the oxygen must be given in high concentra- 
tion. The simple admixture with air obtained by open 
flow from a funnel or a tube placed in the patient's mouth 
is useless, and since it wastes valuable oxygen it should 
be forbidden. Given as the pure gas from a bag with a 
valved face mask, say for 3 or 4 minutes every quarter of 
an hour, an oxygen cylinder of 20 feet capacity will last 
about 4 hours. By this means life can undoubtedly be 
saved in some of the apparently desperate cases. The ad- 
ministration must be continued night and day, so as to 
hold cyanosis in check. The consumption of oxygen by 
this method is so large that all care must be taken to 
economize cylinders, the provision of which, under active 
service conditions is necessarily limited by considerations 
of transport. Many casualties are so severely poisoned 
that their condition is seen in the first few hours to be 
hopeless. Some selection of the cases for oxygen treat- 
ment must therefore generally be made, and it is espe- 
cially with the intermediate group who are surviving into 
the second day that oxygen has the best chance of acting 
with ultimate advantage. It is quite unnecessary to use 
it for relatively mild cases. Deep cyanosis, whether of APPENDICES 
219 
the congestive or pallid type, is the indication of need, 
and the lividity can almost always be lessened if the face- 
mask is properly applied. 
APPENDIX 5 
NITROUS FUMES AND LACHRYMATORS 
The great danger of nitrous fumes, nitric oxide and ni- 
trogen peroxide, arises from the fact that in the concen- 
trations usually met with there is comparatively little 
irritation of the eyes or upper respiratory passages, and 
a man working in such an atmosphere will not recog- 
nize its deadly nature. Air which contains enough ni- 
trous fumes to cause feelings of irritation in the nose or 
air passages must be regarded as very dangerous. Ni- 
trous fumes are very soluble in water, and the gas may 
be readily removed from the atmosphere by means of a 
water spray, whilst a few folds of a handkerchief or a 
towel wetted with water and tied over the nose and mouth 
will give efficient protection in the absence of a mask. The 
possibility of the simultaneous occurrence of carbon mon- 
oxide in atmospheres containing nitrous fumes must be 
remembered. 
The pathological changes found post-mortem in a fatal 
case of nitrous fumes poisoning are identical with those 
described as characteristic of chlorine poisoning. If the 
concentration of nitrous fumes to which the case has been 
exposed is very high, the blood may be somewhat choco- 
late colored owing to the formation of methaemoglobin. 
If the gas is in very great concentration, rapid fatal as- 
phyxiation takes place, but in the concentrations that are 
usually encountered, the characteristics which distinguish 
this from chlorine poisoning are the slightness of the in- 
itial symptoms due to irritation of the upper respiratory 
passages and delay in the onset of acute pulmonary ede- 
ma. The typical sequence of events is- 
(i) Slight irritation of the nose and throat, feeling of 220 
APPENDICES 
constriction of the chest, headache and slight smarting 
of the eyes and coughing while actually exposed to the 
fumes. 
(2) On leaving the poisonous atmosphere a latent 
period during which the case may, and usually does, feel 
quite well and has no hesitation in taking a meal. 
(3) The sudden onset after four to eight hours of acute 
symptoms. These commence with marked and increasing 
distress in breathing, coughing, and often severe pain in 
the chest. The cough is at first dry, and auscultation may 
reveal no moist sounds. This condition is speedily fol- 
lowed by the urgent signs of acute pulmonary edema, and 
death may ensue in a few hours. 
When once pulmonary edema has developed, the treat- 
ment should follow the lines laid down for chlorine poi- 
soning. The experience of medical officers attached to 
mines where nitrous fumes are frequently met with dur- 
ing blasting operations, points to the value of inducing 
emesis as soon after exposure to the fumes as possible, 
followed by a dose of such a stimulant as aromatic spirits 
of ammonia. A case of nitrous fumes poisoning should 
be under medical observation at the time when acute pul- 
monary edema is likely to develop and a venesection of 
from 5 to 20 ounces should be made as soon as there 
is the slightest sign of its onset. Venesection must not be 
delayed until the patient's condition is grave and the 
stage of lividity has been reached, or it will be useless. 
The immediate effect of a trace of the vapor of such 
a lachrymator as benzyl bromide in the air is to cause 
profuse watering of the eyes, accompanied by smarting. 
If the concentration is somewhat greater, the smarting 
and pain in the eyes may become intolerable, so that it is 
impossible to keep the eyes open. The smarting and wa- 
tering of the eyes will be quite sufficient to put a man 
completely out of action, because he is incapable of see- 
ing, but protection of the eyes is easily obtained by the 
use of goggles. 
With increasing concentrations of the vapor, other 
effects show themselves. The vapor is irritant to the 
lungs and upper respiratory passages and this leads to a 
burning sensation in the throat and coughing. Nausea is 
often present and not infrequently leads to vomiting, ac- APPENDICES 
221 
companied, it may be, by pain in the epigastrium. If it is 
impossible to withdraw from exposure to the fumes, slight 
confusion of mind and torpor may show themselves. 
Under ordinary conditions the symptoms do not develop 
further, and though the case may become somewhat col- 
lapsed as a result of the vomiting and general discomfort, 
this is only temporary, and within an hour or two after 
getting into air free from the lachrymator there may be 
very little amiss with the man. The nausea and irritation of 
the throat soon pass off, though the eyes may remain sore 
for some little time, and even after the lapse of 12 hours 
redness of the eyelids and slight injection of the conjunc- 
tiva may still be evident. There are no subsequent toxic 
effects and the case will be fit for duty as soon as the 
primary effects have passed off. 
It must not be forgotten that some of the acute lung 
irritants are also extremely powerful lachrymators, and 
that such substances may be used with a view to securing 
a double effect, viz., immediate blinding and simultaneous 
intense toxic effect on the lungs. In order to secure such 
an effect it is essential that the substance used shall be 
gaseous or shall vaporize with sufficient rapidity to at- 
tain a high enough concentration in the air to produce 
these intense tokic effects. Lachrymators such as ben- 
zyl bromide, which are liquid at ordinary temperatures, 
vaporize too slowly to produce such a concentration. The 
smell of benzyl bromide when in great dilution suggests 
the flavor of mustard and cress. Lachrymators as a rule 
have aromatic, pungent odors. 
When in sufficient concentration hydrocyanic acid acts 
as a very rapid and sometimes almost instantaneous poi- 
son, affecting directly the central nervous system. The 
symptoms follow one another in rapid sequence: Giddi- 
ness, confusion, headache, indistinct sight, palpitation and 
pain in the chest and over the heart. Labored respira- 
tion. Unconsciousness, convulsions, failure of the respi- 
ration and finally of the heart. In large doses, immedi- 
ate unconsciousness, dilatation of the pupils, a few gasping 
respirations, and death with or without convulsions. 
The gas paralyzes the respiratory center very quickly, and 
with small fatal percentages the heart may continue to 
beat for a brief time after the respiration has ceased. 222 
APPENDICES 
With larger concentrations the heart may be stopped al- 
most at once by the direct action of the poison. When 
death is caused by inhalation of hydrocyanic-acid gas, it 
is unlikely that the smell of the gas will be detected at 
autopsy, as may be the case when poisoning is due to the 
ingestion by the mouth of a large dose of prussic acid. 
Immediate treatment is the only measure of any avail 
if a man falls unconscious from hydrocyanic-acid poi- 
soning. The case must be at once dragged into fresh 
air, and if the respiration has stopped, or is very weak 
and gasping, artificial respiration must be instantly ap- 
plied by Schafer's method. 
APPENDIX 6 
MUSTARD GAS 
Dichlorethylsulphide, known as mustard gas, Yperite 
or Yellow Cross gas, is an oily liquid boiling at 4220 F. 
On account of its high boiling point, it vaporizes very 
slowly, and is therefore, extremely persistent. It is a sta- 
ble compound, being but slowly destroyed by water at 
ordinary temperatures, more quickly by alkalies such as 
bicarbonate of soda. Chloride of lime will destroy any 
mustard gas, either liquid or gaseous, with which it comes 
in contact. The liquid will soak into soil on which it is 
thrown and remain there from a week to a month. There- 
fore mustard gas shell holes should not be dug up for a 
considerable time after a bombardment. The liquid which 
remains in or above the surface layer of the soil will 
slowly vaporize under the heat of the sun. This vapori- 
zation will not as a rule be great enough at night or dur- 
ing cold weather to produce dangerous concentrations of 
gas, but as soon as the ground is warmed by the sun, 
troops passing near will be in almost as great danger from 
the gas as at the time of the bombardment. Mustard 
gas also has the property of remaining on and penetrat- 
ing woolen and cotton fabrics. Rubber is penetrated APPENDICES 
223 
fairly rapidly. Oiled fabrics delay penetration to a con- 
siderable extent. However, it is unwise to depend on this 
protection for more than a few hours. 
The Germans use mustard gas in shell for 77 mm. gun, 
and for 105 mm., 150 and 214 mm. howitzers, more rarely 
in 100 mm. and 150 mm. guns. The distinguishing mark 
is a yellow cross on the side or base of the shell or both. 
The filling is dichlorethylsulphide, usually mixed with a 
solvent: carbon tetrachloride, chlorbenzene, or nitro-ben- 
zene. These shells have been generally provided with a 
medium bursting charge, although the use of yellow cross 
shell with a high bursting charge, simulating high ex- 
plosive shell, is increasing continually. These latter are 
marked with a yellow Lorraine cross. The charge in the 
Lorraine cross shell is of sufficient size to produce a spray 
of very finely divided particles of the liquid and in this 
form, though less persistent, the gas is more concentrated 
and dangerous. 
The following points should be carefully noted in re- 
gard to this gas, as they, in combination with its per- 
sistence, make it the most dangerous of all. Unlike oth- 
ers, it has very little immediate irritating action on the 
respiratory system or in the eyes, and, therefore, does not 
force a man to put on his respirator. Exposure to either 
liquid or vapor, even in low concentration, will cause 
irritation of any tissue with which it comes in contact. 
This iritation is usually not noticed for from 3 to 12 
hours after the exposure and may affect any part of the 
body. The worst mustard gas cases are due to irritation 
of the respiratory tract, which is often serious enough 
to cause death. A secondary effect is often pneumonia 
or in lighter cases bronchitis and an acute sore throat 
lasting for several weeks. Exposure of the eyes to the 
vapor will cause temporary blindness, which is very pain- 
ful, and will last from a few days to several weeks, de- 
pending on the length of the exposure. The third effect, 
from which mustard gas derives its name of vesicant or 
blistering agent, is the production of painful burns on 
those portions of the skin with which it comes in contact, 
particularly the tender and moist parts under the arms 
and around the scrotum. 
Mustard gas is used rather as a neutralizing than as a 224 
APPENDICES 
surprise gas, because its slow evaporation prevents the 
rapid formation of high concentrations. Its persistency 
is greater than that of any other gas, and hence by its 
use any position may be made untenable for days after it 
is shelled. It is particularly valuable for use against 
valleys and woods, because such terrain will remain in- 
fected longer than open country. It is used in general 
against artillery emplacements, support and reserve posi- 
tions, command posts, billets, woods, communicating 
trenches and roads. The following translation of a cap- 
tured German document is instructive: 
Bombardment with yellow cross shell will be executed 
preferably between one and four A. M. At first the bom- 
bardment will compel the enemy to wear his mask. A 
few hours later, when the presence of the gas is no longer 
revealed by the odor, the enemy will probably take off 
his mask, but will be overcome later, when the sun rises, 
by the action of the evaporation. Every attempt of the 
enemy to nullify the effects of the night gas bombardment 
in the morning should be neutralized by volleys of rifle, 
machine gun, minenwerfer and artillery fire. 
Mustard gas is rarely used during the three or four 
days preceding a large scale "push," except against those 
points over which it is not intended to advance. Particu- 
lar care must be taken in occupying terrain captured from 
the enemy because of the danger from gas traps left dur- 
ing his retreat. Gas shell and bombs may be left in dug- 
outs or farmhouses and fused to explode when the local- 
ity is filled with our troops. Mustard gas may be sprin- 
kled on roads and at all points over which troops must 
pass. All shelters will in general have been liberally 
soaked with mustard gas. 
The respirators in use by the American forces give 
absolute protection against all but the blistering action 
of mustard gas. Certain special precautions in their use 
must be observed. Because of the slight odor and de- 
layed action of mustard gas, troops must be trained to 
put on the respirator immediately when any odor is no- 
ticed which might be that of gas. They must not remove 
the respirator until all traces of the gas have disappeared. 
They must be trained to wear it for long periods of time 
and to be able to work efficiently while wearing it. Men APPENDICES 
225 
who have been exposed to mustard gas and have been 
testing for it for several hours, gradually lose their abil- 
ity to detect it. On wearing the mask a short time one 
recovers his keenness of smell for the gas. 
Sag paste is a protective ointment which, if applied be- 
fore exposure to the gas, will greatly diminish its effects 
upon the skin. The paste should be rubbed liberally in 
an even layer on the genital organs and region, the but- 
tocks, the armpits, and other parts of the body which 
perspire freely. The length of time that such an appli- 
cation is effective depends entirely upon the strength of 
the gas. Since there is no way of judging this easily in 
the field, care must be taken to use a sufficient quantity 
of the paste and to renew the application about once every 
12 hours when continually exposed to the gas. It should 
be carefully noted that sag paste must be applied before 
troops enter an area that is likely to be shelled. This will 
have to be done on the judgment of the unit gas officer. 
Any portion of the skin which has been splashed by 
the liquid from mustard gas shells or even moist parts 
that have been exposed to the vapor should be washed 
as quickly as possible with soap and water. Any kind of 
soap will answer and cold water is satisfactory. It is 
only necessary to work up a good lather and massage the 
place well with this lather. Very little water used in this 
way often suffices to prevent burns. If chloride of lime 
is available, as it should be, some of the dry powder sprin- 
kled on the skin that is splashed with mustard gas liquid 
will prevent a bad burn. The powder is to be left on the 
skin about fifteen minutes and then washed off with 
water and soap if obtainable. 
In general, the best protection against mustard gas is 
evacuation of all ground infected by it, if the tactical, 
situation permits, and alternative positions should be 
prepared or selected in advance. If a zone has been 
evacuated after a mustard gas bombardment, sentries 
should be posted on all roads and paths entering this zone 
to warn troops away from it and to prevent their entering. 
Sentries should also be posted in front of contaminated 
dugouts in a zone otherwise free from mustard gas. If 
not possible to evacuate, frequent reliefs, or protection 
of troops as far as possible in gasproof dugouts will alone 226 
APPENDICES 
prevent numerous casualties, as mustard gas will outlast 
the staying power of troops wearing the respirator. In 
connection with the use of gasproof dugouts, it should 
be noted that men entering such dugouts have gassed the 
occupants by the gas which they have brought in on their 
clothes and, therefore, all outer clothing should be re- 
moved in the entrance to the dugout and soles of shoes 
treated with chloride of lime. A scraper, water, and box 
of chloride of lime should be kept near the entrance to 
each dugout. The shoes are first dipped into the water, 
then thoroughly rubbed in the lime, and finally washed off 
in the water. This precaution, if followed by thorough 
washing of the body, will be very effective in preventing 
burns. It should be noted that the enemy will probably 
not knowingly attack across an area recently shelled with 
mustard gas. 
After a mustard gas bombardment, the covering of 
shell holes with chloride of lime will render such shell 
holes harmless. The chloride of lime should be spaded in 
well, then covered with another thinner layer of lime 
which is in turn covered with fresh earth. This should 
be done by a special disinfecting squad provided with the 
proper protective clothing. It is manifestly impossible 
in the case of an extensive bombardment to disinfect all 
shell holes in this way, but those near which troops pass 
or near dugouts should always be disinfected. Men after 
walking over an area infected with mustard gas will find 
it necessary to destroy the poison on their shoes before 
entering a dugout, as this liquid readily evaporates after- 
wards in the dugout, rendering the atmosphere extremely 
dangerous. Chloride of lime is placed on the ground out- 
side of dugouts, in order that the men may use the lime 
to destroy the liquid that may be carried upon their 
shoes. There is an element of danger in the use of chlo- 
ride of lime to destroy gas due to the fact that the 
odor of the former completely masks that of the latter. 
When chloride of lime is thrown on liquid mustard gas, 
some chlorine is given off. This will cause little annoy- 
ance. However, the heat of the reaction may vaporize 
some of the mustard gas which has not yet been de- 
stroyed. When large puddles of the liquid are encoun- 
tered, they will first be sprinkled with sand, dry earth or APPENDICES 
227 
ashes, to absorb the greater part of the poison before be- 
ing treated with chloride of lime. Clothes which have 
been gassed can be disinfected by washing in running 
water for several days, by washing in nearly boiling water 
for I to 2 hours, by steaming for an hour, or by hanging 
them out in the rain. The extent of cleaning necessary 
and method employed will depend on the amount of con- 
tamination and the conditions in the field. See Chapter 
IX. 
APPENDIX 7 
GAS ATTACKS 
The enemy employs gas for two purposes-to inflict cas- 
ualties and to reduce the fighting efficiency of his oppo- 
nent. For the purpose of inflicting casualties he relies 
upon surprise, and upon taking advantage of ignorance, 
bad discipline, faulty training and defective respirators. 
To reduce fighting efficiency of our forces he seeks to 
compel the wearing of masks or to employ other protec- 
tive appliances. 
In making a gas attack the enemy seeks to generate a 
cloud of gas either directly within our own lines or in 
such a position that it will be carried by the wind into our 
lines. To accomplish this end he employs three distinct 
methods: 
Cylinder Cloud Attacks. Such attacks are employed 
more frequently in trench warfare than in open warfare, 
as there is more time to place the cylinders in the trenches 
and the stability of movement allows the cloud to drift 
over the opponent's trenches. 
Projector Attacks. Such attacks are limited to a sta- 
bilized front in which time and other circumstances per- 
mit the projectors to be brought up and placed in posi- 
tion for firing. Improvements to avoid digging trenches 
to emplace the projectors and more rapid means of trans- 
portation will broaden the use of this form of attack. 228 
APPENDICES 
Borbardments with Artillery or Trench Mortar Gas 
Shell. Such attacks are applicable in all modes of war- 
fare. 
In the case of cylinder attacks, a highly poisonous 
liquefied gas of low boiling point is liberated from cylin- 
ders placed in or near the front line. In case of projector 
or trench mortar attacks, and of attacks by artillery shell, 
the gas is inclosed in a suitable projectile and is thrown 
into the adversary's territory. There, by means of a per- 
cussion or a time fuse and a bursting charge, the shell is 
broken open and the poisonous material is liberated. The 
bursting charge is varied, depending upon whether the 
"ga,s" is a liquid, or a solid. The bursting charge is 
usually very small in the case of a liquefied gas, but often 
sufficient to give practically a high explosive effect, in the 
case of solids. A liquefied gas vaporizes when the pres- 
sure is released by the breaking of the shell, while solids 
are either atomized or vaporized by the explosion of the 
bursting charge. 
Cylinder Cloud Attacks. Gas clouds are produced by 
the sudden liberation of a liquefied gas from cylinders in 
which it is stored under pressure. The gas used is gen- 
erally chlorine, phosgene, or mixtures of chlorine with 
phosgene or chlorpicrin. Formerly cylinders were as a 
rule dug in at the bottom of the trench and connected with 
outlet pipes that led from the bottom of the cylinder out 
over the trench parapet. Now they are often piled on 
trucks or flat cars and fired simultaneously by electricity. 
When the outlet valves are fully opened, whether by hand 
or electrically, the liquid is driven out as a gas in two or 
three minutes, which, mixing with the air forms a cloud. 
This cloud may vary in appearance, due to weather con- 
ditions or to smoke mixed with it. It may be almost 
transparent and slightly green in color, or it may look like 
a thick mist. 
The cloud is carried by the wind over the opposing 
line and at times the gas has been noticeable in the rear 
areas as much as io miles from the front line. Gas 
clouds are usually slightly denser than the surrounding 
air and therefore tend to fill up trenches and hollows and 
penetrate unprotected dugouts where the gas remains 
long after the main cloud has passed. Such clouds tend APPENDICES 
229 
to follow the course of valleys. Lakes or streams do not 
affect the gas. The chief dangers from such an attack 
are due to the high concentration of gas at the moment 
of its release and to the extent of the area which may be 
covered by the gas under favorable conditions. How- 
ever, cloud gas attacks are very dependent on wind con- 
ditions and should not be made in heavy rains. They 
are best made only when upward-moving currents of air 
are not present, that is, when the sun is not shining. They 
offer a little less chance for surprise than other forms of 
attack. 
During the discharge the warning is often given by the 
hissing sound of the escaping gas, the appearance of the 
cloud, and the .odor of the gas before the main cloud 
reaches the trenches. Gas cloud attacks are feared as a 
dangerous form of attack and when they are made, every 
form of gas defense equipment is given a most severe 
test. A later development is the use of portable gas cyl- 
inders fired by electricity while lying on the ground. 
Projector Attacks. The enemy makes use of "gas 
projectors" having a range of about 1,500 meters and in 
the case of the new rifled projectors of about 3,000 me- 
ters. By this method a large number of projectiles, each 
containing about 16.5 pounds of liquefied gas are simulta- 
neously shot from smooth-bore or rifled iron tubes dug 
into the ground or set in wooden racks. The propelling 
charges are varied according to the range desired. The 
electric current for firing the charges is generated by 
hand-driven magnetos called "exploders," each of which 
fires about twenty-five projectors. On impact, or by 
means of a time fuse, the projectiles are exploded and the 
gas volatilized. By this method, the enemy is able to gen- 
erate a cloud of gas within our lines. His tactics are 
not so dependent upon weather conditions as when cloud 
attacks are made. Projector attacks call for the highest 
degree of gas discipline among the troops affected be- 
cause of the surprise which is often secured and the in- 
stantaneous formation of an extremely concentrated and 
deadly cloud of gas. Warning of an impending projec- 
tor attack may be given by: (a) Noise of installation of 
the apparatus and material, (b) Active wind observa- APPENDICES 
230 
tions on the part of the enemy, (c) Airplane photographs 
of projector emplacements, new dumps and tracks. 
When the shoot occurs a large flash or series of flashes 
may be seen in the enemy's lines, followed by a loud 
explosion, like that of an ammunition dump blowing up. 
The enemy often tries to conceal this sheet of flame by 
installing projectors behind hills so that the only warning 
given is the crash. Sentries should be warned to give 
the alarm when any sound is heard which might be inter- 
preted as being caused by projectors. The course of the 
projectiles through the air is often seen by the trail of 
sparks emitted from the time fuses, and the bombs make 
a loud whirring noise described as being similar to the 
noise of partridge in flight. In the case of the rifled pro- 
jector shell the noise is less distinctive and similar to that 
caused by ordinary artillery shell. Twelve to twenty-two 
seconds warning is usually given by the flash and explo- 
sion. 
Gas Bombardment with Trench Mortars or Artillery. 
The enemy also employs toxic substances in the projec- 
tiles shot from trench mortars or minenwerfers. With 
sufficient rapidity and accuracy of fire, it is possible for 
him to generate a heavy cloud of gas within our lines. A 
higher degree of accuracy is attained than with projec- 
tors and the bombardments can be continued indefinitely, 
whereas a projector can be fired only once during a con- 
siderable period of time. However, it is not possible by 
the use of minenwerfer to develop as high a concentration 
in as short a time and the likelihood of surprise is not so 
great. 
The use of toxic substances in artillery shell is the most 
important method of gas warfare. Batteries firing rap- 
idly and accurately against some objective, such as an- 
other battery, can develop a moderately high concentra- 
tion at a long range. Owing to the greater range and 
accuracy of artillery fire, weather conditions affect this 
use of gas less than others, although a wind of high ve- 
locity or upward currents will disperse a cloud of non- 
persistent gas so rapidly that very little damage will be 
done. Gas shells are used in various ways, according to 
tactical result desired. To produce casualties, sudden APPENDICES 
231 
bursts of lethal shell are concentrated on small targets, 
and in preparation for an infantry advance enormous 
numbers of shell containing penetrating and surprise 
gases are often employed. Harassing fire with persistent 
gases like mustard, a few shells at a time, may be con- 
tinued indefinitely against permanent positions. 
Toxic substances find a use of minor importance in 
hand grenades. In this form, the enemy employs poison- 
ous chemicals for the purpose of "mopping up" recently 
captured trenches and dugouts. 
The following is a convenient form to be used for mak- 
ing reports on gas attacks: 
AMERICAN EXPEDITIONARY FORCES 
Defense Division, Chemical Warfare Service 
REPORT ON GAS ATTACK 
Serial No 
(Date of Report) 
Corps 
Division 
Unit Location 
From M , 19..., to M , 19.... 
Method of attack (shells, cylinders, projectors) 
No. of projectiles Caliber Gas used 
Wind direction Velocity ....M.P.S Tempera- 
ture Humidity 
Character of terrain (woods, sloping ground ravine, 
swamp, etc.) 
Area of terrain and length of front affected 
No. of troops exposed 
Duds found at (Coordinates) ... .No Caliber 
Markings 
Total casualties including deaths Total deaths 
Lung cases Eye cases or burns 
Causes of casualties (approx. No. from each cause; fail- 
ure to put on mask, premature removal, etc.) 
Length of time respirators were worn 
Was any part of gassed area evacuated? 232 
APPENDICES 
At what time? 
Was attempt made to relieve units required to remain in 
sector ? 
At what time (in the case of mustard gas) was disinfec- 
tion of ground begun? 
Completed 
Remarks: (should include any new tactical use of gas, any 
suggestions, etc.) 
Signed 
APPENDIX 8 
DEFENSE AGAINST GAS 
A system of defense against gas must necessarily be 
wide in its scope and continuous in its action, and on the 
other hand there is no type of enemy warfare which can 
be as successfully resisted as gas. Against well-disci- 
plined troops, some of the most violent gas bombardments 
have failed to secure a single casualty, though any laxity 
is sure to result in more or less serious losses. 
It is the duty of commanding officers to familiarize 
themselves with the nature of gas, and the means of de- 
fense against it. The protective appliances are con- 
stantly being improved as gas warfare develops, and when 
rightly used, they give very complete protection against 
all forms of gas. In warfare, any substance which is 
used for its poisonous or irritating effect may be called a 
gas, regardless of whether it is a "true gas," a mist of 
fine drops, a cloud of poisonous dust, an ordinary liquid, 
or a solid. 
There are two groups of warfare gases. The first 
group, of which chlorine is an example, consists of sub- 
stances that are true gases under ordinary conditions and 
form gas clouds immediately upon opening the container 
in which they are stored. Those of the second group, 
typified by mustard gas, form vapors only very slowly APPENDICES 
233 
unless scattered by shell explosion or warmed by the heat 
of the sun. Even an extremely small amount of certain 
gases if breathed sufficiently long, will cause a casualty. 
A man some distance from a shell hole containing poi- 
sonous liquid may become a casualty through inhaling the 
vapor or by its condensation on his body, even if no shell 
have fallen for several hours. It is important that this 
be explained so that the men may appreciate the danger 
of gas, and at the same time realize that there is nothing 
mysterious or supernatural about it. 
In order to cut down gas casualties to the absolute 
minimum, the following measures must be taken: (a) 
Thorough training and drill of troops in the use of pro- 
tective appliances so that they can adjust them accurately 
under all conditions and perform all duties while wear- 
ing them, (b) Frequent and rigid inspection of all pro- 
tective equipment, (c) Absolute obedience to regulations 
in regard to carrying the respirator in danger and alert 
zones. (d) Training all troops to recognize gas at- 
tacks. (e) Installation of adequate gas alarms and in- 
struction of sentries in their use. (f) Teaching all offi- 
cers and gas non-commissioned officers the properties of 
enemy gases, proper methods of defense against them, 
and action to be taken in situations likely to arise, (g) 
Practice in wearing respirators for long periods, (h) 
Wearing respirators as long as gas is present. 
Experience has shown that numerous casualties occur 
through failure to warn men promptly when the enemy 
makes a gas attack. Officers are responsible that arrange- 
ments are made for the communication of the gas alarm 
to all ranks under their command in the shortest possible 
time. The need for quickness in giving the gas alarm is 
imperative; a few seconds delay, particularly in the case 
of projector attacks, makes a great difference in the num- 
ber of casualties. Sentries must be posted over all men 
sleeping in dugouts. Whenever there is danger of pro- 
jector attacks, men should be prevented from sleeping 
within 1,500 yards of the enemy front line, if tactical re- 
quirements permit. On detecting the presence of gas, 
sentries shout "gas," put on their respirators and imme- 
diately spread the alarm in every possible way. 
The method of giving the alarm varies with the nature APPENDICES 
234 
of the attack. In cylinder and projector attacks it is nec- 
essary to warn troops over extensive areas, which may 
be traversed by a dangerous concentration of gas, while 
the effect of gas shell bombardment is much more local, 
and it is necessary to alarm only troops in the immedi- 
ate neighborhood of the bombarded area. Any device 
may be used as an alarm for gas attacks which gives a 
loud and distinctive noise, and does not require the use of 
lungs. Improvised alarms, such as church bells and empty 
shell cases are in use, as well as Klaxon horns, wooden 
rattles and steel triangles. Such light signals as may be 
approved by Division Commander on recommendation of 
the Division Signal Officer and which do not conflict 
with those already in use, may be employed for gas alarms. 
Commanders of companies on the move should make sure 
that a sufficient stock of portable alarm devices is always 
on hand. 
The protection of dugouts against gas has proven of 
great value especially in the case of gas of high persist- 
ency, which may necessitate the wearing of the respirator 
in an area for long periods. The entrance to all dugouts 
and shelters of sufficiently good construction within the 
"Alert" zone should be provided with two gas tight doors, 
or with two curtains of gas proof material with a space 
of several feet between them, thus forming a gas lock. 
Each curtain should be fitted so as to give a tight joint, 
over the whole frame of door, stopping all draughts. Not 
only should dugouts and cellars be provided with frames 
and blankets, but care must be taken that the cracks be- 
tween the frames and the earth or rock walls are made 
gas tight. Curtains should always be kept moistened or 
oiled and rolled up when not in use. Unless this is done, 
the curtains are useless. All dugouts which have been 
made really gas proof, are posted with a sign "Gas Proof." 
In medical and signal dugouts particular care should be 
taken to provide this protection so that officers and men 
can work during gas attacks without wearing respirators. 
Precautions to be observed in dugouts in case of gas 
attacks are as follows: (a) Lower curtains immediately, 
(b) Wake all sleeping men. (c) Put out all fires, (d) 
Stop up any holes or flues, (e) Prevent passing in and 
out as much as possible, (f) In case of passage in or out, APPENDICES 
235 
only one man must pass through at a time. Only one cur- 
tain must be raised at a time, and curtains must be low- 
ered as quickly as possible, (g) Men entering from 
gassed areas must remove outer clothing and leave it in 
the gas lock. 
After a cloud attack some of the gas will remain in un- 
protected dugouts, trenches and hollows in the ground. 
A certain amount will also be absorbed in blankets and 
clothing. Any gas present in the air may be removed 
rapidly by ventilation. In shallow dugouts and trenches, 
fanning with coats or empty sand bags will produce a 
sufficient draught for this purpose, but all dugouts are 
cleared most rapidly and effectively by means of a fire. 
In dugouts provided with a single exit, the best results 
are obtained if the fire is placed in the center of the floor 
of the dugout. In those provided with two or more exits, 
the fire should be placed at the inner end of the exit pas- 
sage farthest from the wind. 
After a bombardment with mustard gas, in addition to 
gas remaining as described above, some of the liquid will 
remain on the ground near the shell craters, on the floor 
and walls of dugouts and emplacements that have re- 
ceived direct hits, in piles of straw and rubbish, in straw 
mattresses, clothing and equipment. This liquid may 
continue to give off gas for long periods and every possi- 
ble means must be taken to destroy it immediately. Pum- 
ice soaked in phosgene should be covered deeply with 
earth (not chloride of lime), or the position evacuated 
until it ceases to give off gas. 
There have been cases reported of food which has been 
exposed to gas causing ill effects. All food and water 
should be kept covered. No food that has an unusual 
taste or odor after a gas attack or bombardment should be 
eaten. Casualties have more frequently been produced 
by the use of contaminated water from shell craters. All 
water from shell craters should be regarded as dangerous 
until proved to the contrary, and every effort should be 
made to use water from other sources. Blue Cross, con- 
taining arsenic, dissolves in water, making it highly poi- 
sonous, and this is not remedied by boiling. 
Many gases, particularly phosgene and chlorine, have 
a corrosive action on metals. This action is greatly as- 236 
APPENDICES 
sisted by moisture which dissolves and retains the gas so 
that corrosion continues until the surface is cleaned. Mus- 
tard gas liquid will also corrode brass. Metal surfaces 
which are covered with mineral oil are not affected, pro- 
vided they are cleaned and re-oiled after exposure. 
The Division Commander is responsible for the proper 
training and instruction of his command in gas defensive 
measures. The presence or absence of gas casualties 
under a gas attack forms a basis for estimating the effi- 
ciency of his command. The Chemical Warfare Service 
provides the division and corps gas officers with suitable 
samples of the various kinds of gases, especially those of 
most frequent use, for instructing the personnel in the 
identification of the presence of gases. These samples 
are prepared in such form that they may be easily trans- 
ported without the necessity of increasing the allowance 
of transportation authorized for moving gas supplies. 
When in training areas, quantities of various gases are 
supplied for the purpose of infecting areas and shell holes 
as they occur under actual conditions of warfare. 
Organization. Commanding officers of all units are 
held responsible that all the anti-gas appliances for pro- 
tecting their men are maintained in perfect condition, and 
that all ranks under their command are thoroughly trained 
in the use of these appliances, and in all measures which 
may affect their safety against gas, including identifica- 
tion of the presence of gases and the identification of 
gas attacks. 
Battalion, regimental, division gas officers and assist- 
ants are appointed to aid in seeing that all anti-gas meas- 
ures are efficiently carried out. It is their duty to bring 
any efficiency in gas discipline or protection to the notice 
of the proper commanding officer when necessary. 
A gas officer is appointed by the unit commander for 
every regiment, for every battalion and for separate 
units; a gas non-commissioned officer is assigned as assist- 
ant to each of these gas officers, and two gas non-commis- 
sioned officers are appointed for each company. All gas 
officers and gas non-commissioned officers are relieved 
from all duties which might interfere with their duties as 
gas officers. These gas officers and gas non-commissioned 
officers, as well as other officers and non-commissioned APPENDICES 
237 
officers chosen for their replacement, are selected on ac- 
count of their special qualifications. They are required 
to take a course of training to fit them for their duties. 
Regimental and other commanding officers consult their 
gas officers before relieving the gas non-commissioned 
officers serving them in order that other non-commis- 
sioned officers, properly instructed, may be selected as re- 
placement. 
The commanding officers of units are responsible, not 
only for the gas discipline of attached troops, such as 
machine gun companies, detachments of engineers and 
field signal men operating within their areas, but are also 
responsible for the gas training of these troops, and see 
that they receive training in gas defense equivalent to 
the training given their own units. 
Gas non-commissioned officers in such attached troops 
are reported to the gas officer of the unit to which they 
are attached (battalion or regimental). In case of de- 
tachments which are smaller than a platoon, and which 
have no gas non-commissioned officer of their own, one 
of the gas non-commissioned officers of the unit with 
which they are being rationed, is assigned to them to act 
as gas non-commissioned officer, in addition to his duty 
with his own company. 
Training and Inspection. In addition to training at the 
schools and in the training areas, all ranks whose duties 
require them to enter the "Danger" zone should continue 
respirator drill as may be directed by the Division Com- 
mander. Respirators must be worn at least four hours 
each week, but during this time usual drills and other 
duties should be performed. Once each month all com- 
batant troops should wear the respirator for four consecu- 
tive hours. Respirator drill should include the adjust- 
ment of the respirator while the helmet is worn and also 
the adjustment and wearing of the respirator in the dark. 
Respirators, alarm systems, protected dugouts, and such 
other gas defense measures as may exist under varying 
conditions within a divisional area, should be inspected 
twice each week by the proper gas officers. In the "Alert" 
zone company commanders will provide for similar daily 
inspection by the gas non-commissioned officers. Any de- 
ficiencies should be called to the attention of the company 238 
APPENDICES 
commander concerned, and of the battalion commander. 
As many dugouts as possible should be made adequately 
gas proof. No dugout curtains or other devices appar- 
ently protecting against gas should be maintained in dug- 
outs which are reported not to be adequately gas-proof. 
APPENDIX 9 
FUNCTIONS OF GAS OFFICERS 
The essential qualities of a gas officer are technical 
knowledge, tact, courtesy, initiative, ingenuity, and ener- 
getic perseverance. He must bear in mind that his sup- 
ply and administrative duties are not the most important, 
and that one of his most important duties is to advise with 
respect to gas offense operations. These duties cannot 
be properly performed from an office in the rear. 
The following enumeration of functions of corps and 
division gas officers is suggestive and not all inclusive: 
Administration, (a) Secure and employ as near full 
allowance of officers and enlisted men as practicable in 
corps (or division) office, (b) Keep lists up to date of 
regimental and battalion gas officers and non-commis- 
sioned officers, (c) Study the personality of subordinate 
gas officers. Attempt to make the best use of them by 
suitable assignments, and to correct faults and weaknesses 
when possible, (d) Departmentalize, as far as practicable, 
the work of the corps (or division) gas personnel, (e) 
Place all enlisted personnel immediately under a respon- 
sible non-commissioned officer in charge of office, (f) 
Secure, if practicable, separate quarters for enlisted per- 
sonnel. (g) Know by name and rank each officer on 
the staff and the nature of his duties, (h) Insure that' 
the required number of regimental and battalion gas 
officers and non-commissioned officers are trained at prop- 
er schools. Maintain a written record of training of gas 
personnel, commissioned and non-commissioned, and their 
ability, recommending advance of those who discharge APPENDICES 
239 
their duties satisfactorily whenever a vacancy exists, (i) 
Secure as near full allowances of transportation as prac- 
ticable. (j) Maintain a filing system, emphasize care of 
and making of maps, form and substance of reports and 
correspondence, appearance of office, (k) Keep a war 
diary. 
Relations within corps (or division'), (a) Maintain 
an intimate liaison with all staff departments, (b) Cul- 
tivate interest in gas among all officers by congenial, un- 
obtrusive methods, (c) Request action of G-3 on reports 
and recommendations relating to gas discipline, training 
and supplies, (d) Secure official publications of neces- 
sary orders, such as zone regulations, (e) Secure coop- 
eration of Military Police in enforcement of orders relat- 
ing to gas defense, (f) Secure all necessary information, 
such as maps, reports and circulars concerning enemy op- 
erations from G-2 (intelligence), concerning our own 
movements from G-3 (Operations), concerning casual- 
ties from the Corps (or Division) Surgeon's office, con- 
cerning casualties and our own posts of command from 
the Statistical Office, (g) Cooperate with representative 
of Inspector General and Medical Gas Officer. 
Operations, (a) Furnish counsel in gas matters as re- 
quested by the Commanding General, Chief of Staff, G-3, 
or (Corps) Artillery Officer, (b) Act as liaison between 
gas troops operating in corps (or division) area and 
corps and division staffs, establishing understanding on 
the part of the staff and an appreciation of their potential 
value. The Division Gas Officer will aid in establishing 
similar relations between gas troops and units with which 
they are to act in the line, (c) Furnish gas troops with 
all available information concerning suitable targets and 
movements involving the possibility of activity on their 
part, (d) Devise plans for use of gas, submitting them 
to G-3 or to Commanding Officer of Gas Troops con- 
cerned where his organization is affected, (e) Establish 
relations with artillery brigades (or brigade) cultivating 
interest in gas. (f) Maintain liaison with Munitions Offi- 
cer and Artillery Operations Officer, also Salvage Officer, 
and be cautious in recommendations of artillery gas pro- 
gramme, leaving all matters of recommendation which are 
exclusively in the field of artillerists, (g) Report without 240 
APPENDICES 
delay direct to the Army Chief of Chemical Warfare 
Service all gas offensive operations executed by troops 
of the division (or corps), submitting a copy of such re- 
port to G-3. 
Supplies, (a) Study carefully the means of supply and 
probable future needs of the division (or corps), (b) In- 
jure an adequate supply of timely requisition on the near- 
est advance army depot, but keep the stock in corps park 
or division dump as small as compatible with local needs, 
(c) If not near an advance depot see that requisitions on 
the base or intermediate depots are placed with G-4 of the 
army in ample time to secure supplies. 
Subordinate Units, (a) Under such instructions as 
may be issued from headquarters, make periodic inspec- 
tions with a view toward determining the state of gas 
discipline, training and supplies, reporting defects to the 
Division (Regimental) Gas Officer and Commanding Of- 
ficer of unit concerned. When corrective measures are 
not applied, submit a special report to G-3 for information 
of the Commanding General, (b) Keep the Commanding 
General advised of the state of gas training, discipline and 
supplies in divisions assigned to corps (or units within 
the division, (c) Advise next senior Gas Officer on same 
subject, sending copy of such report to the Chief of 
Chemical Warfare Service. (d) Assist the Division 
(Regimental and Battalion) Gas Officers by counsel and 
suggestion. (e) Study the conditions within divisions 
(regiments, etc.) through routine report and personal in- 
terview. (f) Encourage criticism and suggestion from 
Division (Regimental and Battalion) Gas Officers, (g) 
Be watchful at all times of gas personnel who, through 
temperamental or other unfitness, tend to bring the Chem- 
ical Warfare Service into discredit and recommend to the 
Chief the transfer of such officers and men to other work, 
(h) Insist upon the use of proper channels of communi- 
cation. (i) Accustom troops to the use of smoke, high 
explosives, and thermit by gas troops through demonstra- 
tion and brief lectures. 
Corps Troops, (a) Maintain gas discipline, training 
and supplies, (b) Undertake training of gas non-com- 
missioned officers in the units not as a whole identified 
with front line activity (such as remount squadron, etc.). APPENDICES 
241 
(c) Check closely situation concerning replacement bat- 
talion and the sending of replacements to the line without 
proper anti-gas equipment, (d) Interview gas officers 
and non-commissioned officers of corps troops frequently 
for purpose of securing from them helpful suggestions 
and criticism. 
Casualties, (a) Keep an accurate account of casual- 
ties noting particularly causes, avoidability, fatigue and 
malingering cases, the nature of gas responsible for cas- 
ualty, tactical use of that gas, ratio of shell to casualties, 
(b) Analyze periodically the proportion of casualties at- 
tributable to the several gases as indicated by symptoms 
and recollection of patients respecting smell and appear- 
ance of gas. (c) Submit report to Commanding General 
through G-3 when facts and findings justify, (d) Coop- 
erate with Medical Gas Officer in securing data concern- 
ing methods of relief of gas affections and in giving them 
publicity within the corps (or division). Notify the Chief 
of Chemical Warfare Service of all such methods in use 
in the unit, (e) Take steps to prevent the needless salv- 
age by hospitals of gas equipment of patients. 
Enemy Material and Intelligence, (a) Secure all ma- 
terial, documentary and otherwise, of any gas interest 
through divisional (regimental) gas personnel, the salvage 
officers, G-2, and miscellaneous sources, and, if practicable, 
by examination of enemy dugouts, dumps and positions in 
immediate wake of infantry advance, (b) Utilize all 
available means of transportation for removal of non-mail- 
able material to nearest Advance Army Gas Depot, noti- 
fying the next senior Gas Officer or find out where it is 
deposited, sending copy of report to Chief of Chemical 
Warfare Service, (c) Deliver all non-gas intelligence 
thus secured to G-2. (d) Secure, if practicable, transla- 
tion of gas documents before forwarding them when data 
is likely to be of immediate importance to Corps (divi- 
sions). (e) A set of enemy fuses and typical gas shell, 
sectioned, should be kept at the gas office for information 
of all concerned. 
Training of Divisions, (a) When Division is in train- 
ing recommend to G-3 to establish conferences of regi- 
mental and battalion gas officers and schools for gas non- 
commissioned officers, (b) Recommend to G-3 to 242 
APPENDICES 
establish a series of lectures, demonstrations, inspections 
and drills for the enlisted personnel of the division. 
The following is a suggestive digest of the functions of 
a Regimental and Battalion Gas Officer. It should be 
noted that responsibility for all measures taken in chem- 
ical warfare, whether in offense or defense, rests ulti- 
mately upon the commanding officer concerned, and the 
gas officers concerned are under their command. Usually, 
either the commanding officer of the regiment will order 
his gas officer to follow the technical advice of the Divi- 
sion Gas Officer, or this may be ordered by higher author- 
ity. (a) Keep an accurate record of training and ability 
of subordinate personnel, recommending such advancement 
as may be merited and practicable, (b) Keep the gas 
personnel advised of the latest available data, holding 
frequent conferences and inviting suggestion and criti- 
cism. (c) Exact strict compliance with orders relating 
to inspection by subordinate personnel, condition of ma- 
terial, gas discipline and reserve supplies by means of 
personal supervision and frequent inspections, (d) Insure 
the immediate availability of authorized reserve anti-gas 
supplies, their suitable transportation and proper issue, 
(e) Advise commanding officers of the proper precautions 
to be taken in anticipation of gas attacks, and in the event 
of such attacks keep informed concerning all action taken, 
(f) Minimize false alarms and supervise instruction to 
sentries, insuring active liaison with gas personnel of 
subordinate and superior commands, (g) Secure suffi- 
cient first aid relief in exposed areas, (h) Furnish 
counsel to the Commanding Officer in gas matters and 
stimulate interest in and understanding of the use of gas 
on the part of all officers, (i) Furnish liaison between 
the command and gas unit operating therewith, insuring 
sufficient understanding by troops of nature of proposed 
activity of gas unit operating therewith, in order to 
enable them to take full advantage thereof, (j) Report 
accurately and promptly concerning the enemy use of gas 
and its effect. In case of artillery gas officers, report in 
addition concerning delivery of gas upon enemy objec- 
tives. (k) Secure strict compliance with zone regulations 
and punishment of offenders. (1) Minimize waste of 
anti-gas material, applying disciplinary measures to of- APPENDICES 
243 
fenders and insuring the full and proper use of all anti- 
gas supplies, (m) Advise the next senior gas officer 
of the location of finds of enemy gas material or cause 
prompt delivery thereof to his office. 
Inspections of divisions by corps gas officers and of 
regiments by division gas officers should be frequent and 
thorough thereby stimulating initiative and interest of 
subordinate gas personnel, furnishing basis for the re- 
moval of the unfit, advancement of the meritorious, and 
securing helpful suggestions for the improvement of the 
Service. 
In general, the basis of inspection should be the deter- 
mination by interview, of the activities of the Gas Officer 
of the unit inspected and the instructions issued by him, 
followed by investigation of conditions in subordinate 
units, and the manner in which existing instructions are 
complied with by the gas personnel of these subordinate 
units. 
The Gas Officer should obtain maps and information 
regarding enemy dispositions and study the character of 
the enemy terrain with the view of selecting favorable 
targets for gas. He should study friendly terrain in order 
to select favorable positions for emplacements. Informa- 
tion should be obtained from the Chief of Artillery re- 
garding the availability of guns of various types and cali- 
bers. He should also obtain from the munitions officer 
information regarding the material available for use. 
The Commanding Officer of gas troops should be con- 
sulted regarding the use of cylinders, projectors and 
trench mortars, their availability and the feasibility of 
any project which might be contemplated. 244 
APPENDICES 
APPENDIX 10 
CASUALTIES BY GAS IN THE AMERICAN EX- 
PEDITIONARY FORCES 
Admission, Enlisted Men and Officers 
Officers 
Enlisted Men 
Total 
Enlisted 
White 
Colored 
Color Not 
Stated 
Gas, asphyxiating 
Gas, poisonous (Kind not 
3 
106 
3 
15 
124 
stated) 
1,201 
26,050 
535 
8,277 
34.812 
Chlorine 
32 
1,654 
37 
199 
1,890 
Mustard Gas 
822 
23,084 
482 
3,48o 
27,046 
Phosgene 
415 
5,693 
66 
939 
6,698 
Yperite 
30 
606 
46 
249 
901 
Arsine 
30 
350 
125 
94 
569 
Total 
2,533 
57.543 
1,294 
13,203 
72,040 
Total admissions from gas, enlisted men 72,040 
Total deaths from gas, enlisted men 1,168 
Total deaths from gas, officers 26 
Total admissions, Battle injuries (including gassed) officers 8,633 
Total admissions, Battle injuries, Enlisted men (including gassed).... 231,873 
Figures include all reports rendered to the Surgeon General from the American 
Expeditionary Forces arriving in Washington before June 1, 1919- Do not 
, include any killed in action. 
Total Gas Casualties 75.767 
Total of all Casualties 273,869 
Percentage of Casualties, due to Gas 27.6% 
Total deaths due to Gas x,i94 
Percentage of Gassed Cases, resulting in death 1.5% 
Percentage of battle wounded cases resulting in death (47.715/165,933) 28,7% 
Percentage of battle deaths due to Gas (1,194/48,909) 2.4% 
Comparison Based on Official Figures APPENDICES 
245 
APPENDIX ii 
ANTI-GAS MEASURES AFFECTING SPECIAL 
ARMS 
It is unlikely that Cavalry, when mounted, will encoun- 
ter high concentrations of gas from a gas cloud, or even 
from gas shells. It will probably be found therefore that, 
when acting as mounted troops, the P. H. helmet will be 
adequate protection, besides being less cumbersome for 
troops depending on their mobility. 
On the other hand, Cavalry used to supplement Infan- 
try in the line, or employed as working parties in or near 
the trenches, must be equipped for gas defense in the 
same way as other arms. In this case, it is impossible to 
wear the bandolier over the shoulder when the box res- 
pirator is worn in the "Alert" position. During the Gas 
Alert period, mounted troops must therefore wear the 
bandolier round the waist. 
Artillery are probably more liable than any one else to 
bombardment with gas shells, both poisonous and lachry- 
matory. Owing to the suddenness of shell attacks and 
the long period that the neighborhood of a battery may 
be affected by lachrymators, it is essential that the fol- 
lowing points be noted: 
(a) Where, owing to circumstances, box respirators 
are not actually worn on the men, they must be hung 
separately and within easy reach of the owners. (They 
should not, if possible, be hung in the actual gun emplace- 
ments, owing to the concussion being liable to displace the 
chemicals in the box.) If this course has to be adopted, 
the respirators should be ready prepared with the haver- 
sack sling shortened by means of the tab and stud and the 
slack of the sling tucked under the mask as in the "Alert" 
position. The satchel flap should be unbuttoned, but kept 
in position. 
(b) Men must be well practiced in wearing their box 
respirators for long periods and in serving their guns 
while wearing respirators or anti-gas goggles. 246 
APPENDICES 
Forward observing parties must take all the precau- 
tions laid down for Infantry. 
The following precautions apply to medium and heavy 
trench mortars as well as to guns and howitzers: Bat- 
teries which are in constant danger of gas attacks, wheth- 
er from gas clouds or gas shells, should keep all bright 
parts of the gun or mortar, carriage, mounting and ac- 
cessories well coated with oil. Sights and all instruments 
should also be smeared with oil and protected with covers 
when not in actual use, care being taken that the oil does 
not come in contact with any glass or find its way into the 
interior of the instrument. Cartridge cases of the am- 
munition stored with the battery and all uncapped fuses, 
or fuses which have been removed from their cylinders, 
should be wiped over with oil as soon as possible and 
protected with a cover. 
All bright parts of guns and trench mortars, together 
with all accessories and spare parts exposed to the gas, 
must be cleaned and wiped dry as soon as possible after 
the attack, and in any case within 24 hours, after which 
they should be thoroughly coated afresh with oil. The 
same applies to the whole of the ammunition still in the 
battery position. Ammunition which, for any reason, 
had not been oiled, must be cleaned and oiled. It is de- 
sirable to expend it as soon as possible. 
Aiming points and aiming posts are liable to be ob- 
scured by the gas cloud and arrangements should, there- 
fore, be made in every battery to meet this eventuality 
by providing gun pits with means to check the line of fire 
if necessary, without depending on the use of aiming 
posts. 
Enemy gas attacks may be executed for purposes other 
than the preparation of a subsequent infantrv attack. 
During the gas discharge a heavy artillery fire on the 
actual trenches whence the gas is issuing is the best way 
of dealing with the situation. Also it is essential that the 
gas discharge should be interfered with as early as possi- 
ble, as the opening periods of the discharge are the most 
effective. 
To insure an effective and immediate artillery fire the 
following points require attention: (a) Certain how- 
itzer batteries should be detailed to open a rapid fire APPENDICES 
247 
for a short time as an anti-gas measure, (b) Only cer- 
tain portions of the enemy's front trenches can be used 
for gas discharge in any given wind and these can easily 
be indicated on any accurate trench map. Each battery- 
charged with the task of hampering an enemy gas attack 
should be provided with a map and a table, showing from 
what portions of the enemy's lines (within the battery's 
zone of action) gas can be discharged in any given wind. 
Nothing in the foregoing in any way affects the respon- 
sibility of artillery for dealing with any infantry attack, 
or for the execution of counter-battery work. 
Tunneling companies are again reminded that neither 
the box respirator nor the P. H. helmet affords protec- 
tion against mine or explosion gases. Owing to the diffi- 
culty in clearing gas, especially lachrymatory gas, from 
mine-shafts and galleries, the entrances to mine-shafts 
should be protected from gas by blanket curtains in the 
manner described for dug-outs. The enemy has occa- 
sionally attempted to render the galleries untenable by 
the use of lachrymatory bombs in conjunction with the 
explosion of a charge. If this is done, goggles will gen- 
erally be found sufficient protection; but if the concentra- 
tion is so high as to affect the nose or lungs, the box res- 
pirator must be worn if work has to be continued. 
It is essential that telephone operators should be able to 
work as much as possible during a gas attack without 
wearing respirators or helmets. Signal dug-outs must, 
therefore, be particularly carefully protected against gas, 
so as to allow this to be done. Telephone operators must 
be specially practiced in using their instruments when 
wearing box respirators or helmets. The head-piece of 
the receiver will be worn over the helmet. The buzzer 
should be used when the respirator or helmet is worn. 
Linesmen must receive plenty of practice in carrying on 
their work, both at night and in the daytime, while wear- 
ing box respirators and also goggles. 
The only effective method of preventing corrosion of 
electrical apparatus during a gas attack is to prevent the 
gas reaching it, and the best way of doing this is to have 
the signal shelters and offices thoroughly protected against 
gas. As the corrosive effect on damp instruments is 
very much greater than on dry instruments, the shelters 248 
APPENDICES 
should be kept as dry as possible. During a gas attack 
telephones must be kept in their leather cases and unless 
the buzzer key is being used the leather flap must be kept 
down, leaving only the cords with receiver and hand-set 
out of the case. The backs of switchboards and buzzer 
exchanges must be kept closed. All apparatus, such as 
magneto telephones, test boards, spare instruments, etc., 
which it is not essential to have uncovered, should be 
well covered up with cloths, blankets or coats, etc. 
After a gas attack, telephone apparatus that has been ex- 
posed to gas should be treated as follows: The ends of 
the wires should be removed from terminals and cleaned 
by being scraped with a knife, wiped with a damp cloth 
and dried. Terminals, exchange plugs and all exposed 
metal work should be cleaned first with a damp and then 
with a dry cloth. This process should be repeated after 
12 hours have elapsed. The metal work of the leather 
case of the telephone and of other instrument cases should 
be cleaned with oil in the same way as rifles, etc. The 
internal portions of the instruments should not be inter- 
fered with. If an instrument has been kept closed or 
covered up, it is very unlikely that internal portions will 
have suffered; but if these portions show signs of corro- 
sion, the instruments should be sent back to Division or 
Corps Headquarters to be dealt with by an instrument 
repairer. 
When the gas alarm is sounded, all baskets containing 
pigeons should be placed in the special anti-gas bags 
provided for this purpose, or placed in gas-proof shelters. 
If for any reason the birds cannot be protected from the 
gas, they should be liberated at once. Anti-gas bags 
should always be kept near baskets containing birds, and 
should be regularly inspected. Pigeons can be utilized 
during a gas attack. Experience has proved that they 
fly through any gas cloud, but it is imperative that the 
bird should be exposed to the gas for as short a time as 
possible. The message and carrier should, therefore, be 
prepared and if possible, fastened to the pigeon's leg, be- 
fore the bird is exposed to the gas. Twenty seconds 
should suffice to fix a carrier and liberate a bird. INDEX 
A 
Absorbent substances. 3 
Adjutant and personnel of- 
ficer, 127 
Airplane flares, 167 
Akron-Tissot mask, 37 
Alert position, 63, 174, 175, 
186, 188, 189, 190, 194, 195 
Alert zone, 174, 234 
Altitude flying, 166 
American gas shell, 68, 78 
American projector, 143 
American Stokes bomb, 139 
American Tissot respirator, 
184, 185 
American trench mortar 
fuses, 142 
Anilite, 7 
Anti-dimming outfit, 184 
Anti-dimming tubes, 39 
Anti-gas measures, 245, 246, 
247, 248 
Army message center, 151 
Artillery chemical shell, 53 
B 
Back barrages, 60 
Barrages, 59, 60 
Battalion gas officers, 174 
Battalion supply officer, 135 
Benzyl chloride, 23 
Bertholite, 45 
Blanketing fire, 58 
Bleaching powder, 39 
Bombardment of area, 58 
Bombs, 100, 125, 138, 139, 166, 
169, 170, 171 
Boosters, to, 24 
Box respirator, 27, 28, 65 
British Allways fuse, 41 
British ballistite charges, 141 
British cordite charges, 140 
British E. C. 3 powder, 140 
British Mills pistol head. 141 
British "S" mixture, 93, 94 
British Sutton fuse, 142 
Bromacetone, 199 
Brombenzyl cyanide, 23. 45, 
46. 114, 117, 120, 124, 199 
Bromine, 22, 23 
Brom-ketones, 10, 203 
Bureau of Mines, I, 3 
Bursts, 49, 57 
C 
Calcium picrate, 19 
Camouflage, 150, 163 
Canister ingredients, 27, 32 
Canisters, 31, 32, 33, 36, 39, 
184, 187 
Carbon, 9, 27, 33, 34, 35 
Carbon monoxide, 20, 204, 
205, 206, 207, 208 
Carbonylchloride, 200 
Caustic soda, 18 
Chanard incendiary bombs, 
166, 169, 170, 171 
Charcoal, 9, 27, 33, 36, 37 
Chemical adviser and intelli- 
gence officer, 127 
Chemical artillery ammuni- 
tion, 68, 74 
Chemical assistant, 130 
Chemical hand grenade, 103 
249 250 
INDEX 
Chemical shell fillings, 75, 76. 
85, 86, 89, 90 
Chemical shell fuses, 81, 82, 
83, 84, 85 
Chemical warfare service, I, 
5, 8, 11, 15, 25 
Chemical weapons, 100 
Chlorine, 15, 17, 23, 44. 45, 
199, 208, 209, 210, 211, 212 
Chlorine plants, 12, 18, 20 
Chlor-ketones, 10 
Chlorpicrin, 18, 19, 23, 25, 26, 
41, 42, 44, 45, 46, 114, 117, 
120, 121, 199, 201, 203, 212 
Chlorpicrin plants, 12, 15, 19 
Cloud gas, 48, 49, 50, 115, 120, 
125 
Collognite, 46 
Company commander, 133 
Company supply officer, 134, 
135 
Construction assistant, 131 
Containers, 26 
Cordite charges, 140 
Corps messenger center, 151 
Corps troops, 240 
Counter-battery fire, 57 
Cyanogen chloride, 199 
Cylinder cloud attacks, 227, 
228 
D 
Danger zone, 174 
Defense against gas, 232, 233, 
234, 235, 236 
Destruction fire, 56 
Diazomethane, 10 
Dichlorethylarsine, 46 
Dichlorethyl sulphide, 21, 46, 
199, 222 
Diphenylchlorarsine, 10, 41, 
42, 44, 46, 117, 199, 203 
Diphenylcyanarsine, 44, 46 
Diphosgene, 44, 46, 199, 201, 
212 
Disinfecting service, 174 
Dispersoid division, 9 
Division gas officer, 175, 177, 
179 
Division message center, 151 
Dreyer oxygen apparatus, 
168 
Dud gas shell, 66, 181 
Dugout blankets, 39 
Dummy bombs, 166 
E 
Edgewood arsenal, 2, 5, 12, 
14, 15, 16, 21, 23, 25 
Effectiveness of gas, 50 
Ethyldichlorarsine, 44, 203 
Ethylidioacetate, 45, 199 
F 
Fake gas attacks, 61 
Filling plants, 12, 14, 24, 25 
Flame throwers, 2 
Flaming liquid section, 8 
Fluorine, 9 
F. M. Shell, 60, 77 
Four-inch Stokes mortar, 11 
Fragmentation, 7 
French training smoke bombs, 
172 
Fuses, 79, 91, 92, 125, 141, 142, 
146 
G 
Gas, 22, 30, 40, 41, 48, 49, 73, 
119, 125, 152, 166, 176, 235 
Gas alarms, 174, 176, 177 
Gas attacks, 227, 231 
Gas bombardment, 52, 53, 54, 
56, 57, 59, 228, 230, 235 
Gas bombs, 21, 139 
Gas casualties, 233, 241, 244 
Gas clouds, 50, 51, 52 
Gas defense division, 38 
Gas defense equipment, 27 
Gas grenade, 100, 105 
Gas hand grenade, Mark II, 
104 INDEX 
251 
Gas mask day, 35 
Gas masks, 1, 4 
Gas officer, 55, 148, 174, 236, 
238, 239, 240, 241, 242, 243 
Gas operations, 125 
Gas regiment, II, 125, 126 
Gas safety zone, 55 
Gas sentries, 174, 176 
Gas shell dumps, 53 
Gas shells, 2, 50, 53, 62, 63, 
64, 65, 66, 68, 71, 73 
Gas troops, 125, 126, 127, 149, 
152, 156, 157, 158 
Gas zones, 174 
Gas zones of dispersion, 40, 
5° 
Grenade incendiaire a main, 
100 
Grenades, 100, 115 
H 
Halogen ethers, 10 
Hand grenades, 7, 100, 101, 
102. 103, 104, 105, 107, 108, 
109, no 
Hand grenade section, 7 
Hand or rifle grenade, Mark 
I, 106 
Harassing fire, 57, 59, 122, 
123 
Heavy fire, 57 
Horse masks, 27, 39 
Horse respirators, 184, 193 
Hydrocyanic acid, 46 
Hydrogen selenide, 10 
I 
Incendiaire et fumigene 
hand grenade, 105. 
Incendiary bombs, 139, 166, 
171 
Incendiary grenades, 100 
Incendiary section, 8 
Incendiary shell, 68 
Infantry training, 159, 160 
Interdiction fire, 58 
Irritating gases, 2, 199 
K 
Klaxon horn, 39 
Kops-Tissot mask, 37 
L 
Laboratory section, 8 
Lachrymators, 3, 4, 40, 44, 57, 
117, 124, 219, 220, 221 
Lachromatory bombs, 6 
Lachoramatory gases, 199, 
200 
Lethal gases, 58, 68, 212 
Lethal substances, 1, 3 
Lenses, 31 
Liaison, 150, 152, 161 
Livens drums, 144, 146 
Livens material, 125, 126 
Livens projectors, 7, II, 115, 
125, 142, 146, 151 
M 
Map and intelligence assist- 
ant, 130 
Masks, 22, 27, 28, 29, 31, 32, 
34, 37, 38, 51, 58 
Master engineers, 130 
Meteorology, 163, 164 
Methods of projection, 114, 
115, 126 
Military assistant, 131 
Mills pistol head, 141 
Mustard gas, 4, 5, 10, 15, 21, 
23, 26, 41, 42, 44, 45, 46, 
47, 66, 71, 114, 117, 120, 
122, 123, 124, 200, 222, 223, 
224, 225, 226 
Mustard gas plants, 12, 15, 16 
N 
National research council, 2, 
10 252 
INDEX 
Neutralizing fire, 57, 58 
Neutralizing substances, I, 3 
Nitrous fumes, 219, 220, 221 
Noise bombs, 6 
Non-persistent gases, 58, 68, 
199 
Noxious gases, 1, 10, 11 
O 
Oleum, 7 
Organization of an attack, 
163 
Oxygen breathing apparatus, 
2, 166, 168 
P 
Parazol, 7 
Percussion fuses, 78 
Persistency of gases, 41, 114, 
115, 116, 117, 123 
Persistent gases, 68, 70, 199 
Phenylchlorarsine, 10 
Phosgene, 9, 19, 20, 23, 24, 
26, 41, 42, 44, 46, 114, 117, 
120, 121, 199, 200, 201, 212, 
213, 214, 215, 216, 217, 218 
Phosgene plants, 12, 20 
Phosphorous, 7, II, 93, 118 
Phosphorous hand grenades, 
100, 109 
Phosphorous shell, 62 
Physical constants, 10 
Picric acid, 19 
Platoon leader, 136, 149 
Poison gas, 2 
Poisonous weapons, 13 
Primers, 9 
Projector attacks, 227, 229 
Projectors, 142, 143 
Propellants, 125 
Protection of tanks, 93 
R 
Ranging bomb, 139 
Ranging gas shells, 75, 77 
Regimental gas officers, 174, 
178, 180, 181 
Regimental supply officer, 
129 
Rescue apparatus, I 
Research work, 1, 2, 3, 4, 5 
Respirator drills, 188, 189, 
190, 191, 192 
Respirators, 28, 39, 63, 184, 
185, 188, 193, 194 
Respirators for horses, 184, 
193 
Rifle grenades, 107, 108, 109, 
1*5 
Runner service, 164 
S 
Sag paste, 39, 225 
School phase, 158 
Second in command, 134 
Selenocyanides, 10 
Semi-persistent gases, 68, 69 
Service of security and in- 
formation, 152, 162 
Shell markings, 74, 75, 83, 84, 
85, 86, 87, 88, 89, 90, 91 
Shells, 6 
Signal-light section, 8 
Silicon tetrachloride, 7, 9 
Skin blisters, 45 
Smoke, 9, 61, 77, 93, 94, 95, 
96, 97, 118, 152, 153, 154, 
203 
Smoke barrage, 93 
Smoke bombs, 6, 100, 125, 138, 
139, 166 
Smoke cage, 99 
Smoke candles, 9, 60, 100, no, 
in, 112, 115 
Smoke clouds, 60 
Smoke grenades, ioo, 15 
Smoke screens, 2, 6, 53, 60, 
93, 95, 96, 98, 112 
Smoke shell, 53, 60, 61, 62, 
68, 75, 81, 93, 99 
Smoke torch, Mark I, 112 INDEX 
253 
Sneezing gas, 3, 5, 199 
Sodium permanganate, 36 
Special equipment assistant, 
131 
Spray painting plants, 12 
Stability of gases, 10 
Stabilized warfare, 153 
Stannic chloride, 46 
Stannic tetrachloride, 9 
Steel gas shell, 84, 85, 86, 87, 
88, 89, 90, 91, 92 
Stermutators, 3, 4 
Stokes mortars, 115, 125, 126, 
136, 138, 151, 154 
Stokes smoke bombs, 94, 100, 
113 
Suffocante et lachrymogene 
hand grenade, 102 
Suffocating gases, 12 
Sulphur monochloride, 21, 22 
Superpalite, 9, 46, 201 
Super-quick fuses, 79, 80, 81 
Supply assistant, 131 
Sutton fuse, 142 
T 
Tear gases, 3, 5, 6, 22, 23 
Tear producers, 44, 46 
Tetrachlorides, 93, 118 
Thermite, II, 152 
Thermit hand grenade, 100, 
101 
Thirty-one D fuse, 141 
Tin tetrachloride, 26 
Tissot mask, 31, 37 
Tissot respirator, 184, 185 
Titanium tetrachloride, 9, 60 
T. N. T., 7 
Toluol, 23 
Toxic gases, 12, 13, 14, 38 
Toxicity tests, 1, 5 
Toxic smoke producers, 42 
Toxic substances, 6, 43 
Training assistant, 130 
Training of gas troops, 156, 
159, 160, 161, 163 
Training of special detach- 
ments, 152 
Training smoke bombs, 106, 
172, 173 
Transportation assistant, 131 
Trench fans, 39 
Trench projectors, 2 
Trichlormethyl-chlor formate, 
201 
Triplex glass, 30 
Tyndall meter, 9 
V 
Vapor pressures, 10 
Vesicants, 45, 81 
Vincennite, 47 
W 
Warfare gases, 199 
Warfare gas investigation, 1 
Warning devices, 39 
White phosphorous, 26, 60, 
77, 118 
Wind, 50, 51, 55, 61, 120, 121, 
183 
Wing-tip flares, 167 
W. P. shell, 60, 77 
Y 
Yellow cross gas, 222 
Yperite, 46, 222