THE VENTILATION OF SCHOOL-ROOMS 
HEATED BY STOVES. 
By J. G. PINKHAM, A. M., M. D., LYNN. THE VENTILATION OF SCHOOL-ROOMS 
HEATED BY STOVES. 
J. G. PtNKJIAM, A. Nf., M.D., LYNN THE VENTILATION OF SCHOOL-ROOMS HEATED 
BY STOVES. 
By information derived from replies to a circular letter of 
inquiry issued by the State Board of Health, and addressed 
to the school authorities of all the cities and towns of the 
State, it has been ascertained that there are in the State 
about 3,860 school-rooms heated by stoves, and that these 
rooms accommodate 131,200 pupils. 
The subject proposed for discussion in this paper may be 
seen by the above figures to be one that concerns directly the 
welfare of more than one-third of the school population of 
the State. It is a subject which has received less atten- 
tion from writers upon school hygiene than its importance, 
as thus shown, would seem to demand. 
A majority of the school-rooms under consideration are 
in country districts, or in villages, and in buildings that 
contain but one or two rooms. That they should be heated 
by some form of stove seems almost a matter of necessity. 
Open fire-places and grates do not furnish heat enough for 
very cold weather. With so humble a class of buildings, 
heating by steam or by hot water is out of the question. 
In many cases there is no cellar or basement; hence the 
hot-air furnace could not be employed without a large pre- 
liminary outlay. Moreover, as ordinarily used, the furnace 
is an expensive and unsatisfactory method of heating. 
Taking it for granted, therefore, that stoves will continue 
to be used in these rooms, the question of ventilation must 
be considered in connection with this form of heating. 
In the following pages it is proposed, first, to describe 
briefly the prevailing methods of ventilation in such rooms, 
and point out, in a general way, their defects; secondly, to 316 
STATE BOARD OF HEALTH. 
[Jan. 
show that by means of jacketed stoves it is possible to 
heat school-rooms satisfactorily, and at the same time to 
supply a sufficient amount of pure air without disagreeable 
or dangerous draughts. 
I. Prevailing Methods of Ventilation. 
The reports of our correspondents throughout the State 
indicate that, with very few exceptions, the school-rooms 
that are heated by stoves are supplied with means for 
only the most simple form of natural ventilation. That is, 
a communication is made with the outside air, and such 
an exchange of that with the air of the room is allowed 
to take place as is brought about naturally by the difference 
in temperature or the force of the winds. 
In nine-tenths of the rooms reliance is placed mainly 
upon doors and windows as means of ventilation. About 
one-fourth of them have some special appliances attached 
to the windows, either at the top or bottom,-the object 
being to give an upward direction to the inflowing current 
of air, or to so divide and diminish it that the draught 
may be less sensibly felt. Among the devices used in con- 
nection with window ventilation are the following : - 
1. A narrow strip of board placed under the lower sash, 
the air being allowed to enter at the middle of the window 
between the sashes. 
2. A strip of board nailed to the casing across the lower 
part of the window. When the lower sash is slightly raised 
air enters between it and the board, and also between the 
sashes. 
3. A screen of fine wire netting fastened to the window- 
casing on the outside. 
4. A box, open on the upper and outer sides, fastened 
to the window-casing at the top, in such a way that when 
the upper sash is lowered a current of air enters and is de- 
flected upward toward the ceiling. A strip of board fast- 
ened obliquely in the same situation, or hinged and opening 
inwards, is sometimes made to effect the same result as the 
box. 
5. Revolving ventilators, occupying the space of the 
window-pane. 1888.] 
VENTILATION OF SCHOOL-ROOMS. 
317 
6. Double windows with holes through the bottom bar of 
the frame of the outside window. When the top sash of the 
inside window is lowered fresh air is admitted. 
7. Ducts passing through a board placed under the lower 
sash, and turning upward. 
A few of the rooms are furnished with other means of 
ventilation, such as the following : - 
1. Transoms over doors and windows. 
2. Openings in the side walls of the buildings, mostly 
near the top of the room. 
3. Openings in floors. 
4. Openings in ceilings. These either communicate with 
the outer air by means of a duct which extends up through 
the roof, or they open directly into the attic. In the latter 
case the attic becomes a foul-air chamber from which access 
to the outer air is had through the window, by an opening 
in the roof, or not at all. 
5. Special flues in chimneys, or openings into smoke 
flues. 
All these methods of ventilating, or more strictly speak- 
ing varieties of one method, are open to the objections that 
they cannot, under ordinary circumstances, supply air enough, 
and that they make no provision for warming the incoming 
air in cold weather. That they cannot supply air enough is 
true at all times of the year except when the weather is so 
warm as to allow the free opening of doors and windows. 
A reasonable estimate of the amount of fresh air required 
by the pupils of an ungraded school would be two thousand 
cubic feet each per hour. For a school-room containing ten 
thousand cubic feet of air-space, and accommodating forty- 
five pupils, this would mean that eighty thousand cubic feet 
of fresh air must be supplied each hour, or that the air of 
the room must be changed completely once in every seven 
and one-half minutes. The impossibility of effecting such 
a result in cold weather, and of keeping the room warm at 
the same time, with the means of heating and ventilating in 
common use, must be apparent to any one ; and without 
regard to the temperature of the room, it would be dillicult- 
to effect it except by means of widely opened windows or 
doors, and a strong breeze blowing directly in. [Jan. 
318 
STATE BOARD OF HEALTH. 
The openings between window sashes, so much depended 
on for ventilation, are very small; probably they do not 
average for the different windows more than twenty square 
inches.* Six of them would amount to only one hundred 
and twenty square inches, or five-sixths of a square foot. 
If, in the case supposed above, we should allow six windows 
with strips of board under the lower sashes to act as inlets, 
provision being made for the escape of foul air by an open- 
ing in or near the top of the room, we should have as 
favorable conditions for good ventilation as one would be 
likely to meet with in school-rooms heated by stoves. If 
air should enter at the rate of two hundred linear feet per 
minute, - a liberal estimate,-the amount supplied would 
be ten thousand cubic feet per hour, just one-eighth of 
what would be needed. If no escape for foul air were pro- 
vided, as is often the case, some of the windows would have 
to act as inlets and others as outlets,-in which case the 
movement would be slower, and the air supply much less. 
The above is a fair picture of ordinary school-room venti- 
lation at its best. Add to the amount given the air which 
finds entrance through the cracks of a poorly constructed 
building, and that which is admitted by opening doors and 
windows during recess, or periods of exercise, and we still 
do not have enough to prevent the air of the room from 
becoming decidedly foul, and remaining so during a consid- 
erable portion of the time when the school is in session. 
The truth of this statement will be clearly shown later by 
means of observations made upon some of the school build- 
ings in the city of Lynn. 
But even this limited air supply involves a certain amount 
of danger in cold weather from draughts and unequal heat- 
ing. The evil is not imaginary. It is extremely common 
for children who are compelled to sit near open windows in 
school-rooms to complain of the draught, and to take cold 
from this cause. It is quite as common for those who sit 
near the stove to suffer from an excess of heat. On very 
cold days-not a few in this latitude-it is necessary to 
* The most narrow part of these openings should be measured. This is usually 
the space between the lower bar of the upper sash and the lower window-pane. For 
many rooms the estimate given is doubtless too high. 1888.] 
VENTILATION OF SCHOOL-ROOMS. 
319 
cut off entirely, or as far as possible, the fresh air supply, in 
order to keep the room comfortably warm. At such times 
the foulness of the air becomes painfully noticeable to those 
who visit the school. Nearly all of those who made reply 
to the circular letter before referred to admit that, as a rule, 
the school-rooms in which stoves are used are unequally 
heated and badly ventilated. 
A few extracts from the replies of our correspondents are 
given, to show the opinions entertained on this subject by 
those who have charge of the schools : - 
1. All our schoolhouses are heated by stoves. Very little at- 
tention is given to ventilation. The houses are old-fashioned, 
country schoolhouses, one story high, consisting of one room, 
nearly square, with a hall and wood-room at one end. The rooms 
are liable to become uncomfortably warm or cold in a short time. 
2. In all the rooms in which dependence is placed upon win* 
dow ventilation, the forgetfulness or neglect of teachers engenders 
great and frequent risks to health by cold currents or draughts 
upon children. 
3. Windows opened at top. Results unsatisfactory. If hot 
air goes out, cold air comes in. It strikes the heads near by, and 
induces catarrhal troubles. m. d. 
4. While we instruct the teachers to keep one or more windows 
down at the top all the time, and to ventilate thoroughly at recess, 
still, from neglect or fear of exposure, we often find the air foul 
and unfit for breathing. I should be glad to find some means for 
more perfect ventilation. 
5. The ventilation of all our rooms which are heated by stoves 
s very unsatisfactory. We are forced to depend on the windows 
ifor a supply of fresh air, and can only keep the atmosphere of the 
rooms wholesome by frequently throwing these wide open (during 
recess or the time devoted to gymnastics) and creating a strong 
cross current. 
6. The ventilation of our school-rooms is very unsatisfactory 
and imperfect. 
7. Very little attention, if any, given to the principles of ven- 
tilation. 320 
STATE BOARD OF HEALTH. 
[Jan. 
8. In none of our schools is there any method of ventilation, 
except that of opening doors or windows. Lack of ventilation 
and untidy wTater-closets, or privies really, are among the most 
prominent defects in our schoolhouses in this town. I am glad 
that the matter is being investigated by the State. 
9. Our high-school room was built with ventilation in the floor 
and in the chimney, but the committee finding the floor ventila- 
tion a nuisance discontinued it. It being an upper room, the 
ventilator admitted both cold and foul air. The chimney ventila- 
tion amounted to but little. We now intend to place a strip of 
board at the bottom of the window, and, raising the lower sash 
upon it, allow the ah* to enter where the two sashes come together. 
II. The Use of Jacketed Stoves. 
It may be taken for granted that it is impossible to sup- 
ply school-rooms with the large amount of fresh air required 
for proper ventilation, and at the same time keep up the 
temperature, unless provision is made for warming the air 
before or during its introduction. To accomplish this 
economically with the class of rooms under consideration, 
the jacketed stove, or some form of heater arranged on 
the same principle, seems to be the only available device. 
The plan is not new. It has been in use for many years 
in one form or another; but the writer is not aware that 
any account has been published hitherto of a systematic 
attempt to secure by this method air enough to meet the 
requirements of a perfect system of ventilation. In the 
replies of our correspondents mention is made of the use of 
jacketed stoves in forty-two rooms in different cities and 
towns throughout the State. Six of those rooms are in 
Lynn. A detailed account of the plan pursued in them and 
of the results attained is to be given in this paper. In regard 
to the other rooms the information furnished is so meagre 
that it is impossible to judge whether the system has been 
successful in them or not. 
Experience in Lynn. - The work about to be described 
was performed under the direction of the committee on 
sanitation of the Lynn school board. 1888.] 
VENTILATION OF SCHOOL-ROOMS. 
321 
The air analyses were made by Prof. Wm. B. Hills, of 
the Harvard Medical School. 
The diagrams and charts were prepared by Mr. T. P. Per- 
kins, civil engineer, of Lynn. The latter gentleman also 
collected the air samples and made the observations re- 
corded in the tables accompanying the charts. 
Three primary-school buildings, each containing two 
rooms, have been heated and ventilated in thegway men- 
tioned. The arrangement at the lied Rock Street school- 
house has given the best results, and is regarded as the most 
worthy of imitation. For this reason it will receive a some- 
what more particular description than that at the other 
buildings. 
Red Rock Street Schoolhouse. 
This is a brick building of good construction and in a 
healthy locality. The ventilating apparatus was put into it 
during the summer of 1886, and the description which fol- 
lows is from the report of the committee on sanitation for 
that year: - 
There are in each room two large stoves ( Barstow's " Puritan," 
No. 18), one on each side of the room, near the front. Each 
stove is encased in a galvanized iron jacket about six and one-half 
feet high, with a spreading base. Air is admitted to the space 
between the stove and its jacket by an air-box running through 
the side wall, the opening for each stove having a sectional area 
of four and one-half square feet, being large enough for the whole 
air supply of the room. In cool weather one stove in each room 
is used ; in cold weather both stoves. 
There are two extraction flues, built in one stack, at the rear of 
the building, one with a sectional area of 5.2 square feet for the 
upper room, and one with a sectional area of 4.1 square feet for 
the lower room. They are of brick, and in an inner corner of each 
is a fire-clay smoke pipe connecting with the stove pipes. These 
smoke pipes end at the level of the chimney top, and the whole is 
covered with an iron cap, like an Emerson ventilator, but rectan- 
gular. For heating the flues one of D. W. Cushing's 'k Ring 
Cylinder" stoves is set into the with, or partition between the 
flues, projecting into each. The flues are enlarged opposite the 
stove to compensate for the obstruction of its bulk. As the cellar 
does not extend under the rear of the building the flues end at the 322 
STATE BOARD OF HEALTH. 
[Jan. 
floor level of the lower room. The openings from the rooms into 
the extraction flues are macle at this level, from the lower room 
directly through the wall, and from the upper room by means of a 
thirty-inch tin pipe, running down beside the stack, from the upper 
floor. The flue-heating stove is set about three feet above the 
lower floor, and access to it is had through an iron door opening 
into the school-room. Most of the air withdrawn from the rooms 
goes through large openings close to the stack ; the remainder 
( 15 or cent.) is drawn through ducts under the back plat- 
form, and thence into the extraction flues. The total area of 
outlet openings from each room is about equal to the sectional area 
of its extraction flue. All outlet openings are covered with wire 
netting of about one inch mesh. Inlets on outside of building 
are protected by boxing and fine netting. 
The illustrations which follow will make this description 
plain. All dimensions are given in the floor-plan and sec- 
tions. The capacity of the lower room is 10,700 cubic feet, 
that of the upper, 12,040 cubic feet, allowance being made 
for chimney, platforms, stoves and jackets, but none for 
furniture or persons. The air space per scholar, using the 
average attendance during the winter term of 1886 as the 
basis of calculation, is for the lower room one hundred and 
ninety-four cubic feet, for the upper room two hundred and 
forty cubic feet. The actual air space enjoyed by each 
pupil in any school varies, of course, from time to time with 
the number in attendance. The average age of the pupils 
in the lower room is seven years, nine months ; in the upper 
room nine years, six months. The results at this schoolhouse 
have been most excellent, as shown by charts A and B, and 
the accompanying tables. There was no difficulty in manag- 
ing the apparatus after its working was fully understood. 
Visitors to the school note the seeming purity of the air, 
and the teachers bear similar testimony. 
Measurements of the outflowing air have been made at 
various times. These show an average for the lower room 
of 108,510 cubic feet per hour, or about 2,100 cubic feet 
to each pupil; for the upper room 84,664 cubic feet, or 
about 1,900 cubic feet to each pupil. In making these esti- 
mates the cubic contents of the rooms were added to the 1888.] 
VENTILATION OF SCHOOL-ROOMS. 
323 
outflow, and the average attendance of the pupils employed 
as a factor. 
It is probable that in mild weather these figures would be 
somewhat reduced. They might be considerably reduced, 
and still leave quite a liberal supply for pupils of the ages 
specified if the commonly received views as to the amount 
required arc correct. It is intended that the fire shall be 
kept burning in the flue-heating stove at all times, except 
in warm weather. In this way the air supply may be kept 
up when the jacketed stoves are not in use. 
The air analyses have very uniformly shown good results. 
Chase Avenue Schoolhouse. 
The arrangement at this schoolhouse differs from that at 
© 
the Red Rock Street schoolhouse in the following particu- 
lars only: - 
1. The chimney flues extend into the cellar and the foul 
air from both rooms is carried down by large tin ducts and 
discharged into them at the bottom. The flue-heating stove 
© © 
is in the cellar. The net area of each flue on cross section 
is 3.7 square feet. 
2. The extraction flues are of the same size through- 
out, and the smoke pipes pass up through the centre. 
3. The foul-air outlets, twelve in each room, are provided 
with registers, and arranged along the sides and back of the 
room. 
4. The chimney is capped with a louver, through which 
the smoke pipes extend. 
5. The fresh-air inlet in the lower room has an area on 
cross section of 4.4 square feet; that of the upper room an 
area of 2.47 square feet. The structure of the building 
made it difficult to put in a larger inlet duct in the upper 
room. 
These details are given because they furnish an explana- 
tion of the fact which will soon appear, viz. : that the amount 
of air supplied at this building is considerably less than at 
the Red Rock Street schoolhouse. 324 
STATE BOARD OF HEALTH. 
| Jan. 
RED ROGK STREET SCHOOL HOUST 
SECTION THROUGH HEATING STOVES AND FRESH AIR INLETS 1888.] 
VENTILATION OF SCHOOL-ROOMS 
325 
RED ROCK STREET SCHOOL HOUSE 
ECTION THROUGH CHIMNEY ON LINE PARALLEL TO REAR WALL 326 
STATE BOARD OF HEALTH. 
[Jan. 
RED ROCK STREET SCHOOL HOUSE LOWER ROOM 
PLAN VENTILATION OF SCHOOL-ROOMS. 
327 
1888.] 
RED ROCK STREET SCHOOL, LOWER ROOM, SHOWING ONE STOVE 328 
STATE BOARD OF HEALTH. 
[Jan. 
The air-meter tests have been difficult to make on account 
of the numerous outlets, and the somewhat indefinite amount 
of obstruction caused by the registers. The figures given 
are probably an under-estimate. Early in the year 1886 
measurements with the air-meter were made in the lower 
room, and showed an outflow of 45,000 cubic feet per hour. 
Two samples of air taken from this room at the same time 
were analyzed by Professor Hills with the following result: - 
No. 1. taken in front of the teacher's desk gave 7.93 vol- 
umes of carbonic acid in ten thousand volumes of air, and 
No. 2. taken in the back part of the room among the 
scholars, and at the breathing line, gave 9.68 volumes. 
The results of other examinations are shown in chart C 
and the tables. The amount of carbonic acid in the air of 
the lower room appears to be kept uniformly below ten. 
That of the upper room rises above ten just before recess 
and at the close of school. 
Before the improvements were made this building was 
notoriously the worst ventilated schoolhouse in the city. A 
sample of air taken from one of the rooms before recess 
showed nearly thirty parts of carbonic acid in ten thousand 
volumes of air. The close, bad odor of the rooms was 
observed by all who had occasion to visit them. 
The building was worse than others in this particular, be- 
cause it was better built, and hence more nearly air-tight. 
It had no available means of ventilation except the doors 
and windows. 
To enlarge the fresh-air inlet in the upper room, giving it 
an area on cross section of not less than four square feet; 
to remove the registers in both rooms, substituting coarse 
wire netting, or, still better, to close them altogether, and 
make large openings directly into the tin ducts which lead 
to the extraction flues, would probably place this building 
nearly on a level with the one on Bed Bock Street in regard 
to the amount of air supplied. 
As a matter of minor importance it may be mentioned 
that the louver on the top of the chimney is thought to be 
less effective for its purpose than the arrangement in use at 
the other buildings. 1888.] 
VENTILATION OF SCHOOL-ROOMS. 
329 
Baltimore Street Schoolhouse. 
This is an old wooden building, with thin walls, and of 
rather loose construction. The rooms are so arranged as to 
make it inconvenient to place the stoves in the front part. 
They were, therefore, placed in the back part, as shown in 
the illustrations. Those in the lower room are enclosed in a 
double jacket, and placed directly in front of the chimney. 
The fresh air is admitted to a chamber underneath the platform, 
and from thence is conducted to the jacket, traversing both 
stoves before its escape into the room. In the upper room 
the stoves are surrounded by cylindrical jackets and placed 
one on each side of the chimney. The smoke pipes open 
directly into the flues. The foul air from both rooms is 
carried down to the bottom of the chimney by tin ducts, as 
at the Chase Avenue schoolhouse. On account of the char- 
acter of the building it was not thought best to attempt to 
supply so much air as at the Red Rock Street schoolhouse. 
Hence the extraction flues and inlets were made somewhat 
smaller. The diagram shows a section through the chimney, 
the stoves in the upper room, the foul-air ducts, etc. The view 
is from the front, and the stoves in the lower room are shown 
in dotted lines. The arrangement in this building has an 
advantage over the others in that the apparatus occupies 
but little space, and is out of the way. It was put in during 
the summer of 1887, and has hardly been in operation long 
enough to determine fully its merits or defects. The obser- 
vations thus far made, as exhibited in charts D and E and 
the tables, prove that the air of the rooms is generally pure. 
But they show at the same time that there is occasionally a 
failure of the respired air to diffuse itself rapidly or to pass 
away from the breathing zone ; a fact which may, perhaps, 
bo accounted for by the entrance of cold air by other chan- 
nels than those which lead to the stove jackets. Such an 
event would not only keep the floor cold, but would cause 
the air in the middle of the room to remain more or less 
stagnant at times, - in fact, to give us the results shown by 
certain of the air analyses. That this is true, a brief con- 
sideration of the physical laws which control the move- 
ments of air under such circumstances will make apparent. 330 
STATE BOARD OF HEALTH. 
[Jan. 
BALTIMORE STREET SCHOOL HOUSE LOWER ROOM 
PLAN VENTILATION OF SCHOOL-ROOMS. 
331 
1888.] 
BALTIMORE STREET SCHOOL HOUSE 
SECTION THROUGH CHIMNEY ON LINE PARALLEL TO REAR WALL 332 
STATE BOARD OF HEALTH. 
[Jan. 
Samples of air taken at different altitudes from near the 
middle of the lower room, December 31, gave the following 
results : - 
Just before recess, at floor, 8.29 parts of carbonic acid to 
ten thousand volumes of air ; at the breathing line of pupils, 
13.66 parts; at the ceiling, 6.16 parts. Near the close of 
the session, at floor, 4.16 parts; at the breathing line, 6.51 
parts ; at the ceiling, 7.64 parts. The day was an extremely 
cold one, and as the fires had not received proper attention 
in the morning the room did not get fairly warmed until 
after ten o'clock. The upper ventilator in the chimney had 
also been left open during the early part of the session, 
allowing the pure, warm air to escape in the most direct 
way possible. When the room is well warmed, as it was on 
February 23, the date of the observations shown in the chart, 
the air is thoroughly diffused. This appears to be proved 
by the constant purity of the air at the breathing line, a fact 
which the analyses of that date show. Further comments 
upon the difficulties experienced at this schoolhouse will be 
made under the head of "Temperature." 
In order to show more clearly the contrast between these 
schoolhouses and those heated and ventilated after the old 
method, two of the latter will be described, and the results 
of observations made in connection with them given. As a 
matter of convenience they will be referred to as the unven- 
tilated schoolhouses. 
Jackson Street Schoolhouse. 
This is an old, two-story wooden building, something like 
the one on Baltimore Street, but with a slightly different 
arrangement of the rooms, as shown by the accompanying 
plan. For ventilation we have in the lower room a wooden 
duct, 12 X 12 inches, projecting down 2 feet 9 inches from the 
ceiling. It is placed about ten inches from the chimney, and 
opens into the attic at the floor level. There is, also, an 
opening about 8x10 inches into the chimney-flue at the floor, 
closed by an iron door, which is often left open, but not 
always, for sometimes it spoils the draught of the stove and 1888.] 
VENTILATION OF SCHOOL-ROOMS. 
333 
JACKSON STREET SCHOOL HOUSE LOWER ROOM 334 
STATE BOARD OF HEALTH. 
[Jan. 
lets gas into the room. The windows, furnished with boards 
placed under the lower sashes, are used as inlets. 
In the upper room there is a wooden duct 9x12 inches, 
running up close alongside the chimney, and discharging 
into the attic at the floor level. There is, also, a hole in the 
ceiling about 15 inches square, letting air into the attic. The 
attic has a wooden duct 14 X 16 inches, running through the 
ridge of the roof, and projecting down into the attic about 
two feet. This duct has a board across the top, and four 
small openings at the side. 
The window boards are used as in the lower room. 
Teachers have general directions, as in all the schools, to 
ventilate at recess, and in other ways to keep the air of the 
rooms as pure as possible without endangering the health of 
the pupils by exposing them to cold draughts, or to an 
unreasonably low temperature. A study of charts F and G 
with the accompanying tables will show how extremely 
unsatisfactory the ventilation of this building is. It is not 
too much to say that at the close of school and just before 
recess the air becomes horribly foul. 
George Street Schoolhouse. 
This building is made on the same general plan as the 
above. Each room has a separate wooden duct running up 
by the side of the chimney, the two combining in the attic, 
turning at right angles three times, and going out through 
the roof about six feet from the chimney. The duct from 
the lower room is 7 X 20 inches, that from the upper room 
X 21 inches. Into each duct there are two openings, one 
at the top and the other at the bottom of the room, each 
10 X 14 inches, with hinged doors. The windows are sup- 
plied with boards as at the Jackson Street schoolhouse. 
Charts H and I, with the tables, set forth the results of 
observations and emphasize the remarks in the preceding 
section. 1888.] 
VENTILATION OF SCHOOL-ROOMS. 
335 
GEORGE STREET SCHOOL HOUSE LOWER ROOM 336 
STATE BOARD OF HEALTH. 
[Jan. 
General Observations. 
The Charts. - The charts are modelled after those of 
Professor Rietschel, of Berlin.* They show the number of 
pupils, amount of carbonic acid, relative humidity, temper- 
ature in degrees Fahrenheit, and time. On the opposite 
page the observations which form the basis of the charts are 
given in tabular form, together with notes that fully set 
forth all the conditions. 
The Test of Purity. - In obtaining the samples of school- 
room air for analysis the instructions of Professor Hills were 
followed. Large bottles with tightly fitting rubber stoppers 
were used. The bottles were filled by means of a pair of 
bellows, with a long piece of rubber tubing attached to the 
nozzle. Except as otherwise specified the samples were all 
taken in the middle of the room, and at the breathing 
line of the pupils. The bottles were sealed and carried at 
once to the laboratory of the Harvard Medical School, 
where the determinations were made. 
It needs but a glance at the charts to show the wide 
differences between the ventilated and the unventilated 
school-rooms. The results here given are in entire accord- 
ance with those of other observations previously made under 
the direction of the school committee of Lynn, and with 
the evidence derived from the senses. 
It may be stated by way of explanation to those who have, 
perhaps, given less study to the subject than the writer, 
that the standard of purity set up by the highest authorities 
(Dr. Parkes, Angus Smith, DeChaumont and others) is that 
of six, or, at the most, eight parts of carbonic acid in 10,000 
volumes, of air. When the amount is ten parts or more the 
impurity becomes manifest to the senses. Some writers 
contend that in school-rooms it is not practicable, usually, 
to keep the amount of carbonic acid much below ten, on ac- 
count of the large number present and the limited air space. 
Ten should certainly be regarded as the extreme upper limit. 
We may say, then, that when the black line, representing 
the amount of carbonic acid in the charts, keeps below six 
* Luftung und Heizung von Schulen. Berlin, 1886. 1888.] 
VENTILATION OF SCHOOL-ROOMS. 
337 
the ventilation is perfect; when it rises above six, but does 
not go above eight, it is good; when it rises above eight, but 
does not go above ten, it is fair; when it rises above ten, it 
is bad in proportion to the amount of carbonic acid shown 
to be present. 
Let it be observed that in the four charts based on obser- 
vations made in the unventilated rooms the carbonic acid 
line very speedily gets above ten, even when it starts from a 
point near the line of atmospheric purity, as in chart I. 
In the case of chart II the tables and notes will show that 
there was an outflow from the ventilators of nearly 13,000 
cubic feet per hour; that the windows had been partially 
opened during the session, and that the air of the room had 
been pretty thoroughly changed at recess. In fact, the con- 
ditions here for ordinary "good ventilation," so called, were 
much better than the average. 
The result of the air analyses, as shown by the chart, fully 
bears out the opinion expressed on page 318, in regard to 
the inadequacy of the means commonly supplied for the ven- 
tilation of school-rooms. 
Attention is called to the fact that not infrequently the air 
samples taken just before or at the opening of school in the 
morning were shown to contain carbonic acid in decided 
quantity. This appears in charts A, C and H, and in some 
of the determinations not shown in the charts. The contam- 
ination without doubt arose from the fires, which were kept 
burning all night, the rooms, with all inlets and outlets, 
being closely shut up. The presence of carbonic acid in the 
amount indicated might not be of itself harmful; but when 
it is understood that carbonic acid escaping under such cir- 
cumstances into the room is almost certain to be accompanied 
by the deadly carbonic oxide, the matter is seen to be one 
of some importance. The observer noticed on one or two 
occasions the smell which indicates the presence of coal gas. 
It is plain that when fires are kept burning in a school- 
room all night, the air of the room should be completely 
changed in the morning before the opening of school. This, 
indeed, would not be a bad rule to follow under all circum- 
stances. The rapidity with which one of the ventilated 
rooms may be made to clear itself of air containing such 338 
STATE BOARD OF HEALTH. 
[Jan. 
impurities may be seen in chart A, where the black line start- 
ing from a point above eleven, runs sharply down to a point 
below five, in a space representing a little more than ten 
minutes. 
Humidity. -No attempt has been made to supply moist- 
ure to the air of the ventilated school-rooms, and there has 
been no complaint of discomfort from the dryness. In 
respect to the humidity of the air there is no material differ- 
ence between the ventilated and the unventilated rooms. 
To introduce air from out of doors, at the same time rais- 
ing its temperature thirty degrees or more, as is done in our 
school-rooms during a portion of the year, is to increase 
very largely its capacity for moisture, and to lower corre- 
spondingly its relative humidity, or percentage of satura- 
tion, which, inversely, is the measure of its drying power. 
An increase of 27° F. in the temperature of air doubles its 
capacity for moisture. 
An inspection of the tables given in connection with the 
charts will illustrate these statements, although an exact 
estimate of the change caused by a given rise in temperature 
is not possible, owing to a lack of precise correspondence in 
the times and places of observation. 
This great increase in the drying power of the air, which, 
owing to the necessity of heating it, is unavoidable, has been 
represented as an evil of considerable magnitude by some 
writers on sanitary subjects. Such appears also to be the 
popular belief. It is almost universally understood that to 
keep a shallow pan of water upon the top of a stove, for the 
purpose of supplying moisture to the air, is a wise pro- 
cedure. In regard to this point the writer agrees fully with 
Dr. Billings, who argues against the theory that simple dry- 
ness of the air is harmful, and expresses the belief that the 
ill effects usually ascribed to it arise in fact from a lack of 
sufficient ventilation, from a contamination of the air with 
carbonic oxide, or from overheating. In regard to the ne- 
cessity and practicability of supplying moisture by artificial 
means he uses the following language : - 
"It is evident, therefore, that it is not necessary to sup- 
ply moisture enough to heated air to bring the percentage 
up to 70. It is also to be noted that it will take about the 1888.] 
VENTILATION OF SCHOOL-ROOMS. 
339 
same amount of fuel, or, in other words, will cost as much to 
furnish this percentage of moisture to air heated from 32° 
F. to 70° F. as it does to heat the air. Moreover, in a room 
properly ventilated, under such circumstances, it would be 
practically almost impossible to maintain such a percentage 
of moisture, owing to the great rapidity with which the 
vapor of water diffuses in such a dry air, and the con- 
densation which would occur on windows and thin outer 
walls."* 
Temperature. - The fear has been expressed that when 
supplying so much fresh air it would be found difficult 
to keep up the heat, or to diffuse it uniformly through the 
room. This would doubtless be the case if only one stove 
were used; but with two, the experience in Lynn has proved 
that there need be little trouble even in the coldest weather. 
The temperature lines of the charts are based on observa- 
tions taken at the breathing line of the pupils, and at such 
times as to accentuate the changes produced by the opening 
of doors in the morning and at recess. In the tables which 
follow, two of the ventilated are compared with two of the 
unventilated schoolhouses. To make the comparison exact 
the observations should have been taken on the same day, 
and under precisely similar conditions. This was not possi- 
ble with one observer, and limited time for the work. The 
thermometers in the front of the room were in all instances 
placed as far away from the stoves as practicable, in order to 
avoid the effect of the direct heat. In the ventilated rooms, 
as there are two stoves in front, the thermometers could 
not be placed so far away from them as in the unventilated 
rooms. For this reason the most marked inequalities of 
temperature in the unventilated rooms are not exhibited in 
the tables, and the differences between the front and the rear 
are made to appear less relatively than they really are. 
In all the tables allowance should be made for the low 
temperature shown at 9 and 10.30 o'clock, particularly on 
the very cold days. It is accounted for by the entrance of 
cold air through open doors at the opening of school and at 
recess. 
*The Principles of Ventilation and Heating, and their Practical Application. 
By John S. Billings, M.D., LL D. (Edinb.), Surgeon U. S. A. New York, 1884. 
Page 59. 340 
STATE BOARD OF HEALTH. 
[Jan. 
Red Rock Street Schoolhouse, Lower Room, March 5, 1888. 
©too 
5 r-* to 
Ft. In. 
Heights 
above floor. 
a 
B 
56.5 
60 
85 
Front. 
peratu 
1 1 1 
Rear. 
© 
© 
re outs 
60 
67.5 
91 
Front. 
c 
CL 
*1 O 
© 00 
Rear. 
OS 
O 
CO © 
LO © H- 
O' 
Front. 
Stro 
-1 03 © 
©O' © 
Rear. 
© 
ag nor 
QO © © 
O' 
Front. 
M 
© 
-1 03 03 
03 O' © 
Rear. 
W 
© 
* 
B* 
sag 
O' 
Front. 
-1 03 03 
03 © IO 
© O' O' 
Rear. 
© 
(X 03 03 
Front. 
M 
ass 
Rear. 
© 
0 
2 
71 
65.5 
71 
68 
67 
67 
65.5 
66 
63 
64 
65 
65 
2 
11 
73.5 
71.5 
74 
72.5 
70 
69.5 
68 
68.5 
65.5 
66 
67 
67.5 
10 
4 
83.5 
81 
80 
78 
74 
72.5 
70.5 
70 
67 
68 
74 
72 
Red Rock. Street Schoolhouse, Upper Room, Feb. 25, 1888. 
Cloudy day. Wind from southeast, brisk. Temperature outside, 35®. 
Jackson Street Schoolhouse, Lower Room, Feb. 27, 1888. 
0 
2 
56 
52.5 
59 
55 
60 
56 
52.5 
53.5 
61 
56.5 
65 
60 
2 
11 
61 
59 
64 
62 
65.5 
63.5 
56.5 
56 
68.5 
65 
74 
70 
10 
4 
77 
71.5 
76.5 
72 
78 
73 
78.5 
73.5 
87.5 
82.5 
88 
83 
Clear day. Light westerly wind. Temperature outside, 14' to 16®. 
George Street Schoolhouse, Lower Room, March 6,1888. 
0 
2 
49 
49 
56 
53 
56.5 
56 
49.5 
48 
56 
56 
56.5 
56 
2 
11 
56 
57 
67.5 
63.5 
67 
65 
58.5 
53 
66 
61.5 
65 
63 
8 
7 
76 
75 
79 
76 
73.5 
80 
79 
75 
74 
73 
72 
Cloudy day. Light westerly wind. Temperature outside, 20® to 26®. 
George Street Schoolhouse, Upper Room, Feb. 28, 1888. 
0 
2 
55.5 
51 
59 
53.5 
61 
55.5 
53.5 
49.5 
64 5 
58 
61 
56 
2 
11 
63 
58.5 
64 
61 
65.5 
62 
58 
54.5 
69.5 
66 
66.5 
63.5 
10 
4 
79 
72 
74 
70 
74.5 
70 
74 
70 
83 
78 
78 
74 
Light wind. Temperature outside, 14® to 16®. 
Chase Avenue Schoolhouse, Lower Room, March 14, 1888. 
0 
2 
59 
57.5 
63 
60 1 
63.5 
61 
63.5 
60 
67.5 
63.5 
65.5 
63 5 
2 
11 
63.5 
62 
67 
61.5 | 
66.5 
65 
68.5 
65 
72 
68.5 
68.5 
67.5 
10 
4 
72 
70 
» 
71.5 
69 
83 
77 
83 
78 
72 
70 
Cloudy and snowing. Light wind from northeast. Temperature outside, 36° to 38*. 1888.] 
VENTILATION OF SCHOOL-ROOMS. 
341 
Schoolhouses - Average Temperatures 
George Street, upper 
room, Feb. 28, 1888, 
Red Rock Street, upper 
room, Feb. 25, 1888, . 
Chase Avenue, lower 
room. March 14,1888, 
George Street, lower 
room, March 6, 1888, 
Jackson Street, lower 
room, Feb. 27, 1888, . 
Red Rock Street, lower 
room, March 5, 1888, 
Ci 
p 
o 
p 
Cl 
to 
CH 
05 
Cl 
Ci 
Temperature at 
floor. 
> 
C' 
bi 
W 
bi 
05 
05 
w 
s 
g 
g 
£ 
g 
03 
Temperature at 
CO O 
£ s 
L- o 
b> 
bi 
io 
bo 
to 
breathing line. 
to 
o 
C' 
GO 
p 
81.9 
Temperature near 
ceiling. 
S o 
p t? 
Difference between 
S 2 
p 
w 
to 
Cl 
*• 
p 
p 
p 
>-» 
floor and breath- 
ing line, front of 
room. 
§ i 
Difference between 
5? 
co 
03 
bi 
00 
-4 
floor and breath- 
ing line, rear of 
AKE 
0 11 
room. 
o 
Difference between 
* s 
C3 
to 
00 
Ci 
rfs* 
floor and breath- 
co 
>-* 
co 
to 
C0 
lug line, for whole 
room. 
GO 
g 
8 
O1 
Cl 
Cl 
CO 
03 
Temperature at 
bl 
to 
bo 
J-* 
CO 
floor. 
p 
p 
o 
Ci 
Cl 
C» 
Temperature at 
•4 
p 
if. 
to 
p 
b> 
bi 
breathing line. 
ojo 
oo 
oo 
Temperature near 
O' 
p 
05 
4- 
p 
ceiling. 
to 
05 
<0 
>-* 
b> 
pj » 
A comparison of the above tables with the statement of 
averages and differences which follows will convince any one 
that, so far as heating is concerned, the advantage is de- 
cidedly with the ventilated school-rooms. Were the tem- 
perature within eight or ten feet of the unjackctcd stoves 
shown, this advantage would be still more plainly manifest. 
The character of the weather should in every instance be 
considered. Aside from the temperature, it is much more 
difficult to keep a building warm on windy than on quiet 
days. Compare the lower room of the Bed Kock Street 
schoolhouse with that of the George Street schoolhouse. 
The outside temperature was nearly the same on the days 
when the observations were made. In the case of the former 
the floor temperature averages 61.3°; of the latter 53.5°, 
a difference of 7.8°. The difference between the floor and 
breathing line is 3.8° greater at the George Street than at 
the Red Rock Street schoolhouse. A comparison of any 
one of the ventilated with one of the unventilated rooms 
in the above table would give similar figures. 
The Baltimore Street schoolhouse is to be considered by 
itself. The numerous observations which have been made 
are shown in the following tables : - 
* Including observations at opening of school and at recess. 342 
STATE BOARD OF HEALTH. 
[Jan 
Baltimore Street Schoolhouse, Lower Room, Feb. 13, 1888. 
Heights 
above floor. 
0.00 
9.30 
10.00 
10.30 
11 
00 
11 
.30 
Ft. 
In. 
a 
C8 
fl 
c5 
a 
s 
fl 
C3 
c 
s 
A 
o 
3 
Ph 
M 
Pa 
Ph 
Pa 
« 
PS 
Pa 
ci 
Pa 
M 
0 
2 
51.5 
51 
57.5 
56 
59.5 
58.5 
57 
59 
59.5 
59.5 
61 
61 
2 
11 
61.5 
63 
69.5 
71 
70.5 
73.5 
67 
69.5 
69 
72.5 
70 
74 
10 
4 
78 
81 
87 
94 
80.5 
83.5 
77.5 
80.5 
77 
82.5 
77 
82.5 
Clear day. Wind from north, fresh. Temperature outside, 7° to 18*. 
Baltimore Street Schoolhouse, Feb. 18, 1888. 
O bO © 
- tO 
Ft. In. 
Heights 
above floor. 
© o © 
Lower Room 
front. 
OO -l © 
»-* bo to 
Upper Room 
front. 
© 
© 
•4 O) C3 
** © QO 
Lower Room 
front. 
© 
© © 
to <£> co 
Upper Room 
front. 
b 
© 
59 
65.5 
71 
Lower Room 
front. 
© 
62 
66.5 
67 
Upper Room 
front. 
© 
© 
00 tO 
Lower Room 
front. 
© 
59 
63.5 
71 
Upper Room 
front. 
b 
© 
00 o on 
bo © © 
Lower Room 
front. 
M 
61.5 
70 
87 
Upper Room 
front. 
© 
© 
60 
68.5 
74.5 
Lower Room 
front. 
1 co3 
Upper Room 
front. 
b 
c 
Clear-cloudy. Wind from northwest, fresh. Temperature outside, 25° to 35®. 
Baltimore Street Schoolhouse, Feb. 23, 1888. 
0 
2 
58 
61.5 
61 
63 
61.5 
65 
47 
64 
58 
66 
59 
65.5 
2 
11 
69 
66 
73 
67.5 
72.5 
69.5 
63.5 
68.5 
68 
71 
69 
69 
10 
4 
78 
69.5 
81 
73 
76.5 
77 
73 
83 
72.5 
77 
74 
71 
Morning opened clear and became cloudy. Light wind from west. Temperature out- 
side, 29® to 38®. 
Baltimore Street Schoolhouse - Average Temperatures. 
Lower room, Feb. 
13,1888, . 
Lower room, Feb. 
18, 1888 (obser- 
vation in front 
only), 
Lower room, Feb. 
23, 1888 (obser- 
vation in front 
only), 
Upper room, Feb. 
18 (front only),. 
Upper room, Feb. 
23 (front only),. 
O © Cm cm cm 
P r4 r1 
to co 4- to © 
Temperature at floor. 
Averages of Observations taken 
at 9,9.30,10.00,10.30,11.00 and 11.30.* 
© © © © © 
00 © © -CM © 
© to 03 CO 
Temperature at breath- 
ing line. 
"4 "4 "4 -4 00 
CM CM CM CM 1-' 
>-1 © 00 "4 GO 
Temperature near 
ceiling. 
**■ © P P 
4- © bo to to 
Difference between 
floor and breathing 
line, front of room. 
III 1 « 
»-* 
Difference between 
floor and breathing 
line, rear of room. 
III 1 !■* 
•4 
Difference between 
floor and breathing 
line, for whole room. 
© © CM CM CM 
4- 03 CO OO CO 
CO 4- CO CO U 
Temperature at floor. 
Averages of Observations taken 
at 9.30,10.00,11.00, and 11.30. 
Ci Ci "4 Ci *4 
© © © -4 h-» 
CO © Ci CO 
Temperature at breath- 
ing line. 
-1-4-1 -4 00 
4- CM © CM 03 
CM CO 4- 
Temperature near 
ceiling. 
4* © © 00 © 
4* 03 © OO 4*- 
Difference between 
floor and breathing 
line, front of room. 
iii i £ 
Difference between 
floor and breathing 
line, rear of room. 
111 ' £ 
Difference between 
floor and breathing 
line, for whole room. 
* Including observations at opening of school and at recess. 1888.] 
VENTILATION OF SCHOOL-ROOMS. 
343 
It must be admitted that in some respects the showing 
in the case of the lower room is not as favorable as with the 
other ventilated rooms, for the floor temperature is too low, 
and there is much too great a difference between this tem- 
perature and that of the breathing line. 
But notwithstanding this the floor is, as a rule, several 
degrees warmer than the floors of the unventilated rooms, 
while it is warm enough at the breathing line. In all other 
respects this building compares favorably with the others. 
The fault with it is undoubtedly one that has been before 
alluded to, viz. : that, owing to defect in structure, cold air 
is admitted by channels not provided for it, keeping the 
floor cold. The defect is one which a carpenter can remove. 
The fact that the floor temperature in the front of the 
room is, on the average, higher than that in the rear, seems 
to prove that the position of the stoves has nothing to do 
with the difficulties experienced. 
Air-Meter Tests.- These were all made with one of Cas- 
ella's anemometers, the accuracy of the instrument having 
been determined by comparison with the one in use at the 
United States Signal Service Station in Boston. 
Where circumstances are favorable, as at the Red Rock 
Street and the Baltimore Street schoolhouses, it is easy to 
ascertain with substantial accuracy the air supply, by meas- 
uring the outflow. Where the outlets are numerous and 
scattered but little reliance can be placed upon this test. 
In the unventilated rooms the air movements are so varia- 
ble that, usually, no determination of outflow or inflow can be 
made. The observations taken at the George Street school- 
house, lower room, on March 24, 1887, are exceptional, and 
probably show very nearly the true air supply of the room. 
Those taken in the upper room on the same date evidently 
show a result which falls far below the reality. 
It is satisfactory to note a general correspondence between 
the results of the air-meter tests and those of chemical 
analysis, as thus they become mutually confirmatory. For 
instance, in the Red Rock Street schoolhouse, lower room, 
where the supply is shown to be very large, the chemical 
tests prove that the air is practically as pure as that out of 344 
STATE BOARD OF HEALTH. 
[Jan. 
doors, while in the upper room, where the supply is less 
(the pupils also being older), the air is shown to be less 
pure, although the amount of carbonic acid comes well within 
the limits ascribed to good ventilation. 
Advantages of the System. -The advantages of this sys- 
tem of heating and ventilating school-rooms may be briefly 
summarized as follows : - 
1. It is extremely simple, and can be easily applied to 
that large class of school buildings which it is convenient or 
practicable to heat by stoves only. 
2. When the conditions of success are observed, it is 
possible to secure perfect, or nearly perfect, ventilation by 
this method. 
3. The position of the stoves in the school-room prevents 
any waste of heat. When arranged as at the Red Rock 
Street schoolhouse the whole apparatus is under the imme- 
diate supervision of the teacher, who can attend to it without 
leaving the room. 
4. The heating of the rooms is more satisfactory than 
with the unjacketed stove, or the hot-air furnace. The 
disadvantages of the stove, as commonly used, are well 
known. No provision is made for a supply of fresh air, and 
the temperature is very unequal in different parts of the 
room. The ordinary furnace supplies a small amount of 
highly heated air. When the heat becomes too great, regis- 
ters arc closed, and the fresh air supply, what there is of it, 
is thus shut off*. By the jacketed stoves, as used in Lynn, a 
large amount of moderately heated air is furnished, and 
there is little danger of over-heating. The jackets around 
the stoves protect those sitting near from the direct or 
radiant heat. 
Expense of the System.-This includes the cost of con- 
struction and of maintenance. The cost of the improve- 
ments at the Red Rock Street schoolhouse was $567.77 ; of 
those at the Baltimore Street schoolhouse, $554.56. At the 
Chase Avenue schoolhouse $418.16 was originally expended, 
but subsequent changes considerably increased the cost. 
Quite a large part of the first cost came from the necessary 1888.] 
VENTILATION OF SCHOOL-ROOMS. 
345 
tearing down and building up again. It is notoriously 
expensive to make changes in completed buildings. The 
schoolhouse mechanic, who has had a general oversight of 
the work of making these improvements, estimates that if 
put in during the process of construction the apparatus in 
a two-room building would not cost more than $350 ; in a 
one-room building $225. The changes could probably be 
made in fin old one-room building for $350. When the 
arrangements form part of the original plan of a school- 
house, they arc likely to be much more satisfactory than 
when added afterwards. 
The cost of maintenance involves an increased outlay for 
janitor service and for fuel. In country districts where the 
fires arc cared for by the voluntary service of teacher and 
pupils the former item is not to be reckoned. In Lynn an 
extra allowance of fifty cents per week for each additional 
stove is made during the season when the fires are in opera- 
tion. This amounts to something near $40 per year for each 
building of two rooms. 
From our experience thus far it is difficult to form an 
exact estimate of the increased cost of fuel. The coal and 
wood are supplied to the city on contract, the bins being 
filled up when necessary. It is certain that the consump- 
tion of fuel increases somewhat in.proportion to the amount 
of fresh air supplied. At the Chase Avenue schoolhouse, 
as nearly as can be ascertained, from five to six tons more 
of coal have been burned each year since the ventilating 
apparatus was put in than before. It would be not far 
from the truth if we should reckon the increased cost of 
fuel for the building at $30 per year, or $15 for each room. 
This added to the increased outlay for janitor service makes 
$35 per room, - surely not an extravagant sum to pay for 
anything so necessary to health as pure air. 
The Conditions of Success.- 1. The first point to be 
mentioned under this head is that the building should be of 
good construction. It is not uncommon for schoolhouses to 
admit air freely, not only around doors and windows, but 
even directly through the walls. Such a defect in structure 
is a serious obstacle to the success of this plan of heating 346 
STATE BOARD OF HEALTH. 
[Jan. 
and ventilating. Brick is a better material for walls than 
wood, because it is not so good a conductor of heat. In the 
case of wooden buildings a layer of tarred paper under the 
clapboards and back-plastering the walls are suggested as 
expedients for keeping air out and heat in. Double win- 
dows, or windows with double frames, might be used. 
Floors should be double and well laid. The underpinning 
should be tight, and there should be no dampness under the 
building. When an old schoolhouse is to be ventilated in 
this way, a few hundred dollars might, in many instances, be 
profitably spent in the direction indicated above. 
2. The extraction flues should be of a size proportionate 
to the amount of air to be removed. Those at the Red 
Rock Street schoolhouse are suggested as models. In order 
to produce a satisfactory draught in them it is necessary 
that they receive a larger amount of heat than that derived 
from the smoke pipes. If a stove be used for this purpose, 
as in Lynn, it should be set into the partition between the 
flues in such a way as to supply an equal amount of heat to 
each. The partition between the flues should be made tight 
around the stove. When the fire is in operation the door 
into the chimney should be kept shut. Other methods 
of heating the flues might be used,- a gas-jet, for instance. 
The experiment of using kerosene-burners at the Chase 
Avenue schoolhouse was abandoned on account of the disa- 
greeable smell produced. 
3. The foul air should be discharged into the flue at the 
bottom, or at any rate below the place where the flue-heat- 
ing stove or burner is placed. The attempt at the Chase 
Avenue schoolhouse to produce a draft by applying heat at 
the bottom of the flues, while the foul air was let into them 
at the floor level of the rooms, did not prove satisfactory. 
Indeed, a theoretical study of the problem might have shown 
that this was likely to be the case; for such an arrangement 
would necessitate an ascending and a descending current of 
air, with more or less of irregular movement and conflict, 
in the lower part of the flues. 
4. The combined area of the outlets from the rooms 
into the flues, making allowance for registers, wire netting 
and other means of obstruction, should be somewhat greater 1888.] 
VENTILATION OF SCHOOL-ROOMS. 
347 
than that of the extraction flue on cross section. They 
should open as directly as possible into the flue, or into the 
duct leading to it. To take the foul air from numerous 
openings, or from different parts of the room, materially 
impedes the outflow, while it does not appear to aid in the 
distribution of the pure air. 
5. The stoves should be situated near the sides of the 
building, in order that it may not be necessary to convey 
the cold air for a long distance under the floor. To do this 
would be to produce more or less coldness of the floor, an 
evil to be avoided. 
6. The inlets should each be large enough for the total 
air supply of the room, so as to be sufficient when only one 
stove is in use. The space within the jacket, around the 
base of the stove, should be equal to the inlet. No air-duct 
can be considered larger than its smallest part. 
7. Lastly, teachers and janitors should be thoroughly 
instructed in regard to the working of the apparatus. Any 
scheme of ventilation will prove a failure if not intelligently 
managed. 348 
STATE BOARD OF HEALTH. 
[Jan. 
09 
11.18-30 
o 
10.50-11.05 
10.30-37, .... 
10.05-20, .... 
9.55-10.00, .... 
9.20-35 
9.00, 
8.50-53 
8.37-40 
M 
Number of per- 
o* 
o» 
tn 
- I 
o» 
00 
On 
QO 
C3 
QO 
s 
Ci 
s 
to 
sons present. 
g 
69.5 
63.5 
1 
co 
00 
66.5 
O 
in 
1 
o 
C3 
Air temperature 
(Fahrenheit). 
w 
CD 
1 
s 
io 
1 
1 
CO 
►-* 
1 
to 
o 
Humidity of air 
(percentage of 
complete satu- 
ration). 
«5 
►-* 
Carbonic acid in 
QO 
1 
i 
1 
c> 
to 
o 
1 
1 
1 
i-2 
to 
Ci 
air (parts in 
10,000). 
1 
120,060 
• 
122,940 
1 
1 
C0 
O 
8 
113,700 
1 
1 
1 
Discharge of air 
from room (cu- 
bic feet per 
hour). 
Minutes taken 
1 
Ci 
1 
en 
1 
1 
-» 
o 
1 
1 
1 
to discharge a 
roomful. 
X 
1 
1 
1 
s 
1 
1 
1 
CO 
O 
I 
to 
o 
Temperature out 
of doors. 
Red Rock Street Schoolhouse, Loicer Room, March 7, 1887. 
* Mean of two measurements. f About. 
Clear day. Wind from northwest, fresh. 
At Water Office, 8 a.m. -Barom., 30.33; D. B., 26.5; W. B.,25.5; Humid., .88. 
« " 1 P.M. -Barom., 30.31; D. B., 32.0; W. B., 30.5; Humid., .83. 
Red Rock Street Schoolhouse, Lower Room, March 7, 1887. 
T I M E. 
8.40, . 
Foul air outlets all open. Fresh air inlets closed. 
8.45, . 
Scholars came in. Teacher opened inlets one-half each. 
8.50, . 
Inlets opened wide. 
9.20-33, . 
Air currents measured at all outlets. Rate of discharge, 113,700 cubic feet 
per hour, or the roomful in six minutes. 
9.40, . 
Standing by northwest stove-jacket observer felt cool air on his head. Fire 
low. Same at southeast jacket. 
9.43, . 
Calisthenics. Teacher opened northwest window, near door, also both 
doors into entry. Observer half-closed both inlets. 
9.45, . 
Windows and doors closed. 
9.55, . 
Measurements at two outlets indicated a discharge of about 94,000 cubic feet 
per hour, or the roomful in about seven minutes. 
10.20, . 
Recess begun. Three scholars stayed in. Draft of ventilating apparatus 
increased. Both inlets opened wide. 
10.40, . 
Recess ended. 
10.55, . 
Measurements at all outlets. Rate of discharge, 122,940 cubic feet per hour, 
or the roomful in five minutes. 
11.10, . 
Half-closed both inlets. Quickened fire in northwest stove a little. 
11 18-30, . 
Measurements at all outlets: rate of discharge, 120,060 cubic feet per hour, 
or the roomful in six minutes. 
11.45, . 
School dismissed. 
Contents of room, 11,700 cubic feet. Airspace for each of 67 scholars, 160 cubic feet. 
Average age of scholars, 7 years, 9 mouths. A 
RED ROGK STREET SCHOOL HOUSE LOWER ROOM 
Observations March 7™ 1887 
Carbonic ,7/cuf in Jhcre- otvr, -parts in /(JOOO 
" " parts tn 1OOOO 
/fetatstve /furissOJp 
1'empera/susr& 
vn schools rooms 
Aarnber of sc/iolcora present' B 
RED ROGK ST. SCHOOL HOUSE UPPER ROOM 
February 25™ 1888. 
" " parte in /OOOO 
. Relative Jtunititilp. 
. Temperature 
. Cardontc in Pure 'rlir, parte in /(WOO 
tn- school/ room/ 
-Number of scholars /ore sent 1888.] 
VENTILATION OF SCHOOL-ROOMS. 
349 
Red Rock Street Schoolhouse, Upper Room, Feb. 25, 1888. 
12.07, 
11.45, 
-4 
jo 
11.30, 
H-1 
JJO 
11.00, 
10.50, 
10.45, 
10.40, 
10.30 
10.15-20 
10.00 
9.45-50, 
© 
CO 
© 
9.00 
CO 
TIME. 
Number of per- 
Cl 
O' 
O' 
O' 
O' 
O' 
O' 
O' 
O' 
CJ I 
1 
IO 
to 
to 
to 
to 
to 
>-* 
to 
to 
to 
to 
to 
to 
>-* 
sons present. 
© 
© 
© 
© 
© 
© 
© 
© 
Air temperature 
1 
to 
© 
O' 
© 
1 
© 
© 
GO 
© 
© 
O' 
© 
CO 
to 
O' 
co 
(Fahrenheit). 
Humidity of air 
co 
co 
co 
4- 
CO 
co 
(percentage of | 
1 
55 
1 
© 
© 
1 
Cl 
1 
to 
to 
© 
© 
55 
© 
< 
complete satu- 
• 
ration). 
Carbonic acid in 1 
1 
I 
1 
1 
1 
1 
1 
© 
1 
r' 
1 
1 
1 
1 
O' 
air (parts in 
© 
to 
♦ 
co 
© 
* 
10,000). 
g 
Kate of disch'ge 1 
© 
from outlets 
1 
1 
I 
1 
1 
1 
1 
1 
1 
1 
1 
4- 
1 
1 
1 
(cubic feet per 
o 
GO 
hour). 
co 
Temperature out 
© 
I 
I 
1 
• 
1 
I 
1 
1 
1 
1 
1 
1 
1 
I 
O' 
of doors. 
, * Mean of two samples. 
Wind from northwest, fresh. 
Offlceof Water Board, Feb. 25, 8 a. m. - Barom., 30.16; D.B., 35; W. B ,33.5; Humid., 73. 
" " " " 1P.M. - Barom., 30.00; D.B., 36; W. B.,34.5; Humid., 84. 
Red Rock Street Schoolhouse, Upper Room, Feb. 25, 1888. 
TIME. 
.... - ........ ... . ... 
6.45, . 
Inlets closed; outlets open. 
6.50, . 
Inlets opened. 
7.05, . 
Fire built in chimney stove. 
Six windows opened from ten to twenty inches. 
8.25, . 
8.35, . 
Windows closed. 
8.43, . 
Air samples taken in two places in room. 
8.48, . 
Scholars came in. 
9.50, . 
Air-meter measurements in outlets: indicated discharge, 89,478 cubic feet 
per hour. 
10.18, . 
Air samples taken as before. 
10.23, . 
Recess began. 
10.39, . 
Air samples taken as before. 
10.44, . 
Scholars came in from recess 
10.50, . 
Air meter measurements in outlets : indicated discharge, 90,720 cubic feet 
per hour. 
11.40, . 
Air samples taken as before. 
11.46, . 
School dismissed. 
Contents of room, 12,040 cubic feet. Air apace for each of 66 scholars, 162 cubic feet. 
Average age of scholars, 9 years, 6 months. 350 
STATE BOARD OF HEALTH. 
[Jan. 
11.53 
11.35-40 
10.55 
10.37-40, .... 
10.30 
10.15, 
9.40, 
9.30 
8.35-38, .... 
TIME. 
Number of per- 
to 
H-* 
to 
to 
to 
to 
to 
to 
sons present. 
o> 
© 
co 
1 
8 
o 
1 
t 
1 
o> 
-1 
Air temperature 
• 
O' 
(Fahrenheit). 
Humidity of air 
03 
to 
to 
to 
(percentage of 
CO 
co 
1 
1 
1 
complete satu- 
ration). 
co 
►u 
GO 
CO 
Carbonic acid in 
1 
O 
1 
03 
1 
1 
1 
1 
QO 
air (parts in 
© 
03 
os 
CO 
10,000). 
8 
Rate of discharge 
1 
1 
1 
1 
1 
1 
1 
8 
1 
1 - 
at outlet (cubic 
feet per hour). 
Minutes taken 
1 
1 
1 
1 
1 
1 
1 
1 
1 
to discharge 
the roomful. 
o 
03 
oo 
03 
Ci 
1 
03 
O' 
1 
C-3 
1 
8 
1 
Temperature out 
O' 
of doors. 
Chase Avenue Schoolhouse, Lower Room, March 31, 1887. 
Clear day. Wind from north northwest, strong. 
At Water Office, 8 a.m. - Barom., 29.93; D. B., 25.5; W. B., 22.0; Humid., .56. 
" " 1 p.m. - Barom., 30.00; D. B., 39.0; W. B., 36.0; Humid., .73. 
Chase Avenue Schoolhouse, Lower Room, March 31, 1887. 
TIME. 
8.33, . 
Platform outlets all open. Inlets partly open. Two fires burning. Teacher 
opened both inlets wide. 
8.50, . 
Scholars came in. 
9.40, . 
Air currents at platform outlets measured : rate of discharge, 29,760 cubic 
feet per hour, or the roomful in twenty-one minutes. 
10.25, . 
Recess began. 
10.30, . 
Teacher opened southeast (leeward) window, lower sash, about two feet. 
10.35, . 
Pound fire in chimney stove low, and replenished it. 
Teacher closed window to within three inches of bottom. 
10.40, . 
10.50, . 
Recess ended. Window fully closed. 
11.05, . 
Quickened fire in chimney stove. Observed that mortar had fallen out of the 
partition between fines, at the stove, leaving a space about 24 X 3 inches. 
11.42, . 
School dismissed. 
Contents of room, 10,400 cubic feet. Air space for each of 42 scholars, 248 cubic feet. 
Average age of scholars, 7 years, 5 months. c 
CHASE AVENUE SCHOOL HOUSE LOWER ROOM 
March 31ST 1887 
Carbonic o/cid in ficre ctfir, parte irv iOOOO 
" " parks ifv IOOOO\ 
Relative Jfu/miRUp.... 
Temperature' 
in school rooms 
Aiirnh&r o/'ioiTseint D 
BALTIMORE ST. SCHOOL HOUSE LOWER ROOM 
February 23? 1888. 
. Carbonic uv Pure otvr parts' tn. /OOOO 
" " parks irv /OOOO 
. /teZatire IPomidzC'i/ 
. 7'emperoOccr& 
vtv sc/mob roomy 
Aornfter of \sckolw3 present 1888.] 
VENTILATION OF SCHOOL-ROOMS. 
351 
Baltimore Street Schoolhouse, Lower Room, Feb. 23, 1888. 
S> 
O 
11.30 
11.05 
10.50 
10 37, 
10.30 
10.20 
10.15, 
10.00 
9.30, 
9.16 
9.02, 
OO 
8.40 
TIME. 
Number of per- 
CO 
O' 
tn 
O' 
O' 
O' 
O' 
O' 
O' 
O' 
to 
** 1 
-1 
00 
GO 
oo 
-■J 
-* 
CO 
CO 
CO 
CO 
CO 
co 
CO 
to 
sons present. 
Cl 
S 
Ci 
Ci 
Ci 
Cl 
Cl 
Cl 
Air temperature 
CO 
CO 
co 
00 
CO 
O' 
o 
O' 
>-* 
tO 
b» 
CO 
1 
co 
O' 
© 
(Fahrenheit). 
Humidity of air 
4t 
4- 
(percentage of 
O 
1 
o« 
oo 
1 
00 
1 
co 
Ci 
1 
4* 
co 
1 
O' 
O' 
1 
complete satu- 
ration). 
Carbonic acid in 
1 
-4 
1 
1 
1 
1 
O' 
1 
1 
-I 
1 
1 
I 
I 
■M 
air (parts in 
CO 
- 
►_i 
Ci 
H-* 
CO 
10,000). 
Ci 
Cl 
Rate of disch'ge 
po 
from outlets 
1 
1 
1 
• 
1 
1 
1 
1 
1 
1 
1 
>-* 
1 
1 
1 
(cubic feet pet 
to 
© 
hour;. 
w 
Temperature out 
1 
1 
1 
1 
1 
1 
1 
1 
1-' 
of doors. 
Morning opened clear and became cloudy. Wind from west, light. 
At Water Board Office, 8 a.M.- Barom., 30.24; D.B., 29.0; W. B., 24.0; Humid., .45. 
" " " 1 p.m.-Barom., 30.22; D. B., 38.5; W. B., 37.0; Humid., .86. 
Baltimore Street Schoolhouse, Lower Room, Feb. 23, 1888. 
TIME. 
6.35, . 
School-room completely shut up. 
6.45, . 
Fires quickened. Inlets and outlets opened. 
8.15, . 
Four windows opened from six to twenty-four inches. 
8.30, . 
Windows closed. 
8.40, . 
Took air sample. 
8.42, . 
Scholars came in. 
9.16, . 
Air-meter measurement at outlets: indicated discharge, 67,140 cubic feet 
per hour. 
10.15, . 
Took air sample. 
10.25, . 
Recess began. 
10.37, . 
Air sample taken. 
10.45, . 
Scholars came in from recess. 
10.50, . 
Air-meter measurements at outlets: indicated discharge, 68,712 cubic feet 
• 
per hour. 
11.20, . 
Twenty-one scholars dismissed, leaving thirty-five. 
11.40, . 
Air sample taken. 
11.46, . 
School dismissed. 
Contents of room, 10,860 cubic feet. Air space for each of 59 scholars, 184 cubic feet. 
Average age of scholars, 6 years, 8 months. 352 
STATE BOARD OF HEALTH. 
[Jan. 
Baltimore Street Schoolhouse, Upper Room, Feb. 23, 1888. 
11-43 
r 
to 
© 
10.40, 
10.30, 
9.30, 
9.02, 
00 
TIME. 
Number of per- 
© 
CO 
to 
to 
sons present. 
© 
© 
© 
© 
© 
© 
© 
© 
Air temperature 
1 
© 
1 
<- 
O' 
00 
bi 
- 
© 
O' 
1 
O' 
© 
to 
(Fahrenheit). 
Carbonic acid in 
O' 
1 
1 
1 
O' 
1 
© 
1 
1 
1 
1 
© 
1 
air (parts in 
© 
to 
2 
co 
10,000). 
O' 
© 
Rate of disch'ge 
© 
from outlets 
1 
1 
© 
1 
1 
1 
i 
1 
O' 
co 
1 
1 
1 
• 
(cubic feet per 
© 
© 
hour). 
co 
Temperature out 
1 
of doors. 
Morning opened clear and became cloudy. Wind from west, light. 
At Water Office, 8 a. m. - Barom., 30.24 ; D. B., 29.0 ; W. B., 24.0 ; Humid., .45. 
" " 1 p. M.- Barom., 30.22 ; D. B., 38.5 ; W. B., 37.0 ; Humid., .86. 
TIME. 
6.35, . 
Schoolhouse wholly shut up. Opened inlets and outlets (except top outlets). 
Quickened fires. 
8 13, . 
Opened four windows from six to twenty-four inches each. 
8.42, . 
Closed windows wholly. 
8.45, . 
Air sample taken in middle of room at breathing line. 
8.47, . 
Scholars came in. 
9.06, . 
One scholar came in. 
9.35, . 
Air-meter measurements at outlets: indicated discharge, 68,580 cubic feet 
per hour. 
10.20, . 
Air sample taken in middle of room at breathing line. 
10.25, . 
Recess began; two scholars stayed in. 
10.40, . 
Air sample taken; same place as above. 
10.45, . 
Scholars came in from recess. 
11.13-25, . 
Air-meter measurements at outlets: indicated discharge, 56,670 cubic fee 
per hour. 
11.20, . 
Twenty-one scholars dismissed, leaving thirty-five. 
11.43, . 
Air sample taken in same place as above. 
11.47, . 
School dismissed. 
Baltimore Street Schoolhouse, Upper Room, Feb. 23, 1888. 
Contents of room, 10,740 cubic feet. Air space for each of 42 scholars, 256 cubic feet. 
Average age of scholars, 9 years, 3 months. E 
BALTIMORE ST. SCHOOL HOUSE UPPER ROOM 
February 23? I8S8. 
Carbcviiv dlclch ttv Pure c/Pr, ~pcort<s iro /OOOO 
" " paj'Os Iro 16>C>C>6>\ 
. Temperature'j 
lu school /'com 
JViirriter of s eke fans pres-ejn# F 
JAGKSON STREET SCHOOL HOUSE LOWER ROOM 
Observations March 16th 1887 
C'arbonio oZcuL irv TIztk? e/tvr, parts iro /OOOO 
- " " parts ifb /OOOO 
Relative 2/urn/olity ' 
Terttpera/ure , 
vrv school rocrrro 
of scholars prese/t# 1888.] 
VENTILATION OF SCHOOL-ROOMS. 
353 
11.52 
11.39-42 
10.32-35 
10.12-15, 
10.03, 
9 45 
9.10 
00 
I 
TIME. 
co 
co 
O' 
O' 
O' 
O' 
Number of per- 
sons present. 
05 
05 
66.5 
05 
05 
05 
05 
Air temperature 
O' 
1 
05 
O' 
1 
O' 
00 
05 
(Fahrenheit). 
Humidity of air 
to 
(percentage of 
GO 
1 
1 
1 
1 
CD 
1 
co 
1 
complete satu- 
ration). 
Carbonic acid in 
1 
8 
1 
1 
O' 
CO 
1 
1 
1 
05 
air (parts in 
CO 
O' 
co 
10,000). 
co 
Temperature out 
O' 
1 
1 
1 
1 
1 
1 
of doors. 
Jackson Street Schoolhouse, Lower Room, March 16, 1887. 
Cloudy day; light wind. 
At Water Office, 8 a.m. - Barom., 29.97; D. B., 23.5; W. B., 21.5; Humid., .73. 
" " 1 p.m. -Barom., 29.97; D. B., 36.0; W. B., 32.0; Humid., .61. 
Jackson Street Schoolhouse, Lower Room, March 16, 1887. 
TIME. 
8.42, . 
School-room shut up completely. 
8.50, . 
Scholars came in. 
10.15, . 
Recess began. Doors and windows kept closed during recess, just as during 
the session. Scholars all went out. 
10.35, . 
Recess ended. 
10.58, . 
Eighteen scholars (beginners) went home. 
11.45, . 
School dismissed. 
Contents of room, 7,830 cubic feet. Air space for each of 52 scholars, 151 cubic feet. 
Average age of scholars, 6 years, 10 months. 354 
STATE BOARD OF HEALTH. 
[Jan. 
Jackson Street Schoolhouse, Upper Room, March 16, 1887. 
11.28-35 
11.00, 
o 
10.30 
10.05-10, 
9.40, 
p> 
00 
<L« 
p> 
TIME. 
C3 
C3 
cn 
Cn 
Number of per- 
ci 
Cl 
Ci 
CO 
Ci 
Cl 
Cl 
to 
sons present. 
ci 
O 
Cl 
Ci 
Cl 
Ci 
Cl 
Air temperature 
<© 
to 
b 
H-* 
c© 
oo 
b 
(Fahrenheit). 
Humiditv of air 
4_ 
CO 
(percentage of 
00 
1 
00 
1 
1 
1 
complete satu- 
ration). 
Carbonic acid in 
ci 
b 
1 
1 
to 
b 
b 
1 
1 
O' 
b 
air (parts in 
co 
o 
10,000). 
co 
co 
CO 
Temperature out 
1 
1 
of doors. 
Cloudy day ; light wind. 
At Water Office, 8 a. m. - Barom., 29.97 ; D. B., 23.5 ; W. B., 21.5 ; Humid., .73. 
" " 1 p. m. - Barom., 29.97 ; D. B.,36.0; W. B., 32.0 ; Humid., .61. 
Jackson Street Schoolhouse, Upper Room, March 16, 1887. 
TIME. 
8.45, . 
School-room completely shut up. 
8.50, . 
Scholars came in. 
10.12, . 
Recess began. Windows kept closed. Both doors into entry open. 
10.35, . 
Recess ended. Doors closed, leaving school-room again completely shut up. 
11.43, . 
School dismissed. 
Contents of room, 7,430 cubic feet. Air space for each of 56 scholars, 133 cubic feet. 
Average age of scholars, 8 years, 11 months. G 
JAGKSON STREET SCHOOL HOUSE UPPER ROOM 
Observations Margh 16™ 1887. 
Carbontc tiv jPut& .Sltr, parts in, /OOOO 
" " parts irr /OOOO 
l/ela/vve t/um/tli/y....................... 
7'enpti 'Mure 
' vrv •Schoo!' room 
Number of scholars present/ H 
GEORGE STREET SCHOOL HOUSE LOWER ROOM 
Observations March 24™ 1887 
Carbonic <Tlcicl vro JPur& </?w, parto tn, /(WOO 
" " parts tn/ (OOOO 
/teZaCire Zfumailtrp 
Temperature, 
vrv school room 
jVnml>er ofScholars jwesenfr 1888.] 
VENTILATION OF SCHOOL-ROOMS. 
355 
George Street Schoolhouse, IjOicer Room, March 24, 1887. 
? 
© 
1 
o 
10.15 
co 
M 
g 
cn 
o« 
CH 
CH 
Number of per- 
© 
© 
sons present. 
© 
© 
Air temperature 
© 
© 
1 
1 
co 
1 
t- 
to 
CH 
© 
(Fahrenheit). 
Humidity of air 
w 
Ca? 
co 
co 
(percentage of 
© 
CH 
1 
1 
co 
1 
1 
1 
complete satu- 
ration). 
CO 
© 
to 
© 
Carbonic acid in 
b_l 
1 
oo 
© 
1 
1 
1 
1 
air (parts in 
O 
© 
© 
10,000). 
Air discharge 
1 
1 
1 
1 
JO 
© 
1 
1 
1 
at outlets (cu- 
bic feet per 
_g 
g 
hour). 
Minutes taken 
1 
1 
1 
1 
© 
r-* 
to 
1 
1 
1 
to discharge 
the roomful. 
co 
CO 
CO 
co 
Temperature out 
co 
CH 
1 
1 
to 
1 
© 
© 
of doors. 
* Upper outlet. f Lower outlet, 
Clear day. Wind from west northwest, light. 
At Water Office, 8 a.m. - Barom., 29.76; D. B., 25.0; W. B., 22.5; Humid., .69. 
" " 1 p.M. - Barom., 29.78. D. B., 35.5; W. B., 33.0; Humid., .74. 
George Street Schoolhouse, Lower Room, March 24, 1887. 
TIME. 
8.50, . 
Scholars came in. Window by stove open three inches at bottom and one 
•inch at top. Two windows on northwest side and two on southeast side 
open one-half inch each at top. Upper and lower outlets wide open. 
9.10, . 
Teacher closed all the windows on northwest side. 
9.48-50, . 
Air current in upper outlet measured (both outlets being open): rate of 
discharge, 10,560 cubic feet per hour, or the roomful in forty-two minutes. 
9.50, . 
Window by stove closed at the bottom. 
9.57-58, . 
Air current in lower outlet measured (both outlets open) : rate of discharge, 
2,340 cubic feet per hour, or the roomful in one hundred and ninety-one 
minutes. 
10.17, . 
Recess began. Five scholars stayed in. 
10.25, . 
The five scholars went out. Teacher opened two rear northwest windows 
and one front southeast window. Poor open about half the time, during 
recess. 
10.35, . 
Teacher closed northwest windows, and left southeast windows open, about 
one inch each. 
10.53, . 
Recess ended. 
11.45, . 
School dismissed. 
Contents of room, 7,400 cubic feet. Air space for each of 56 scholars, 132 cubic feet. 
Average age of scholars, 7 years. 356 
STATE BOARD OF HEALTH. 
[Jan. 
George Street Schoolhouse, Upper Room, March 24, 1887. 
CO 
f 
co 
00 
11.10-17, .... 
10.30-33, .... 
10.00-09, .... 
9.33, 
TIME. 
8 
Number of per- 
8 
CO 
Cn 
C3 
to 
sons present. 
Air temperature 
s 
§ 
CO 
co 
>-* 
2 
(Fahrenheit). 
Humidity of air 
CO 
(percentage of 
1 
1 
t-* 
1 
H* 
1 
complete satu- 
ration). 
10 
to 
Cartionic acid in 
p 
<□> 
4* 
air (parts in 
to 
2 
a> 
C" 
10,000). 
Air discharge at 
1 
■g 
1 
1 
1 
1 
outlets (cubic 
o 
feet per hour). 
Minutes taken 
1 
1 
1 
| 
1 
to discharge 
the roomful. 
1 
co 
C-' 
co 
CO 
to 
8 
1 
Temperature out 
ot doors. 
Clear day. Wind from west northwest, light. 
At Water Office, 8 A. M. - Barom., 29.76 ; D. B., 25.0 ; W. B., 22.5 ; Humid., .69. 
" " Ip. m.-Barom., 29.78 ; D. B., 35.5; W.B., 33.0; Humid., .74. 
George Street Schoolhouse, Upper Room, March 24, 1887. 
TIME. 
8.50, . 
Scholars came in. Rear northwest window open one inch at top. Front 
northwest window one inch at bottom. Two rear southeast windows 
open one inch each at top. 
9.35, . 
Door into entry opened four inches to cool room. 
10.15, . 
Recess began. Northwest front window and southeast middle window 
opened to full size of lower sashes. 
10.33, . 
Northwest window closed. 
10.45, . 
Recess ended. Southeast middle window closed. Front northwest window 
left open three inches at bottom. 
11.17, . 
Air current in lower outlet tried with upper outlet closed. No continuous 
motion of air meter: discharge per hour estimated at 1,800 cubic feet. 
11.20, .. 
Upper outlet opened wide. Moderate flow of air outward; had not time to 
measure it. 
11.45, . 
School dismissed. 
11.50, . 
Air current in upper outlet tried. Slight downward draft, but fitful. 
Contents of room, 9,360 cubic feet. Air space for each of 56 scholars, 167 cubic feet. 
Average age of scholars, 7 years, 3 mouths. I 
GEORGE STREET SCHOOL HOUSE UPPER ROOM 
Observations March 24™ (887 
Carbonic tlciob ire re c/tir, parts erv JOOOO 
" " parts ire iOOOO 
JtelaOlve 7/ur/tixli-tp 
Temperature 
tri' school/ room/ 
fhrrnber of scholar's prescM/t 1888.] 
VENTILATION OF SCHOOL-ROOMS. 
357 
Other Observations: 
Baltimore Street Schoolhouse, Lower Room, Feb. 13, 1888. 
12.12 
co 
to 
11.10-20 
p 
10.30 
10.11-14 
10.00 
9.50, 
9.30 
9.00 
8.45-47 
CO 
g 
TIME. 
Number of per- 
1 
s 
s 
CO 
I 
co 
o 
-1 
1 
-4 
-4 
Ci 
M 
sons present. 
o 
-1 
Ci 
O' 
Air temperature 
1 
to 
to 
1 
GO 
1 
1 
1 
O 
o 
O' 
(Fahrenheit). 
Humidity of air 
co 
to 
to 
to 
to 
CO 
(percentage of 
1 
to 
00 
1 
(X 
CO 
I 
1 
O' 
1 
O' 
1 
1 
1 
complete satu- 
ration). 
Carbonic acid in 
1 
1 
1 
1 
1 
1 
-1 
w 
1 
1 
1 
| 
p 
GO 
| 
air (parts in 
co 
to 
h-* 
10,000). 
Hate of disch'ge 
S' 
13 
from outlets 
1 
1 
1 
1 
O' 
1 
1 
1 
1 
1 
O 
1 
1 
1 
1 
(cubic feet per 
o 
O 
hour). 
co 
to 
Temperature out 
p 
1 
1 
1 
1 
1 
1 
1 
1 
1 
1 
1 
1 
1 
Ci 
of doors. 
cn 
t 
Clear day. Wind from north, fresh. 
At Water Office, 8 a. m. -Barom., 30.13; D. B., 26.0; W. B., 24.5; Humid., .82. 
" " 1 p. M. - Barom., 30.14; D. B., 38.0; W. B., 35.0; Humid., .71. 
Baltimore Street Schoolhouse, Lower Room, Feb. 13, 1888. 
TIME. 
8.00, . 
School-room completely shut up; one cellar window out (replaced at once). 
Opened inlets and outlets. Quickened fires. 
8.15, . 
Opened top outlet (and left it open ten minutes). 
8.45, . 
Scholars came in. 
8.47, . 
Air sample taken in middle of room at breathing line. 
9.50, . 
Air-meter measurements at outlets: indicated discharge, 72,060 cubic feet 
per hour. 
10.11-14, . 
Air sample taken in middle of room at breathing line. 
10.27, . 
Recess began. Doors left open five or ten minutes. 
10.36, . 
Air sample taken in middle of room at breathing line. 
10.47, . 
Scholars came in from recess. 
11.10-20, . 
Air-meter measurements at outlets: indicated discharge, 65,520 cubic feet 
per hour. 
11.37, . 
Air sample taken in middle of room at breathing line. 
11.47, . 
School dismissed. 
Contents of room, 10,860 cubic feet. Air space for each of 59 scholars, 184 cubic feet. 
Average age of scholars, 6 years, 8 months. 358 
STATE BOARD OF HEALTH. 
[Jan. 
p 
JO 
• 
11.41-44, 
11.30 
11 05 
10.55, 
10.41-43, 
10.17-19, 
9.45 
9.30, 
8.45-47, 
00 
8% 
ft 
Number of per- 
I 
1 
o» 
O' 
h-4 
to 
o 
Ci 
Ci 
Cn 
O' 
to 
sons present. 
Ci 
Ci 
Ci 
Ci 
Ci 
Air temperature 
1 
CO 
I-* 
-4 
1 
& 
O' 
-I 
to 
co 
GO 
(Fahrenheit). 
Carbonic acid in 
1 
- I 
1 
1 
1 
** 
1 
| 
1 
I 
1 
O 
O' 
1 
air (parts in 
00 
Ci 
ot 
o 
10,000). 
Rate of disch'ge 
CO 
from outlets 
1 
1 
1 
1 
Ci 
to 
1 
1 
1 
1 
1 
1 
1 
1 
1 
(cubic feet per 
o 
hour). 
1 
i w 
<© 
to 
Temperature out 
C3 
1 
1 
1 
1 
1 
1 
1 
1 
1 
1 
1 
1 
Ci 
of doors. 
Baltimore Street Schoolhouse, Upper Room, Feb. 13, 1888. 
Clear day. Wind from north, fresh. 
At Water Office, 8 A.M. -Barom., 30.13; D. B., 26.0; W. B., 24.5; Humid., .82. 
" " 1 p.m. -Barom., 30.14; D. B., 38.0; W. B., 35.0; Humid., .71. 
T I M E . 
8.00, . 
Schoolhouse completely shut up. Opened inlets and outlets (including top 
outlet). Quickened tires. 
8.35, . 
Closed top outlet. 
8.45, . 
Scholars came in. 
8.50-52, 
Air sample taken in middle of upper room at breathing line. Opened top 
outlet. 
9.12, . 
Closed top outlet 
10.03, . 
Temperature upper room floor, 62.5°; five feet above floor, 66.5°. 
10.17-19, . 
Air sample taken in middle of room at breathing line. 
10.27, . 
Scholars went out at recess. Doors left open five or ten minutes. 
10.33, . 
Temperature of floor, 58°; five feet above floor, 74°. 
Air sample taken in middle of room at breathing line. 
10.41-43, . 
10.47, . 
Scholars came in from recess. 
10.55, . 
Air meter measurements at outlets : indicated discharge, 73,620 cubic feet per 
hour. 
11.05, . 
Temperature at floor, 65°; five feet above floor, 71°. 
Temperature at floor, 66°; five feet above floor, 69°. 
Air sample taken in middle of room at breathing line. 
11.30, . 
11 41-44, . 
11.50, . 
School dismissed. 
Baltimore Street Schoolhouse, Upper Room, Feb. 13, 1888. 
Contents of room, 10,740 cubic feet. Air space for each of 46 scholars, 233 cubic feet. 
Average age of scholars, 9 years, 3 months. 1888.] 
VENTILATION OF SCHOOL-ROOMS. 
359 
Baltimore Street Schoolhouse, Loiver Room, Feb. 18, 1888. 
to 
o 
c* 
to 
11.00,* 
10.40, 
10.30, 
10.00,* 
9.35-45 
9.30 
9.00, 
8.43-45 
8.40, 
8.00 
TIME. 
Number of per- ' 
i 
8 
8 
Ci 
o 
to 
to 
8 
8 
8 
8 
8 
8 
to 
1 
sons present. 
I 
8 
8 
© 
00 
Cl 
c: 
O' 
O' 
O 
O' 
00 
8 
65.5 
1 
Cl 
Cl 
o 
Cl 
Cl 
O' 
Cl 
O' 
1 
Air temperature 
(Fahrenheit). | 
Humidity of air | 
CO 
CO 
to 
to 
<•1*5 
co 
co 
to 
to 
(percentage of j 
i 
O' 
o 
OD 
O' 
1 
co 
1 
to 
Cl 
Cl 
1 
complete satu- i 
ration). 
Carbonic acid in 
I 
00 
O 
1 
1 
1 
O' 
Cl 
1 
CO 
© 
1 
1 
1 
1 
© 
Cl 
1 
1 
air (parts in 
1-* 
10,000). 
Kate of disch'ge 
from outlets 
I 
1 
4 
1 
1 
1 
1 
O' 
to 
1 
1 
1 
1 
1 
(cubic feet per 
hour). 
to 
Temperature out 
o 
O' 
1 
1 
1 
1 
1 
1 
1 
1 
1 
I 
1 
1 
1 
O' 
of doors. 
* Temperature on floor at main outlet, 63®. 
Clear-cloudy day. Wind from northwest, fresh. 
At Water Office, 8 a.M. - Barom., 29.97; D.B., 25.0; W. B., 24.0; Humid., .87. 
" " 1P.M. - Barom., 29.98; D. B., 35.0; W. B., 33.5; Humid., .84. 
Baltimore Street Schoolhouse, Lower Room, Feb. 18, 1888. 
TIME. 
7.50, . 
Schoolhouse completely shut up. Quickened fires. Opened all inlets and 
outlets (except top outlets), and opened three windows on each side about 
fifteen inches each (top and bottom). 
8.05, . 
Closed windows. 
8.43, . 
Scholars came in. 
8.45, . 
Air sample taken in middle of room at breathing line. 
9.35-45, 
Air-meter measurements at outlets: indicated discharge, 61,524 cubic feet 
per hour. 
10.15, . 
Air sample taken in middle of room at breathing line. 
10.22, . 
Recess began. Doors left open about ten minutes. 
10.40, . 
Air sample taken in middle of room at breathing line. 
10.45, . 
Scholars came in from recess. 
11.25, . 
Air-meter measurements at outlets (two openings only) : indicated discharge, 
slightly larger than before. 
11.42, . 
Air sample taken in middle of room at breathing line. 
11 50, . 
School dismissed. 
Contents of room, 10,860 cubic feet. Air space for each of 60 scholars, 181 cubic feet. 
Average age of scholars, 6 years, 8 months. 360 
STATE BOARD OF HEALTH. 
[Jan. 
Baltimore Street Schoolhouse, Upper Room, Feb. 18, 1888. 
H-4 
Q. 
H-* 
© 
11.20 
11.05-15, 
10.40,' 
10.30 
10.00 
8.47-50 
TIME. 
Number of per- 
1 
to 
to 
to 
to 
to 
to 
00 
© 
to 
to 
to 
to 
to 
1 
sons present. 
© 
I 63.5 
© 
© 
© 
© 
Air temperature 
1 
r-» 
to 
co 
1 
© 
co 
© 
© 
b« 
CD 
to 
© 
1 
(Fahrenheit). 
Carbonic acid in 
1 
1 
1 
1 
1 
1 
©1 
CD 
1 
© 
1 
1 
1 
© 
1 
air (parts in 
© 
to 
Qt 
10,000). 
cn 
Bate of disch'ge 
from outlets 
1 
1 
1 
1 
1 
oo 
1 
1 
1 
1 
1 
1 
1 
1 
1 
(cubic feet per 
hour). 
to 
Temperature out 
bi 
1 
1 
of doors. 
Clear-cloudy day. Wind from northwest, fresh. 
At Water Office, 8 A.M.- Barom., 29.97; D. B.,25.0; W. B., 24.0; Humid., .87. 
" " 1 p.m.- Barom., 29.98; D. B., 35.0; W. B., 33.5; Humid., .84. 
Baltimore Street Schoolhouse, Upper Room, Feb. 18, 1888. 
TIME. 
7.50, . 
School-room wholly shut up. Odor of coal-gas. Opened inlets and outlets 
(except top outlets). Quickened fires. Opened three windows on each 
side about fifteen inches each. 
8.05, . 
Closed windows. 
8.43, . 
Scholars came in. 
8.47-50, . 
Air sample taken in middle of room at breathing line. 
10.20, . 
Air sample taken in middle of room at breathing line. 
10.26, . 
Recess began. Doors left open about ten minutes. Fires quickened. Two 
to seven girls stayed in. 
10.42, . 
Air sample taken in middle of room at breathing line. 
10.48, . 
Scholars came in from recess. 
11.05-15, . 
Air-meter measurements at outlets: indicated discharge, 59,280 cubic feet 
per hour. 
11.33, . 
Air-meter measurements at outlets (two only): indicated discharge, about 
same as before. 
11.45, . 
Air sample taken in middle of room at breathing line. 
11.50, . 
School dismissed. 
Contents of room, 10,740 cubic feet. Air space for each of 42 scholars, 256 cubic feet. 
Average age of scholars, 9 years, 3 months. 1888.] 
VENTILATION OF SCHOOL-ROOMS. 
361 
Chase Avenue Schoolhouse, Upper Room, March 31, 1887. 
11.42-45, 
11.10-30 
11.00, 
10.44-48, 
10.10-15 
9.30, 
9.15, 
8.45-48 
TIME. 
CO 
co 
CO 
co 
co 
CO 
Number of per- 
© 
© 
© 
I-* 
to 
sous present. 
© 
© 
a> 
© 
ox 
Air temperature 
© 
O' 
Ox 
1 
to 
uo 
© 
(Fahrenheit). 
Humidity of air 
CO 
to 
(percentage of 
1 
1 
© 
1 
1 
© 
1 
1 
1 
complete satn» 
ration). 
Carbonic acid in 
© 
-I 
1 
1 
Ox 
to 
I 
1 
1 
to 
air (parts in 
to 
CO 
to 
10,000'. 
2? 
co 
Temperature out 
© 
1 
1 
4- 
1 
co 
1 
of doors. 
Clear day. Wind from north northwest, strong. 
At Water Office, 8 a.m.-Barom., 29.93; D. B., 25.5; W. B., 22.5; Humid., .56. 
" *• 1p.m. - Barom., 30.00; D.B.,39.0; W. B., 36.0; Humid., .73. 
Chase Avenue Schoolhouse, Upper Room, March 31, 1887. 
TIME. 
8.40, . 
Platform outlets all open, except one nearest to chimney. Upper outlets closed. 
Inlets all closed, on account of the cold I (Mercury at 544.) One fire burn- 
ing,- on northwest side. Quickened fire, and opened northwest inlet. 
8.50, . 
Scholars came in. 
9.00, . 
Went down cellar, and found chimney stove red-hot, and door into chimney 
wide open I Closed door. 
9.30, . 
Temperature, 72°. Opened southeast inlet. 
10.25, . 
Recess began. Scholars all went out. Teacher opsned two front windows 
on southeast side, from the bottom, about two feet each. 
10.35, . 
Windows closed. 
10.50, . 
Recess ended. 
11.05, . 
Teacher opened doors into entries. 
11.10, . 
One door closed, leaving the other open into a closed entry. 
11.47, . 
School dismissed. 
Contents of room, 10,170 cubic feet. Airspace for each of 36 scholars, 282 cubic feet. 
Average age of scholars, 10 years, 8 months.