EPIDEMICS OF THE CENTURY, 
AND THE 
LESSONS DERIVED FROM THEM 
BY 
GrOUVERNEUR M. SMITH, M. D., 
VICE-PRESIDENT OF THE NEW YORK ACADEMY OF MEDICINE ; PHYSICIAN TO THE NEW 
YORK AND TO THE PRESBYTERIAN HOSPITALS, ETC. 
[.REPRINTED FROM THE TRANSACTIONS OF THE NEW YORK 
ACADEMY OF MEDICINE.-] 
UNA FIDES ALTARE COMMUNE. 
NEW YORK: 
D. APPLETON & COMPANY, 
5 49 & 551 BROADWAY. 
1876. EPIDEMICS OF THE CENTURY, 
AND Tim 
LESSONS DERIVED FROM THEM. 
h j 
v S' 
GOUVERNEUR M. SMITH, M. D., 
VICE-PRESIDENT OP THE NEW YORK ACADEMY OP MEDICINE; PHYSICIAN TO THE NEW 
YORK AND TO THE PRESBYTERIAN HOSPITALS, ETC. 
[REPRINTED FROM THE TRANSACTIONS OF THE NEW YORK 
ACADEMY OF MEDICINE.} 
UNA PIDE8 ALT ARE COMMUNE. 
NEW YORK: 
D. APPLETON & COMPANY, 
549 & 551 BROADWAY. 
1876. EPIDEMICS OF THE CENTURY, AND THE LESSONS DE- 
RIVED FROM THEM. 
By GOUVERNEUR M. SMITH, M. D., 
▼ ICE-PRESIDENT OF THE NEW YORK ACADEMY OF MEDICINE, PHYSICIAN TO THE NEW 
YORK AND TO THE PRESBYTERIAN HOSPITALS, ETC. 
Read May 4, 1876. 
Civilization of modern times makes rapid progress, and 
a consideration of its yearly advancement and of the diseases 
incident thereto is a prolific subject of study. 
In the review which is being taken by this Academy of 
the progress of medical science during the century of our 
national existence, the department of epidemics has been as- 
signed to me for presentation on this occasion. The limits of 
a single discourse will admit only of a mere glance at this im- 
portant topic, but the glance will be sufficient to show the 
industry and the success of our profession in elucidating the 
causes and in improving the management of those pestilen- 
tial disorders which have appeared within our territory. 
The period of review begins with the year 1776 and ends 
with the present year, 1876—a century peculiarly interesting to 
the American people, and pregnant with events which have 
moulded and which are still to mould the destinies of the 
world. 
If we look across the ocean at the beginning of this period 
we find the indefatigable John Howard, of England, in the 
prime of life exploring the adyta of penal institutions and en- 
deavoring to improve the morals and health of their inmates. 
At a later time, viz., in 1790, we find him fifteen hundred 
miles from home and, while pursuing his philanthropic duties, 4 
dying in Russian Tartary. Princes, admirals, generals, magis- 
trates and peasants united in paying him funeral honors—the 
land of the czars unheeding the fact that plebeian blood had 
nourished his royal heart. In the cathedral and valhalla of 
St. Paul in his native land can be read this description: lie 
expired “ a victim to the perilous and benevolent attempt to 
ascertain the cause of and find an efficient remedy for the 
plague. He trod an open but unfrequented path to immor- 
tality in the ardent but unintermitted exercise of Christian 
charity.” 
His biographer informs us that “ His death fell on the mind 
of Europe like an ominous shadow : the melancholy wail of 
grief which arose on the Dnieper was echoed from the Thames 
and soon reechoed from the Tagus and the Neva and the Dar- 
danelles.” No allusion is made to the effect which was pro- 
duced on the shores of the mighty Hudson of the young Amer- 
ican republic—the hum of a busy civilization was scarcely 
then audible on its thinly populated banks and the republic 
had scarcely assumed a recognized position in the brotherhood 
of nations. But our forefathers, imbued with advanced ideas 
of political and religious liberty, and differing in opinion from 
the nations of the Old World on these topics, were neverthe- 
less ready to adopt the tenets of transatlantic philanthropy if 
originating either in the ages of a near or a remote antiquity 
or among contemporaneous peoples with whose political 
teachings they were at variance. 
Nothing can better illustrate the American medical spirit 
of the period to which allusion is made than a glance at the 
brief but brilliant life of Dr. Elihu II. Smith. History de- 
mands a recognition of his useful career : I know not if a rela- 
tive survives him. 
Born in Litchfield, Conn., in 1771, he ripened into man- 
hood at a time when IIowTard was prosecuting his benevolent 
work in Europe, and was but nineteen years of age at the 
time of Howard’s decease. Settling as a young physician in 
New York, he was appointed physician to the New York 
Hospital, and became associated in 1798 with Dr. Samuel L. 5 
Mitchell and Dr. Edward Miller in editing The Medical 
Repository, which was the first American medical periodi- 
cal published in this country. The first paper in the first 
number of this journal was from the pen of Dr. Smith, and 
was entitled “ The Plague of Athens.” This classical essay 
can be read with profit at the present day. 
The statesmen of that period were using their best exer- 
tions to strengthen the resources of the republic ; the phy- 
sicians with no less patriotism were endeavoring to shield the 
country from those pestilential besoms which in the Old World 
had so often inspired terror and induced desolation. 
Dr. S., in concluding his paper, said: “If local causes 
originated a pestilence in Athens, local causes may generate 
a yellow fever in Philadelphia and New York. To these, 
then, be our attention more scrupulously directed, and let us 
be more solicitous in the inspection of our houses, yards, 
streets, and docks, than in that of cottons and woolens of ves- 
sels from the West Indies and ships from the Mediterranean.” 
Unfortunately for science, in the very year in which this 
paper was published, viz., 1798, Dr. S., while in his twenty- 
seventh year was smitten, in September, with yellow fever, 
then disastrously prevailing in this city, and closed his career. 
The Medical Repository, in announcing his decease, 
says: “As a physician his loss is irreparable. He had ex- 
plored at his early age an extent of medical learning for which 
the longest lives are seldom found sufficient; . . .he was 
ripe for the highest honors of his profession, his merits were 
every day becoming more conspicuous, and nothing but his 
premature fall deprived him of that extraordinary degree of 
public confidence which awaited a longer continuance of his 
life.” 
In the second volume of the periodical before mentioned 
is found a posthumous paper of Dr. S. “ On the Pestilential 
Diseases which at Different Times appeared in the Athenian, 
Carthaginian, and Human Armies in the Neighborhood of 
Syracuse.” 
Allusion has thus early been made to the labors of Dr. 6 
S., whose career commenced with the century ; and the efforts 
of others might, have been cited with like propriety, in order 
to remind us that while the fires of genius are now burning 
brightly on our altars, they were not kindled by those who 
are within our personal recollection, but were ignited by those 
whose lives were identified with the early period of our na- 
tional existence. The fact is also illustrated that then, as 
wrell as now, youthful enthusiasm helped to develop and to 
mould medical philosophy. 
It would be unbecoming on an occasion like the present 
to give the details of the various epidemics which have visited 
our territory ; it must suffice to group their general features 
and to evoke therefrom general deductions. Monuments to 
each pestilential visitation are thickly found in medical liter- 
ature, and the explorer of to-day has merely to read their 
inscription to learn of their desolations, and to find not un- 
frequently the interment of various theories regarding the 
etiology and management of occult morbific influences. 
In investigating our subject it will be found that several 
disorders which formerly were chiefly feared on account ot 
their periodical general appearance have bequeathed to us 
venoms which have become naturalized in our midst, and 
which, though constantly and to a certain extent disastrously 
operative, are nevertheless prevented from exercising a very 
general pernicious influence by reason of the enforced san- 
itary regulations respecting them. 
Our immediate territory is so far remote from the tropics 
that it can scarcely harbor and foster, for a long season at 
least, miasmata which are peculiar to the equatorial region 
of the earth. Nevertheless, we have a climatic season in 
which, by reason of the high temperature, if southern poisons 
are introduced, they may assume in our midst a pestilential 
character. Indeed, the ordinary maladies of our summer cor- 
respond in their nature with those which are observed in 
torrid situations, but are fortunately of less gravity. 
Nations of the earth, in order to be regarded as mighty 
powers, must acquire a typical strength—such strength being 7 
shown in the ability they possess for self-preservation. They 
must possess a force sufficiently vigorous to control their in- 
ternal political and disturbing influences, and likewise a force 
capable of arresting the inroads of invading neighbors. 
The inhabitants of the northern temperate zone—a zone 
recognized as the one in which man attains his highest mental 
and physical development, and the one in which our lot is 
cast—the inhabitants, I say, of this zone, being favored by 
natural causes, and by the advances of civilization, should feel 
it obligatory upon them to protect themselves not only from 
internal causes of disease, but also from the encroachments of 
inimical morbific influences from other zones, nations, and 
localities. Here intelligence and wealth, the resources of 
science, and the benevolent operations of religion, can best 
unite to develop manhood. 
It can be clearly demonstrated that we of the present day, 
by reason of the advancement and diffusion of scientific 
knowledge, are better fitted than were our forefathers of a 
century ago to cope with various noxious agencies. Commu- 
nities are not so readily panic-stricken as formerly at any 
threatened approach of pestilential diseases, being less super- 
stitious and having more faith than formerly in artificial 
counteracting influences. 
New sources of disease are developed by civilization—new 
measures of prophylaxis germinate simultaneously with each 
genesis. Many of the poisons with which we are familiar, 
and which were known to our ancestors, are not as yet to be 
extinguished, but are to continue to harass posterity. Pos- 
terity will encounter ills which have not afflicted us, and the 
medical literature of future centuries will relate the outcrops 
of novel disorders, and record the successful means by "which 
they were held in abeyance. If the chemists are capable of 
producing new compounds, it can be inferred by analogy, and 
even inferred from a study of past ages, that in the mutations 
of society new forms of aerial contaminations and new zymotic 
affections will be developed by reason of the overcrowdings of 
population, by the influences of new occupations and of new 8 
relations of life. The opening of new territories to civiliza- 
tion will be attended with its dangers. Indigenous germs of 
disease may exist in unexplored Africa and in other secluded 
parts of the globe, which are in time to be conveyed to marts of 
commerce, and thence to be still more widely diffused. 
These prefatory and textual remarks lead us to a consid- 
eration of the epidemics which have chiefly excited interest. 
The disorders which have thus appeared have been vari- 
ously grouped. In the nosologies which have been accepted 
during the century, commencing with the one of Vogel in 
1772, and subsequently in those of S:\gar, Macbride, Cullen, 
Darwin, Crichton, Piriel, Parr, Young, Good, Ilosack, and in 
the one adopted by our present Board of Health, as recom- 
mended by the International Statistical Congress, we find 
that the diseases under consideration have been classified in 
diverse manners, such variations being made to adapt the 
grouping to modified medical views respecting the etiology of 
the maladies. 
The late Dr. Joseph M. Smith, in his “ Report on the 
Medical Topography and Epidemics of the State of New 
York,” submitted to the American Medical Association at its 
annual meeting in June, 1S60, in writing on this subject, 
remarked: “ Distributed according to their natural affinities 
or etiological relations, epidemics are reducible to three kinds, 
viz., contagious, infectious, and meteoratious. These terms 
are here employed in the sense they are used in the writer’s 
work on the ‘Elements of the Etiology and Philosophy of 
Epidemics.’ ”1 
In such grouping, under the contagious epidemics were 
placed, small-pox, measles, scarlatina, and, as minor affections, 
varioloid and varicella; under the infectious, intermittent and 
remittent fevers, dysentery, yellow-fever, typhus, and com- 
pound fevers; under the meteoratious, influenza, typhoid 
pneumonia, diphtheria, erysipelas, and Asiatic cholera. 
This classification, at the time, appeared as concise and as 
’“Transactions of the American Medical Association,” vol. xiii., 
1860, p. 175. 9 
accurate as it could possibly be made with the current scien- 
tific data. During the last decennary, the powers of the mi- 
croscope as an instrument of etiological investigation have 
greatly increased, the spectroscope has developed new meth- 
ods of inquiry, and experts have been in conference collecting 
observations and collating facts. 
To say nothing at present of the careful study given to other 
epidemic disorders, what special attention has been given to 
cholera! An International Sanitary Conference, convened at 
the instance of- the Austro-Hungarian Government, held at 
Vienna in 1874, devoted an entire month to a study of this 
malady. At the conference, Persia, Egypt, and every Euro- 
pean state, were represented—an assemblage of delegates repre- 
senting twenty-two nationalities. It is not a matter of sur- 
prise that, as a result of such advanced studies of epidemics, 
views concerning some of them have been modified. 
Medical philosophy is now grasping after material or 
appreciable causes to explain morbid phenomena—theories, 
though admissible to investigation, must be sustained by ob- 
servations which can, in part at least, be practically demon- 
strated by the chemists and microscopists. 
I shall subsequently refer to the labor which has been 
expended upon the study of minute vegetable organisms and 
entozoa as causes of diseases. At present it must suffice to 
allude to the former of these. 
There are so-called filth-diseases, as appropriately de- 
nominated by Mr. John Simon. Excrementitious material 
from animal organisms, the refuse of households, factories, 
etc., either in rural or in city localities, may become causes of 
disease if not properly disposed of. Such excrement can 
largely be utilized to promote the welfare of the state in its 
agricultural interests, but, instead of its being thus employed 
or being rendered innocuous, it is constantly operative as a 
cause of disease and death. 
These debris may become poisonous in a twofold manner: 
1. They are liable to decomposition, and the inorganic gases 
thus developed, unless under circumstances permitting their 10 
free diffusion, are injurious to those respiring them. Their 
effect, however, upon the animal economy is comparatively 
slight, and, the gases being merely inorganic, chemical com- 
pounds have no power of self-multiplication to induce further 
mischief beyond the persons of those who have inhaled them. 
2. The debris alluded to are a fertile soil for the growth 
of noxious minute vegetable organisms. The refuse, if wisely 
distributed over glebes, rewards the laborer with turf teeming 
with cereals and rich in its production of edible vegetation ; 
but, unwisely hoarded, this same material fosters the most 
luxuriant growth of innumerable microscopic vegetative 
growths, which bodies, being organic in their nature, pos- 
sess the power of reproduction to an indefinite extent, even 
in other localities than those in which their development is 
specially favored. Sume of these growths are believed to 
possess properties as conspicuously poisonous to mankind 
when gaining access to ‘the system through the air, food, or 
wTater, as are the well-recognized benign influences upon the 
economy of the fruits of meadows and table-lands. 
In the study of plants of the lower grade, Klein is asserted 
to have discovered the microphyte of enteric fever. In cholera, 
scarlet fever, diphtheria, vegetable growths have been ob- 
served, and, in various diseases, the excreta from the bowels, 
etc., are supposed to contain the germs of the prevalent mor- 
bid infections. 
Vegetation, indeed, induces disease in vegetation. The 
Scripture says, “ I smote you with blasting and mildew.” 
“ Blasting” and “ mildew” have scourged the crops of the an- 
cient Jews and Romans. The modern farmer employs the 
terms smut, Imnt, rust, and mildew, to describe the more com- 
mon diseases of vegetation, and, on a former occasion, as I 
have said before this Academy, these conditions are induced 
by vegetable parasites. Not a plant cultivated by man is free 
from such fungi. In the recent investigation of disease, as 
affecting the inferior animals and man, similar growths are 
believed to play an important part in their production. 
But, while admitting such to be the case, there are doubt- 11 
less other cooperative factors favoring the spread of epidemic 
disorders. There are atmospherical states which exert potent 
influences in promoting the diffusion of maladies. Those 
which are readily recognized, such as relate to heat, cold, 
moisture, dryness, electricity, calm, winds, etc., are observed 
to affect intensities of prevalence. As respects electricity, 
we appreciate the deadly result of the shaft of lightning— 
are there not obscure influences of this principle at times 
operative, concerning which we are unaware? The atmos- 
phere is never in a state of stable electrical equilibrium, and 
it is unphilosophical to suppose that varying electrical con- 
ditions exert no influence, directly or indirectly, upon ani- 
mate nature. 
Respecting ozone, that mysterious, active, and condensed 
form of oxygen, how comparatively little is known as regards 
its general effects! Its presence in the air varies with the 
time of day and with the prevalence of certain winds, and is 
less appreciable in over-crowrded localities than in uninhabited 
or sparsely-settled regions. We recognize it as the great oxi- 
dizing and purifying agent—an agent which is readily meta- 
morphosed, for while speeding in its noble mission of reforma- 
tion, and while in the act of purification, it*is transmuted into 
the simpler form of oxygen. 
Ozone, when undiluted, is irrespirable, and, when but mod- 
erately diluted, oxidizes the blood unnaturally and induces 
pulmonary irritation and systemic disturbance. It is readily 
inferred that, when this principle is present in a compara- 
tively small quantity in the atmosphere, those respiring it are 
not thereby sufficiently vitalized, and that local mephitic 
agencies, bereft of a counteracting influence, acquire aug- 
mented morbific powers. When this same principle occurs 
excessively in the air, there is every reason to believe that 
other morbid phenomena are induced. More precise knowl- 
edge concerning this principle is needed, as well as of other 
principles of whose presence in the atmosphere \\A are already 
aware. 
Is there not an “ epidemic meteoration,” or condition 12 
which comprehends “insensible qualities of the general at- 
mosphere, which produce or favor the prevalence of popular 
diseases?”1 Investigations in this direction have not, as yet, 
been fully made. We have not, as yet, been famished with 
instruments or means of inquiry sufficiently accurate to de- 
cipher occult influences of the atmosphere, and such an inquiry 
is essential, if we are to fully understand the wide-spread ap- 
pearances of disease. 
Water impregnated with certain organic and inorganic 
material is inimical to health; the atmosphere similarly con- 
taminated is similarly noxious. The air is more complex in 
its chemical nature than water, and is, consequently, liable to 
greater vicissitudes in composition, and its principles, not all 
being chemioally combined together, may be capable of be- 
having, under peculiar circumstances, in a mysterious way 
upon mankind. There is not that same stable constitution in 
air as there is in water jper se. 
While diffusion in the atmosphere prevents a universal 
and dangerous contamination from local pernicious causes, 
nevertheless, combined aerial and terrene conditions may ren- 
der considerable regions of territory insalutary. A disease 
may be contagious through excreted germs, but for the disease 
to spread over extended areas the germ and atmosphere must 
be coadjutors ; in other words, the germ must find a congenial 
medium in which either to sustain its life or to promote its 
growth, multiplication, and diffusion. It is, doubtless, true 
that the air at times is a mere vehicle of morbid germs, and 
such germs, when meeting congenial terrene or systemic con- 
ditions, there fructify, as the seeds of grass, etc., may be wafted 
by winds to develop in distant and fruitful soils. 
Points of investigation specially needing elucidation at 
present are these: To what extent are meteoratious conditions 
alone responsible in the production of disease? To what ex- 
tent are morbid germs culpable? What aerial conditions 
essentially favor germ diffusion ? To what degree are inor- 
1 See “Elements of the Etiology an<l Philosophy of Epidemics,” by 
Joseph Mather Smith, M. D., New York, 1824, p. 115. 13 
ganic mephitic influences operative in the causation of dis- 
ease? 
Another point of interest relating to etiology is an inquiry 
into the nature of the development of a contagious element in 
the course of certain inflammatory diseases, and into the pro- 
cesses by which a multiplication of infectious germs takes place 
within the animal economy, irrespective of vegetative growth. 
Puerperal fever occasionally seems to occur, even when the 
patient is under the most auspicious circumstances, and when 
there has been no appreciable inoculation with the disease, 
and from such a case contagion may arise and be diffused. It 
is common to attribute such a febrile genesis to a poison gen- 
erated within the uterus, from decaying clots, portions of pla- 
centa, etc., which is absorbed into the system. 
It has not been easy to explain the multiplication of the 
poison—the spread of the disorder. May it not be accounted 
for in this way ? If innumerable bioplasts are eliminated from 
such a patient, is it not presumable that these minute organic 
particles are impregnated with the poison derived from the 
patient, and that they may become morbific germs ? Indeed, 
the idea is now becoming prevalent that a number of diseases 
are contagious which have never been supposed to possess any 
such attribute. The method of their diffusion has not been 
clearly understood—infected bioplasts may be the morbid 
vehicles. 
Vegetative growths may induce certain diseases, and spe- 
cific poisons may thus he engendered in the animal economy. 
Hioplasts may be instrumental in spreading such septic con- 
ditions, and thus compound causes may cooperate in diffusing 
various maladies. 
From what has been said it is evident that, concerning the 
specific natures of the poisons of a number of the epidemic 
disorders, we are almost entirely ignorant. We regret to 
have to acknowledge such ignorance, but have an ample 
cause of excuse. Some of these causes have been operative, 
at intervals at least, from time immemorial. But while this 
is a recognized fact, nevertheless, human genius has only been 14 
qualified within a comparatively short time to engage in 
studies of such a nature. If we regard merely the eighteen 
centuries and three-quarters of a century of time according to 
our present computation of years, we can eliminate nearly 
eighteen centuries during which progress in such direction 
was at all practicable. We have scarcely to look back a 
decade of decades to find chemistry developing as a branch 
of scientific inquiry. We find hydrogen, oxygen, and nitro- 
gen, and various other elements, shining out more brightly as 
the chemical discoveries of the century than the new lights of 
Uranus and Neptune in the contemporaneous centenary of 
astronomy. With the genesis of chemistry new philosophical 
attributes were unfolded to man, and with gradually-acquired 
gifts of analysis and synthesis, of eduction and production, 
he has clearly defined the operations of various occult atomic 
affinities, and is engaged in the definition of numerous mys- 
terious phenomena of nature and of art. The microscope 
and spectroscope promise very material guidance in further 
researches, but as yet have afforded imperfect information, 
but the information already afforded has almost revolutionized 
medical philosophy relating to the subjects under considera- 
tion. While we deplore our ignorance concerning the precise 
natures of the poisons to which allusion has been made, we 
feel assured lux lucet in tenebris, and furthermore feel con- 
scious, as the sequal will show, that we are already armed, 
through the resources of hygiene and chemistry, with means 
which have shorn pestilential disorders of half of their ter- 
rors. 
We have found, in examining the etiological branch of our 
subject, that there are several paths of inquiry which have 
only been partially explored. With a limited knowledge in 
regard to vegetable parasites, and other organic germs, as 
causes of disease, and with a very limited acquaintance with 
the nature of atmospherical vicissitudes as inducing morbid 
conditions, with studies on these subjects at present being 
very intently prosecuted, it seems more difficult at this time 
to make a new nosological grouping of epidemics than it has 15 
ever been before. We appear to be on the very threshold of 
developments which are probably to modify many of our 
preconceived ideas. Such being the case, I will not to-night 
attempt any new classification of diseases, but in treating of 
the disorders which have appeared as epidemics in our terri- 
tory, as a matter of convenience, will merely speak ot them 
in the order in which they have before been enumerated. 
I will first consider the lessons which have been taught us 
by the visitations of small-pox, measles, scarlatina, and vari- 
cella, usually classified among the contagious disorders. As 
prefatory to such consideration it is desirable to say a few 
words in regard to murrains and ejpizodties, which from time 
to time have prevailed, for between these diseases and epi- 
demics there is often a close relationship, though not neces- 
sarily so, but it is particularly a noticeable occurrence be- 
tween cow-pox and small-pox. 
The prevalence of murrains has been recognized since a 
remote antiquity. In sacred history, Moses records, “ Behold, 
the hand of the Lord is upon thy cattle which is in the field, 
upon the horses, upon the asses, upon the camels, upon the 
oxen, and upon the sheep: there shall be a very grievous 
murrain ” (Exodus, ix. 3); and he further has described the 
disorder as “a boil breaking forth with blains upon man and 
upon beast” (Exodus, ix. 10). Profane history abounds in 
allusion to epizooties. Homer in his “ Iliad ” relates : 
“ On njules and dogs the infection first began, 
And last the vengeful arrows fixed in man.” 
In CEdipus is read : 
“ For all those plagues which earth and air had brooded, 
First on inferior creatures tried their force, 
And last they seized on man.” 
It is unnecessary to multiply allusions to the numerous 
epizooties which have prevailed in the world’s history. The 
causes of these are in many cases as inexplicable as are those 
of some of the epidemics, but are being studied with interest 
and with most promising results. Those which have most re- 16 
cently been observed in our territory have not appeared to 
have an intimate connection with human maladies, though in 
1825 a disorder among horses, known as slavers, Vnade a disas- 
trous visitation, and preceded an epidemic of erysipelas and 
influenza throughout a part of this State. 
It was a study of the relationship between vaccinia and 
variola, made about the commencement of this century, which 
led to the discovery of the great prophylactic of small-pox, viz., 
vaccination. Cow-pox made its appearance in England in 
1745, and subsequently in 1770, when, as recorded by Aitken, 
“ it appeared among the horned cattle with so much severity 
that his majesty George III., in his speech from the throne, 
at the opening of Parliament, on the 9th of January of that 
year, called upon the Houses of Parliament to take the sub- 
ject into their serious consideration. The disease continued 
with more or less violence till 1780, and it was no doubt the 
expiring embers of this epizooty which Dr. Jenner found in 
Gloucester, and made the basis of his investigation during 
that and subsequent years.” In 1798, Jenner promulgated 
the result of his study in this direction. The medical profes- 
sion of the civilized world has substantially adopted his views, 
and his name has almost been enshrined with that of Aescu- 
lapius. 
It has not been an easy task to educate the popular mind 
into a belief in the prophylactic powers of vaccination, but 
three-quarters of a century have sufficed to accomplish the 
important work. With proper care, epidemics of small-pox 
can now be absolutely prevented, and when from neglect the 
disorder is encountered the patient need no longer be avoided 
by kindred and who have been properly protected. 
Certainly the century under consideration marks in this re- 
spect an epoch in medical history, and American physicians 
have been foremost in experimenting with and in advocating 
inoculation, and subsequently vaccination, as a means of pre- 
venting one of the most loathsome of human disorders. 
Respecting the other contagious epidemics, viz., of scarlet 
fever, measles, and chicken-pox, the latter is ordinarily such 17 
a mild affection as to require only passing notice. Of the 
others we unfortunately cannot speak so encouragingly as 
can be done of variola. Both prevail at times in an epidemic 
manner, their diffusion being favored by some unknown 
and peculiar condition of the atmosphere. This condition is 
not identical with that which propagates the meteoratious 
diseases, for there is not generally a contemporaneous preva- 
lence of both classes of maladies. The poison of these 
maladies when once introduced, especially in the larger 
villages and in cities, appears hardly ever to be entirely erad- 
icated. 
Now, while we cannot boast of any special means of pro- 
phylaxis, we nevertheless find that a long series of years will 
elapse without an extended appearance of the diseases under 
consideration. This phenomenon can be accounted for in two 
ways: 1. Atmospheric influences do not always favor their 
diffusion. 2. When their diffusion is thus favored, increased 
vigor is employed in checking their spread. For example, 
the apartment of the isolated patient is thoroughly venti- 
lated, and the poison, in only an attenuated form, can be 
wafted from the chamber or scattered by fomites. The re- 
moval of carpets and unnecessary furniture to prevent their 
infection, disinfection of the air, of the excreta, of the clothing, 
and destruction of some of the latter by fire, and, finally, 
fumigation of the apartment, are some of the means now re- 
sorted to with undoubted success to stay the progress of the 
disorder. 
Among intelligent physicians these or kindred measures 
are voluntarily enforced to prevent the multiplication of foci 
of disease, and many municipalities enjoin such sanitary pre- 
cautions. Prophylaxis in this direction has certainly made 
progress with the advance of time. 
We now come to a consideration of another group of affec- 
tions, viz., typhus and typhoid fevers, malarial affections, in- 
cluding dysentery and yellow fever, which have been classified 
as infectious epidemics. Typhus and typhoid fevers have an 
element in their character which allies them to a certain ex- 18 
tent with the contagious disorders; the same remark is also 
applicable to dysentery, though perhaps in a more limited 
degree. A poison is disseminated from each patient suffering 
from these maladies, and those exposed while in attendance 
upon such patients are liable to become infected ; but, in ad- 
dition thereto, there appears to be a more or less diffused 
aerial condition favoring the diffusion of the diseases alluded 
to. Overcrowding of tenements, imperfect ventilation, de- 
fective trapping of waste-pipes, and faulty drainage, favor the 
local spread of the disorders, and the soil, becoming impreg- 
nated wTith morbific material, renders the water used as drink 
a vehicle of disease. From one or more of these causes have 
appeared at various times outbursts of the disorders under 
consideration in jails, ships, camps, villages, towns, and in 
scattered hamlets and rural situations. Armies, as is well 
known, have rendered the localities in which they were tarry- 
ing pestilential in the extreme, and on breaking up their quar- 
ters have by fomites carried with them devastation along the 
line of their march. But modern sanitary science lias eradi- 
cated or modified many causes which in war, ocean-travel, 
penal and eleemosynary institutions, and among mankind gen- 
erally, in segregated and gregarious life, have favored the de- 
velopment and spread of the febrile affections under considera- 
tion. 
Respecting the malarial affections, our territory is so for- 
tunately situated as not to develop those severe types charac- 
teristic of the same class of maladies encountered in the tropics. 
Intermittent and remittent fevers and dysentery are diseases, 
however, of sufficient gravity to intimidate the residents of 
regions in which they prevail. The prevalence of these dis- 
orders in distinctive paludal and littoral situations has left no 
doubt in regard to their etiology, though the precise nature of 
the miasm engendered in such places has never been abso 
lately defined. 
On a former occasion I have shown that the Pontine 
Marshes spread infection in the territory of the Volschi, as 
they contaminate the same tract of country for its modern 19 
inhabitants.1 But the Italian morass, thirty miles in length 
and eight in breadth, has at times been partially converted 
into inoffensive and fertile plains by the thorough system of 
drainage enforced during the reigns of Augustus, Nerva, and 
Trajan, and during the pontificate of Pius YI. At other pe- 
riods engineering resources were neglected ; rich fields de- 
generated into impassable and noisome bogs, while the in- 
habitants of the environs lost their ruddiness and acquired an 
anaemic pallor. 
Had the efforts toward reclamation been persistently made 
from the time of their inception by the consul Cethegus, a 
baneful spot could have been permanently obliterated ; stag- 
nant waters could have been collected into running streams, 
quagmire converted into loam, and the low vegetation of a 
vast fen metamorphosed into genial fruitfulness. The earth 
itself would have become as magnificent a monument of the 
philosophy and grandeur of ancient Roman civilization as 
have been the classical literature and massive architecture of 
the historical period alluded to. 
In modern times there have been imitations of the ancient 
methods of drainage, in numerous localities, and with the 
most satisfactory results, but, while we find it practicable to 
improve the health of certain localities by the means indi- 
cated, it seems to us at present almost a fruitless task to at- 
tempt to reclaim a large part of an entire continent by means 
of such sanitary engineering skill. To escape injury from ir- 
remediable regional morbific influences, the inhabitants must 
invoke the resources of private hygiene and establish physical 
vigor capable of withstanding baneful surroundings. 
In regard to yellow fever, we find its poison engendered 
and most intensified under the equatorial sun—in a zone 
where vegetation is monarch, and where aboriginal man, ener- 
vated and to a great degree secluded by reason of climatic 
causes, as regards his highest attributes, is no more typical of 
manhood than vegetation is typical as found on mountain 
1 Anniversary Discourse, New York Academy of Medicine, Gouverneur 
M. Smith, 1870. 20 
eminence or in polar latitude. The poison, however, diffuses 
itself over semi-tropical regions, and is conveyed to the tem- 
perate zone, and here, during the summer solstice, especially 
if favored by a hot and humid atmosphere and insalutary lo- 
cal conditions, it can for a season operate disastrously. But 
the resources of science step in to arrest its operations. Ex- 
perience has taught that wisely-administered quarantine regu- 
lations, conjoined with local sanitary precautions, can either 
blockade its entrance into northern ports, of at least deprive 
it of resources favoring its epidemic diffusion. In corrobora- 
tion of this fact, we have simply to study the frequent threat- 
ened invasions of the port of New York, and of various cities 
on our southern seaboard, and specially the sanitary history 
of New Orleans during our recent war. 
Respecting the latter subject, our distinguished Fellow, Dr. 
Elisha Harris, in a paper read before this Academy, January, 
1865, on “ Hygienic Experience in New Orleans during the 
War,” etc., appropriately said : “ Such immunity from her 
accustomed scourging of yellow fever had not been enjoyed by 
New Orleans the last half century. Even her wisest hygien- 
ists had been generally discredited, and often derided, when 
they publicly taught, as Fenner, Barton, Sitnonds, and Ben- 
nett Dowler had most faithfully, that the active and localizing 
causes of yellow fever, and the high death-rate in that city, 
were preventable. There was a truthfulness worthy of the 
medical profession in the words of Dr. Barton, who, as presi- 
dent of the New Orleans Sanitary Commission, sitting in 
grave and scientific consultation upon the terrible visitations 
of yellow fever, unhesitatingly declared the causes of that 
pestilence and the city’s excessive insalubrity ‘ entirely suscep- 
tible of cure? But how few persons appreciated the truth of 
Dr. Barton’s words of prophecy, when he said that ‘ upon the 
broad foundation of sanitary measures we can erect a monu- 
ment of public health, and,that if a beacon-light be erected on 
its top, and kept alive by proper attention, this city will be 
second to none in this first of earthly blessings! ’”1 
1 “Bulletin New York Academy of Medicine,” No. 30, September, 1865. 21 
1 come now to consider a group of affections varying 
greatly in their character, as regards both the severity and 
the nature of their symptoms. I allude to influenza, a com- 
paratively mild affection ; pneumonia typhodes, a grave disor- 
der; diphtheria, a malady of similar gravity; cholera, a dis- 
temper universally dreaded; and erysipelas, likewise serious 
in its character. These maladies, when appearing in an epi- 
demic manner, are in some instances apparently caused, and 
in other instances perhaps merely diffused, by atmospherical 
conditions, the precise nature of which we are for the most 
part ignorant. In three of them, symptoms of irritation and 
inflammation of the respiratory tracts are particularly notice- 
able ; in one of them lesions of theprima via are as peculiarly 
marked, while in another the dermic tissue is specially in- 
volved. 
These disorders have been before grouped as ineteoratious 
affections. Diphtheria and cholera are now recognized as 
contagious diseases ; but their prevalence is at times so pecu- 
liar and general that it has been difficult to ascribe their spread 
to contagion alone. It seems proper, in our present state of 
knowledge, to admit that the germs of these maladies, as de- 
rived from patients, meet with aerial and terrene conditions 
particularly favorable to their diffusion, and consequently 
many more people are smitten by them than those coming 
in contact with the sick. 
The poisons of the other affections have seldom, in this 
country, offered opportunities for study. Their sudden and 
wide-spread appearances seem to teach that atmospherical 
conditions are important factors in their production. 
Epidemic influenza and typhoid pneumonia have only 
occasionally been observed here. Diphtheria, while it has 
prevailed in our territory as early as 1751, and at a few sub- 
sequent periods, had attracted little attention until within a 
few years. Of late, especially in our large cities, its poison 
has become acclimated, and like the variolous virus is con- 
stantly operative, but not always in an epidemic manner. The 
disorder possesses a contagious element. While little can be 22 
done to correct any general condition of the atmosphere which 
favors the diffusion of diphtheria, yet the local measures of 
purification now in vogue are potent in preventing the exten- 
sion of the disorder by contagion, and by thus destroying the 
local foci of disease we prevent also its diffusion by meteora- 
tious influences. 
Repeated opportunities for studying epidemic cholera both 
on shipboard and on land have been afforded during the cen- 
tury ; but science has failed to deline specific choleraic germs. 
The study of the subject, however, has not been nugatory. 
The conditions favoring the development and spread of this 
disorder are allied in character to those favoring the outbreak 
and diffusion of several other forms of pestilence. The germs 
of the disorder are supposed to be microscopic vegetative 
growths ; such, indeed, is the present prevalent opinion. The 
perennial habitat of its peculiar poison is India; and the world, 
to a greater or less extent, is perennially inoculated with cholera 
from this great focus of the disease. 
Routes of travel are its favored highways. The traveler 
may convey by luggage, etc., from an infected region the 
germs of a poison which, under favoring circumstances, may 
smite him with death in a distant land. A case thus devel- 
oped is capable of spreading the disease to those about him 
through the material vomited, ejected from the bowels, or 
eliminated by the kidneys, unless such oral, anal, and renal 
excreta are disinfected either by a strong acid or by similar 
potent means of destruction. When such measures are not 
resorted to, and large numbers of cases are suffering from the 
disease, the general atmosphere may become so contaminated 
as to carry the poison for some distance; but the distance to 
which it can be meteoratiously spread is uncertain. I cannot 
enlarge on this topic, but would remark that, if our sanitary 
guardians keep informed in reference to the foreign prevalence 
of the malady, steps can be taken here to prevent either its in- 
troduction or its general prevalence. A recent report, pub- 
lished under the auspices of the United States Congress, very 
truthfully says: “Nothing is more clearly proved by the his- 23 
tory of cholera than that epidemics of this dreaded disease 
can he controlled by vigorous hygienic measures. The true 
remedy aga inst cholera is preventive medicine.” 1 
Regarding epidemic erysipelas, it may be said that few 
opportunities have been offered for studying its peculiarities. 
The disorder is kindred in its nature to the one originating in 
our hospitals, but differs from it in appearing over large sec- 
tions of territory. 
Another disorder to which no allusion has been made oc- 
casionally prevails in an epidemic manner, and is peculiarly 
distressing on account of the class of persons affected thereby. 
Reference is made to puerperal fever. While it may not be 
possible to prevent sporadic cases of the malady, nevertheless, 
its ordinary prevalence in lying-in asylums is attributable to 
gross and culpable carelessness, and, with our present knowledge 
of the etiology of the disease, its conveyance by accoucheurs, 
attendants, etc., is an iniquity scarcely less abhorrent than that 
of inducing criminal abortion. The efficient means now em- 
ployed to prevent the outbreak and spread of the distemper 
in maternity hospitals, and to prevent the portability of its 
poison from these institutions and from cases in private prac- 
tice, and of congeneric poisons to women about to be confined, 
if properly carried out, can almost eradicate the affection. 
Such prophylaxis is a result of the intelligent study of the 
subject within a comparatively few years. 
Ro more interesting field of study regarding epidemics is 
to be found than that relating to armies when engaged in 
active service. During the world’s history, the javelin and 
lance, the sling and falchion, the tomahawk and bayonet, shot 
and shell, have killed their hundreds of thousands ; but, while 
contending arms have sacrificed innumerable hecatombs of 
lives, during these same strifes disease has proved a more dis- 
astrous foe of valiant battalions than inimical weapons of war. 
The countless belligerent forces which have from time to time 
been mustered, containing the youth, the pride, the flower 
1 “ Cholera Epidemic of 1873 in the United States,” Washington, 
1875, p. 19. 24 
ol the earth, and whether or not engaged in holy or unholy 
warfare, have time and time again been desolated by disease. 
Indeed, an almost decimating decimation has occasionally 
withered the power of what has seemed an invincible force. 
Ancient history has embalmed the memories of surgeons 
of former days. We linger when reading of the care bestowed 
upon the wounded Machaeon, we mourn when learning of his 
decease, we rejoice at the divine honors paid to his memory, 
and hallow the temple erected in his honor at Massenia. But 
the medical officers of those days were chiefly lauded for their 
surgical abilities—their modern brethren must possess skill of 
a wider latitude. 
The causes which have induced disease and death among 
soldiers in their active campaigns until a comparatively re- 
cent period, if not overlooked, have not, at least, received that 
prophylactic attention which humanity demanded. As lately 
as during the Crimean war—a war in which civilized nations 
were contending, in which the prowess, the strategy, the en- 
gineering skill, and the mighty armaments of strife of the 
nineteenth century, were on trial and being scanned by the 
world—a waste of human life was permitted from preventable 
diseases which has cast a stigma on nations, the bravery of 
whose soldiers has elicited the plaudits of continents. 
Our own republic was plunged soon after in the horrors 
of civil war—a war which called into the service, including 
reenlistments of veteran volunteers, an army of loyal citizens 
numbering 2,753,723. The lessons learned from the Crimean 
war had been studied on this side of the Atlantic. “We 
were left to no vague conjecture as to the causes which pro- 
duced the fearful mortality among allied troops before Sevas- 
topol—a mortality which, as lias been truly said, has never 
been equaled since the hosts of Sennacherib fell in a single 
night.” 
The proclamation of the President of the United States, 
calling for troops, was issued on the 15th of April, 1861, and 
with its echo was heard the tap of the drum, simultaneously 
firing the patriotism and philanthropy of the North. The 25 
recruit was scarcely under marching-orders when means were 
being devised to protect him from disease. 
On the 23d of April, 1861, but eight days after the Presi- 
dent’s manifesto, an association of physicians was formed in 
this city known as the “New York Medical Association for 
the Supply of Lint, Bandages, etc., to the U. S. Army.” The 
object of the society was not alone to furnish means for the 
treatment of wounded, but to provide as far as possible, to 
the regiments gathering at the front, hospital clothing, etc., 
for rapid equipments included bare necessities; and recruits 
would almost necessarily suffer from disease in their sudden 
transition from civil to military life. 
The society had an existence of three months, and num- 
bered fifty-five physicians, many of them Fellows of this Acad- 
emy. During this time eighteen hundred dollars in money was 
collected and judiciously expended ; vaccine virus was distrib- 
uted to various regiments and the hospital at Fortress Mon- 
roe; numerous articles gathered from the benevolent of an es- 
timated value of $11,548.1:6 were carefully dispersed to thirty- 
six regiments, six hospitals, to the Naval Department, to the 
Medical Purveyor U. S. Army, and articles of diet placed in 
a proper channel to reach those requiring them. 
While this and numerous other initial local steps were be- 
ing taken to aid in maintaining the physical integrity of the 
army, wise measures were being devised to concentrate into a 
single organization the benevolence of loyal States. As the 
result of such deliberation the TJ. S. Sanitary Commission 
was organized on the 12th of June, 1861. While the Govern- 
ment was sufficiently animated in its efforts to preserve the 
national Union, it scarcely appreciated the importance of san- 
itary regulations to maintain the health of troops, and it 
needed the stimulus of an association fresh from the people to 
arouse it to a full sense of duty in this regard. The project 
of infusing civil aid in military administration met with dis- 
approbation in certain official quarters. 
It would be impossible on an occasion like the present to 
describe the work performed by this association—an associa- 26 
tion fostered at its incipiency by several of the distinguished 
Fellows of this Academy, and aided in various ways by a num- 
ber of us, both here and “ at the front,” by voluntary services. 
Can a few sentences or paragraphs epitomize its operations? 
Under the auspices of the Sanitary Commission, military, 
medical, and surgical monographs were prepared relating to 
the prevention of disease, and to the hygienic as well as med- 
ical management of the disorders and injuries incident to war. 
Salutary advice was afforded regarding the proper sites tor 
camps and for the sites and proper modes of construction of 
hospitals. A corps of special inspectors of the general hos- 
pitals of the army was appointed, composed of gentlemen of 
known repute. No less attention was called to the dietary of 
troops, and through the agency of the association scurvy was 
prevented in some sections of the country, and its ravages ar- 
rested in others. Special care was taken for the moving of 
sick and wounded by means of thoroughly-equipped ambu- 
lances, hospital cars, and transports. 
Armies stationed in unhealthy localities were made objects 
of special surveillance. At New Orleans the commanding 
general and Ur. McCormick, medical director of the depart- 
ment, were alert in guarding the soldiers from disease. “ The 
fear of the outbreak of yellow fever during the summer months, 
and the danger to which a Northern army would be exposed 
by its prevalence, acted as a constant stimulus to the most 
careful measures of prevention 1 . . . . Early in July, 1862, 
the whole number of sick in that department, in regimental 
and general hospitals, was only four hundred and seventy-two 
out of a iorce of about twenty thousand men (nineteen regi- 
ments of infantry and seven batteries), less than two and a 
half per cent. . . . This favorable state of health among the 
troops in the Department of the Gulf was maintained during 
the whole war. In November, 1863, the experienced inspec- 
tor of the commission, Dr. Crane, writes : ‘ I have never seen 
so little disease among troops in the field. But little over 
four per cent, of the present force is on the sick-list.’ ... It 
1 “ United States Sanitary Commission Memoirs,” Philadelphia, 1866. 27 
is certainly very remarkable that a far higher health-rate was 
maintained during the war among the troops on the coast of 
Carolina and the delta of the Mississippi than in the moun- 
tainous regions of Tennessee and Virginia.” 
Never before in the world’s history had such powerful 
forces been gathered and been protected by sanitary care—the 
voluntary gifts to provide for such protection amounting to 
nearly five million dollars. It was the enlightened care on 
the part of the people and of the Government of their troops 
which contributed in no small degree to the maintainance of 
the integrity of a nation whose centennial birth-year we now 
celebrate. The lessons derived from the war are not to be 
forgotten, but will prove of value to coming generations. In 
future conflicts of the earth Hygeia will assert her supremacy 
beside that of Mars, and the horrors of war be gradually and 
gradually diminished, until the time shall come when 
“ No more shall nation against nation rise, 
Nor ardent warriors meet with hateful eyes, 
Nor fields with gleaming steel he covered o’er, 
The brazen trumpets kindle rage no more; 
But useless lances into scythes shall bend, 
And the broad falchion in a ploughshare end.” 
The sanitary experiences of the late war have taught les- 
sons which had never been so thoroughly impressed, and which 
are as important respecting civil as military life. They have 
shown that insalutary places can he made comparatively salu- 
tary, and have almost shown, to use the words of another, 
that “vanquished Nature yields its empire to man, who cre- 
ates a climate for himself; ” they have illustrated the fact that 
men may he congregated in vast numbers, and yet not be 
mercilessly ravaged by disease; they have proved that a 
proper dietetic regimen will arrest the progress of and prevent 
certain disorders; they have demonstrated that pure fresh air, 
which is so lavishly and beneticiently distributed by Nature, 
is a more powerful factor in the relief of sick and wounded 
than medicinal herbs and minerals, which are also benefi- 28 
ciently provided, but arc offered more sparsely, and as mere 
adjuvants to the breath of life. 
The results of these and of other teachings derived from 
the same experience are already apparent, and have influenced 
public opinion. As an illustration of* this, I need only refer 
to the prevailing views regarding hospital construction. While 
the disadvantages of ordinary infirmary buildings had long 
since been observed, never had communities been brought to 
fully realize their imperfections until, on a large scale, the 
advantages were shown of treating patients either in tents or 
in inexpensive, simple, commodious, and thoroughly-ventilated 
pavilions. Such structures are as well adapted to the treat- 
ment of civilians as of soldiers; and, while for civil purposes 
they should be built in a more durable manner than those 
employed during periods of war, nevertheless, they should not 
be very permanent in their nature, but be destroyed after a 
comparatively few years of an intermittent occupancy. Mr. 
James W. Beekman, in writing on this subject, has well said: 
“The architectural necessities are light, air, speedy removal 
of refuse, and great facility in cleansing. Architectural dis- 
play in a hospital is a crime. £ Do not build for a long fu- 
turity.’ ” 
While such axioms are becoming household words, they 
are dispersing knowledge of a wider significance than their 
literal interpretation would convey. If the homes of the sick 
must be models in their sanitary arrangements, an antithesis 
of like importance is believed to be true, and as a result in- 
creased attention is being paid to the proper construction of 
all kinds of human habitations, and more attention is being 
paid to the selection of their sites, etc. 
In this brief arid desultory review which I have given of 
my subject, it may be said that little has been advanced of a 
positive nature in regard to the specific poisons which occa- 
sion the epidemics and zymotic disorders which have been 
considered. I have refrained from giving in detail the vari- 
ous prevailing theories regarding them, and one reason for 
such omission may be found in the fact that the most accom- 29 
plished experts shrink as yet from defining: with certainty the 
precise nature of these subtile deleterious agents. 
The medical world is now engaged, as I have before said, 
in a special study of minute vegetable organisms, to say noth- 
ing at present of the lower forms of animal existence and of 
the influence exerted by them in various diseases. They are 
found in certain processes of inflammation, in tissues, in secre- 
tions and excretions, and in the atmosphere. We are seeking 
intently for the biography of parasites, for information re- 
garding their germs, their growth, their longevity, and their 
death. We are endeavoring to learn at what periods of their 
existence they may be offensive, and whether or not it is the 
germ or the parasite which is capable of being conveyed or 
of remaining in a passive condition awaiting favorable circum- 
stances for increased growths. Ordinary vegetation affords 
edible and poisonous growths ; microscopic vegetation is not 
destitute of potent properties. 
Kindred to this subject of vegetable parasites is that branch 
of science which has been developed during the century, viz., 
helminthology or entozoology. Between thirty and forty hu- 
man entozoa have been carefully described. Many of these 
in their adult life are of such magnitude as to have early at- 
tracted notice. Moses doubtless alluded to dracunculi or 
Guinea-worms when describing the “ fiery serpents which 
afflicted the children of Israel during their stay in the neigh- 
borhood of the Bed Sea ” (Cobbold), and Agatliarchides doubt- 
less alluded to the same helminth in his clever account of the 
“little snakes” affecting the limbs and muscles of the inhabi- 
tants of the same seaboard. 
While several animal parasites were of sufficient size to 
have early attracted notice, nothing was definitely known, un- 
til comparatively recently, concerning their origin, their larvae, 
their growth, their migrations, and again several entozoa were 
so diminutive in size as to have altogether escaped observa- 
tion until discovered by microscopic assistance. 
A number of diseases prevail among inferior animals at- 
tributable to entozoa, and among mankind from similar causes. 30 
Several of the former appear as epizooties and of the latter 
as epidemics. Of the epizooties, the more noticeable are the 
gapes, a disorder prevalent among poultry and among a num- 
ber of birds depending upon the presence of scerostomata in 
the trachea, a disease first described by Dr. A. Wiesenthal, of 
Baltimore, in 1799; the rot-disease, especially destructive 
to sheep, and caused by the presence of the fasciola liepatica, 
or liver-fluke; the disorder among swine attributable to trich- 
inae ; the malady among swine, dogs, wolves, etc., due to tae- 
niae. Of the epidemics due to entozoa, the most interesting 
for present consideration are those due to taeniae and trichinae. 
How greatly has our knowledge been increased within a 
few years concerning the cestoidea or tapeworm group of hel- 
minths, due in great measure to the experimental study of the 
subject by Yon Siebold and Kiiclienmeister! How carefully 
have cystic worms and larvae been observed, their migrations 
noted, and the diseases induced by them in their various stages 
of development been described ! 
What interest has been awakened in regard to nematoidea or 
round worms, especially as relates to the trichina spiralis. The 
history of the life and peculiarities of this parasite has been 
as carefully depicted as if it was one of our familiar domes- 
ticated animals. Zoologists have carefully described to us the 
fauna of continental areas and of epochs, and are now furnish- 
ing us with volumes relating to entozoa. 
As a result of such labors, agricultural interests have 
been promoted by preventing diseases among important in- 
ferior animals, and mankind has been further benefited by 
escaping a number of loathsome diseases. Fortunately our 
country has not been very seriously invaded by this class of 
maladies. Further labors in the direction indicated must be 
prosecuted; unrecognized entozoa are doubtless inducing mis- 
chief, arid the habitats of those which are known are not fully 
appreciated. 
In the civilization of our century, Europe, Asia, Africa, 
and America, are freely interchanging commercial commodi- 
ties. While gems and bullion, cereals and fruit, fabrics and 31 
manufactures, are being widely distributed for the comfort of 
mankind, let science prevent the diffusion of entozoic fauna 
by preventing human contamination with them in the respec- 
tive continental habitats of these obnoxious helminths. 
Zoological investigations relating to parasites are in ad- 
vance of botanical researches concerning minute vegetable or- 
ganisms, but while this is so, we are gathering important in- 
formation regarding vegetative germs as effecting cholera, 
diphtheria, typhoid fever, and other disorders. Such studies 
are being prosecuted with the same zealous spirit as that wThich 
actuated Linnaeus, Wolff, and Goethe, in other departments 
of botany, and are to be crowned with a similar success. As 
yet we stand at the threshold of the branch of science under 
special consideration, and are merely pioneers. In this re- 
spect, we may almost be said to be contemporaneous with Zo- 
roaster, Aristotle, and Plato, in their study of the general sub- 
ject of botany. 
This being the case, the question arises : Have the benefits 
of sanitary science been overestimated? The ultimate nature 
of light has not been absolutely defined, but its salutary effects 
are clearly intelligible. The precise nature of electricity is 
not fully understood, but its nature and properties are suffi- 
ciently appreciated to be utilized in an almost miraculous 
manner. So various occult morbid influences are known to 
be operative by the prevalence of peculiar phenomena. The 
causes favoring such prevalence are often discernible, and if 
not directly discernible the causes favoring their prolonged 
operations can be clearly observed and appropriate prophylac- 
tic measures can be resorted to. While neither municipal, 
State, nor Federal legislation can enact and enforce laws so 
governing the private life of a citizen as to promote his 
healthy growth, nevertheless jurisdiction can impose laws 
which restrain an individual from jeopardizing the lives of his 
neighbors by his sanitary negligence, and can regulate matters 
relating to public hygiene. 
The enlightened nations of the earth are now paying spe- 
cial attention to hygienic legislation and to the promulgation of 32 
sanitary instruction. Sovereignties and municipalities alike 
are vigilant in guarding the general physical welfare of the 
people. Intelligent boards of health are now established 
throughout our land in the larger cities, and the villages are 
instituting similar provisions of safety. This salutary state of 
affairs, which has comparatively recently been inaugurated on 
so comprehensive a scale, has been due to the persistent as- 
siduity of our profession in pressing upon communities the 
important results to be derived from such organizations. 
While the boards of health alluded to may at times fall into 
unskilled management, such transfer can be but temporary, as 
the people are already convinced that scientific skill must 
wield the helm in such departments, and will never consent 
to revert to that condition of sanitary apathy which but a 
few years ago was so apparent to medical men. 
But we must not be content in urging alone the establish- 
ment of local boards of health. State boards and national 
boards must be organized, having a recognized official au- 
thority. Between the local boards and those of the state and 
nation there must be authoritative communication, and the 
national boards of the various countries of the earth must 
unite in holding official correspondence relating to matters of 
the public health. Some such provision of safety will assur- 
edly become established. 
Already we recognize the advantages to the nation from 
the daily reports of the War Department relating to the 
weather. The numerous meteorological observations made at 
distant points, and diurnally, at fixed hours, telegraphed to 
Washington, are concentrated under scientific supervision into 
terse dispatches, and daily published throughout the land, 
giving the areas of storm and dryness, of heat and cold, and 
foretelling the approach of tempest, of calm, and sunshine— 
thus aiding commercial, agricultural, and other interests. A 
somewhat similarly arranged sanitary department must take 
its place among the national bureaus. 
A few more thoughts must be offered on a subject to which 
slight allusion has only been made. When epidemic causes 33 
of disease are prevalent, to say nothing of the personal means 
suited to induce vigor, to say nothing of ventilation, of drain- 
age, sewerage, etc., of domiciles and localities, as aids in 
escaping injury, chemistry affords efficient agents to neutral- 
ize pernicious local conditions which are contaminating the 
atmosphere. These agents have chiefly been presented by 
modern science, and are the outgrowth of the century. 
Human ingenuity, however, has long been exercised in this 
direction. While we may now deride many ancient customs, 
some of which were of superstitious origin, and many arts of 
the alchemists, we must bear in mind with respect many primi- 
tive means of disinfection and preservation. Jewish priests 
exercised hygienic supervision of households and used appro- 
priate means in purifying the clothing and dwellings of those 
afflicted with the leprosy. Herodotus and others have re- 
corded the manner of embalming the dead. Egyptians early 
understood the processes of drying to prevent decomposition. 
Ulysses burnt sulphur to destroy the infection arising from 
dead bodies, and Roman shepherds burnt sulphur and herbs 
when sacrificing to Pales, the goddess of their sheepfolds. 
It is unnecessary to multiply examples of this nature which 
illustrate dim insights into a science into which we are peer- 
ing, and even still quite cloudily. Nevertheless, progress has 
been made, and we possess a group of disinfectants which may 
be classified as follows : 1. Those which destroy or prevent the 
multiplication of the lower forms of organized bodies; 2. 
Those which have the property of absorbing deleterious prin- 
ciples and thus rendering them inert; 3. Those having the 
power to decompose various noxious agents into less poisonous 
or innocent principles. This classification as a matter of con- 
venience is sufficiently accurate for our present purpose and 
partially exhibits the precision aimed at by modern science. 
Besides these we recognize the potent agencies of heat and cold. 
“ In such indexes, 
There are seen 
The baby figures of the giant mass 
Of things to come at large.”—Shakespeare. 34 
The chemical agents which we can now utilize as disin- 
fectants are more numerous and, in many respects, are vastly 
more potent than any hitherto otfered, and animate us to fur- 
ther exploration and further achievements as the land-growths 
wafted to the ship of Columbus stimulated to a prolonged and 
successful search for our Western Continent. 
Entering on a new century under most favorable auspices, 
it can safely be predicted that before its ten decades have been 
spent, measures of prophylaxis and of therapeutics will be 
established of far more importance than any of those which 
during the previous history of the world have been developed 
by scientific ingenuity.