[From the Sixth Annual Report of the Mass. State Board of Health. ] 
Ventilation of Railroad Cars, 
By THEO. W. FISHER, M.D. 
Of Boston. 
WITH CHEMICAL ANALYSES, 
By WM. RIPLEY NICHOLS, 
PROFESSOR OF GENERAL CHEMISTRY IN THE MASSACHUSETTS INSTITUTE OF TECHNOLOGY. 
BOSTON: 
WRIGHT & POTTER, STATE PRINTERS, 
79 Milk Strret (corner of Federal). 
I^7S- VENTILATION OF RAILROAD CARS. 
By THEO. W.IfISHER, M. D. 
(Of Boston.) 
WITH CHEMICAL ANALYSES, 
By WM. RIPLklf NICHOLS, 
Professor of General Chemistry in the Massachusetts Institute 
of Technology. VENTILATION OE RAILROAD CARS. 
The object of this paper is briefly to call public attention 
to the insanitary condition of the passenger-cars on our rail- 
roads, and to introduce some tests and experiments on the 
air in smoking and other cars made by Prof. W. R. Nichols, 
of the Massachusetts Institute of Technology, at the request 
of the State Board of Health. 
This subject of car-ventilation may seem trivial when we 
consider the brief period of occupancy in individual cases, 
but even in this point of view, it is of some importance; and 
to that quite large class of persons who spend several hours 
daily in the cars, it is of the most vital interest. The Ameri- 
can people are eminently a travelling public, and the aggre- 
gate of time spent in this way is worth considering. Massa- 
chusetts, according to the Railroad Commissioners’ Report for 
1873, has 1,735 miles of railroad, or about one mile to every 
879 inhabitants, and to every four square miles of territory. 
The number of passengers carried annually is over forty-two 
millions. These facts show the importance of making all public 
conveyances equal, at least, in their hygienic condition, to our 
School-houses and other public buildings.. 
That this is not the case, the travelling public has daily 
sensible demonstration. Universally defective methods of 
heating and ventilation of steam-cars lead to bad air, op- 
pressed breathing, hot, heavy and aching heads, cold feet, 
coughs and debility, to say nothing of the discomforts of heat, 
dust and bad odors in summer. To these are added the 
deleterious effects of the concentrated fames of tobacco, when 
the traveller is driven for a seat to the smoking-car. 
A striking illustration of how bad the condition of things 
O O STATE BOARD OF HEALTH. 
228 
[Jail. 
may become, is found in a monograph, by the Baron N. de 
Derschau, a Russian engineer, upon Heating and Ventilation 
of Railway Cars (Paris, 1871). An experiment was made 
on an American car, running as third-class between St. 
Petersburg and Moscow, during the winter of 1866. The 
car was 50 feet long, and carried 80 passengers. The outside 
temperature at starting was 22° F. below zero, the inside 16° 
below, and there was no means of heating. Observations 
were made hourly, with the following result: The temperature 
rose from the accumulation of animal heat until, at the end of 
nine hours, it was, in the upper part of the car, 21° above 
zero, while on the floor it was still 6° below. The carbonic 
acid increased to alarming proportions; viz., from .140 per 
cent, at starting to .940 per cent, the last hour! The hy- 
grometer, as well as the frost on the windows and the fog in 
the air, showed that the saturation point for moisture had 
been reached. The experimenter left the car at the ninth 
hour physically unable to continue his tests. 
This was, of course, an extreme example of what exists in 
a less degree in every ill-ventilated car. In cold and rainy, 
or in hot and dusty weather, the opening of windows is im- 
practicable, and passengers suffer the insidious effects of bad 
air in avoiding the more obvious dangers from dust aud 
draughts. The opening of doors at stations affords but little 
relief, since the cars are not then in motion so as to create a 
thorough draught. 
The smoking-car is a purely American institution. In 
England and France, smoking is forbidden in the first and 
second class carriages, but is connived at by the guards, on 
the payment of a small fee, if no one in the compartment 
objects. In Germany, smoking is so universal that a con-* 
trary custom prevails, and smoking is allowed everywhere, 
except in certain compartments marked " Fur nicht Raucher” 
(no smoking), where tourists and ladies may avoid the fumes 
of pipe and cigar, if they wish. Our custom is to collect all 
smokers into one car, thus concentrating the products of 
burning tobacco, which might otherwise be diffused through 
the whole train. 
The bad hygienic condition of these moving fumatories 
must be more or less familiar to all. The fact that the air is 1875.] 
VENTILATION OF CARS. 
229 
irrespirable by most non-smokers, including the whole female 
sex, is sufficient to show this without the aid of chemical tests, 
which often fail to detect subtle atmospheric qualities, which 
may be evident to the senses, and fruitful sources of disease 
and death. Exceptional mischief of a serious kind has 
recently served to direct attention to the above fact; a young 
man having been killed by falling from the platform of a 
moving train, in consequence, it was supposed, of the dizzi- 
ness produced by a brief stay in the smoking-car. 
The following experiments of Prof. Nichols will furnish 
approximate evidence of the purity of the air in cars, under 
various circumstances, by showing the amount of carbonic 
acid present. This gas is irrespirable, except in the smallest 
quantities, and is generally accepted as a fair standard of the 
amount of other impurities given off by the skin and lungs, 
which tend by their immediate putrefaction to produce directly 
poisonous effects upon the human system. 
Massachusetts Institute of Technology, 
Boston, December 12, 1874. 
Dear Sir :—Having been requested by Dr. Folsom, Sec- 
retary of the State Board of Health, to make some investiga- 
tions into the character of the air in smoking-cars, I beg 
leave to report herewith the results of such determinations 
as have been made. 
Every one recognizes the " closeness ” of the air on enter- 
ing, at this season of the year, an ordinary passenger-car 
which is moderately full. We are not able to determine 
exactly the substances in the air which cause this feeling and 
which produce the injurious effects experienced by remaining 
for a considerable length of time in ill-ventilated or over- 
crowded apartments. As, however, the exhalations and 
emanations causing the injurious effects are always composed 
in part of, or attended by, carbonic acid, and as the amount 
of this compound can be estimated with great exactness, it 
is usual to take the carbonic acid as affording an indication of 
the completeness or deficiency of the ventilation. 
In the case of smoking-cars, in addition to the exhalations 
and emanations from the passengers, the products of the 
tobacco consumed mix with the air and render it oppressive 230 
STATE BOARD OF HEALTH. 
[Jan. 
to most non-smokers. The products of the combustion of 
tobacco, if the combustion were complete, would be carbonic 
acid, ammonia and water; in the process of smoking, how- 
ever, most of the tobacco is distilled rather than burned, and 
the products of this distillation are quite numerous and com- 
plex. The most complete investigation into the composition 
of tobacco-smoke with which I am acquainted, was made by 
Voki and Eulenburg.* They smoked artificially a consider- 
able quantity of tobacco and claim to have recognized with 
distinctness in the smoke, cyanhydric acid, sulphuretted 
hydrogen; certain acids of the fatty acid series,—namely, 
formic, acetic, propionic, butyric and valerianic; also, car- 
bolic acid and creasote; also, pyridin, picolin, collidin and 
other similar alkaloids, but no nicotin. They found also, in 
the smoke, ammonia, nitrogen and oxygen, and small quan- 
tities of marsh-gas and carbonic oxide. 
I have made several attempts to obtain evidence, by chem- 
ical means, of the presence in the air of smoking-cars of some 
of the characteristic products of the smoking of tobacco, but 
without success, On one occasion I rode from Worcester to 
Boston, drawing a portion of the air of the car through 
proper absorbing media. The train was express, and the car 
was completely filled, and the smokers were about in the 
usual proportion,—perhaps one-half of the passengers were 
smoking. Of the peculiar components of the tobacco-smoke, 
it seemed to me that the fatty acids, so called, butyric, vale- 
rianic and acetic acids, would be bodies to be tested for with 
the greatest hope of success, but I tested also for the alkaloid 
bodies, which probably form the most injurious portions of 
the smoke. On this occasion 10 liters gallons) of air 
were drawn through the absorbing liquid, but the results 
were negative. On another occasion 30 liters of air were 
employed, and on several other occasions quantities lying 
between these two; in no case was I successful in separating 
and identifying any of these peculiar products. This, how- 
ever, is not a matter of great surprise. Vohl and Eulenburg, 
in the experiments mentioned above, appear to have deter- 
mined the character of the acid products by consuming 50 
cigars, and the alkaline products by the consumption of 100 
* Archiv der Pharmacie, [2] 147 (1871,) p. 130. 1875.] 
VENTILATION OF CARS. 
231 
more. The statement is not, however, quite clear,* and the 
amount of any substance obtained is not given. The whole 
of the products of the distillation (except the permanent 
gases) were condensed by them or absorbed in appropriate 
liquids ; in the actual process of smoking, a considerable 
quantity of these substances are absorbed by the smoker, and 
what does escape into the air is so diffused, even in a poorly 
ventilated car, that it would be necessary to use a very large 
amount of air in order to discover the peculiar bodies of 
tobacco-smoke, and even then the amount, except by the use 
of cars-full of air, would be too small to estimate quantita- 
tively. A very little tobacco-smoko does indeed affect the 
eyes and throat of a person unaccustomed to its use, but our 
senses are often affected by quantities too small to weigh, too 
small even to detect by chemical means. 
The question, then, from a chemical point of view, seemed 
to resolve itself into a question of ventilation, and a number 
of experiments were made to determine the amount of car- 
bonic acid in the air of the cars. The results of these experi- 
ments are embodied in the following table. 
The following experiments were made to see whether there 
was an increase of carbonic acid during the trip :— 
* The process of separating the alkaloids required several fractional distillations 
and recrystallizations of the platinum compounds into which they were converted. 
The authors detail the separation, the identification by physical properties, the deter- 
mination of the boiling-point, the elementary analysis, and the analysis of the plati- 
num compounds in each case. It seems hardly possible that so small an amount of 
tobacco as indicated above, could have furnished the material for reliable determina- 
tions, and it is possible that some error may have crept into the statement of the 
amount. 232 
STATE BOARD OF HEALTH. 
[Jan. 
No. 
Date. 
Carbonic Acid 
in volumes, 
per cent. 
RAILROAD. 
Description of Train. 
Sample taken between— 
1 
Nov. 4, . 
0.233 
Providence, . 
Dedham train reaching Boston at 7.35 A. m>, . . . 
Roxbury and Boston. 
2 
4, . 
0.261 
it 
« 
3 
4, . 
0.173 
“ 
Same train as Nos. 1 and 2 ; different car, not so full, . 
CC CC 
4 
7, • 
0.335 ' 
CC 
Dedham train reaching Boston at 7.18 A. M.,. 
cc cc 
5 
13, . 
0.283 
cc 
1 
cc cc 
6 
23, . 
0.253 
It 
}> Stoughton train reaching Boston at 8.10 A. M., . . < 
cc cc 
7 
24, . 
0 171 
cc 
J l 
cc cc 
8 
27, . 
0.242 
Fitchburg, . 
\ Watertown Branch train leaving Boston at 5.55 p. m., . <: 
Boston and Cambridge. 
9 
27, . 
0.140 
CC 
Cambridge and Mt. Auburn. 
10 
Dec. 3, . 
0.369 
Providence, . 
' Dedham train, due in Boston at 7.35 A. M., . 
Boylston and Boston. 
11 
3,’. 
0.317 
CC 
Stoughton train, due in Boston at 8.10 A. M.,. 
CC CC 
12 
4, . 
0.098 
Eastern, 
Train leaving Boston at 5 P. M., 
Boston and Lynn. 
13 
4, . 
0.127 
CC 
Train reaching Boston at 6.25 p. m., 
Lynn and Boston. 
14 
9, . 
0.234 
Fitchburg, . 
Same train as Nos. 8 and 9, 
Boston and Cambridge. 
15 
9, . 
0.179 
CC 
Cambridge and Mt. Auburn. 
Note.—The method employed for estimating the carbonic acid, was that known as Pettenkofer’s, and thd air was taken at the height of the heads of 
the seated passengers. 
Table No. 1.—Smoking-Cars. 1875.] 
VENTILATION OF CARS. 
233 
No. 
Date. 
Carbonic Acid 
in volumes, 
per cent. 
KAILKOAD. 
Description of Train. 
Samples taken between— 
16 
17 
Nov. 13, 
24, 
0.367 
0.298 
Providence, . 
tt 
Stoughton train reaching Boston at 8.10 A. M., . . 
Jamaica Plain and Boston. 
tt tt tt 
18 
Dec. 3, 
0.174 
tt 
Dedham train reaching Boston at 7.18 A. M.,. 
Boylston and Boston. 
19 
3, 
0.174 
tt 
Stoughton train reaching Boston at 8.10 A. M., 
tt tt 
20 
8, 
0.159 
It 
train reaching Boston at 7.35 a. sr., samples^ 
21 
• 
8, 
0.219 
tt 
/ taken in different cars, / 
Note.—The trains mentioned in Tables No. 1 and No. 2, were all local, and the greatest distance passed over, before the sample 
was taken, was about fourteen miles. 
The following determinations were made in ordinary passenger-cars :— 
Table No. 2.—Passenger-Cars. STATE BOARD OF HEALTH. 
[Jan. 
The air in the smoking-car of the Stonington steamboat 
train, on the Boston and Providence Railroad, was examined 
at intervals during the journey from Boston to Providence, 
Friday, December 11, 1874. The train left Boston at 5.30 
p.m., reaching Providence at 7.05 r.M. The capacity of the 
car was about 2,750 cubic feet net. The number of passen- 
gers was thirty-seven, of whom eighteen were smoking. 
This was about the average during the trip. 
No. 
Carbonic Acid 
. volume, 
per cent. 
TIME. 
Xength of Time. 
After leaving— 
/ 
1 
0.172 
5.35 P. M., . 
5 minutes, 
Boston. 
2 
0.158 
5.50 . 
20 
Boston. 
3 
0.153 
6.05 “ . 
35 
Boston. 
- 
6.10 “ . 
* 
- 
4 
0.194 
6.15 “ . 
5 “ . 
Sharon. 
- 
6.22 “ . 
t 
- 
5 
0.165 
6.35 “ . 
12 
Mansfield. 
- 
6.38 “ . 
t 
- 
6 
0.177 
6.45 “ 
7 
Attleborough. 
* 
Train stopped at Sharon. f Train stopped at Mansfield. 
$ Train stopped at Attleborough. 
A somewhat similar experiment (but less extended) was 
made December 9, 1874, on the Watertown branch of the 
Fitchburg Railroad. The capacity of .the car (after deducting 
the space actually occupied by the passengers) was about 
2,350 cubic feet. 
No. 
Carbonic Acid 
volume, 
per cent. 
Number 
of 
Passengers. 
Number 
Smoking. 
Time. 
Train— 
_ 
_ 
5.55 P. M. 
Left Boston. 
- 
- 
- 
5.58 “ 
Left Charlestown. • 
1 
0.234 
44 
15 
6.05 “ 
- 
- 
- 
- 
6.07 “ 
Stopped at Cambridge. 
2 
0.i79 
34 
8 
6.10 “ 
- 
- 
• 
- 
6.13 “ 
Stopped at Mt. Auburn. 1875.] 
VENTILATION OF CARS. 
235 
On several occasions, I made comparative tests for the 
ammonia present in smoking-cars and passenger-cars. The 
amounts in the following table are comparative, simply. 
1. Outer air, Back Bay, average, 100 
2. Nov. 13. Providence Railroad smoking-car, .... 575 
3. Dec. 4. Eastern Railroad smoking-car, 310 
4. “ 4. “ “ “ “ after stopping at a 
station, . . . . . . . . . 266 
5. “ 11. Providence Railroad steamboat train, taken at same 
time as carbonic acid (No. 3) of same date, . 400 
6. “ 11. Ditto. Taken at same time as carbonic acid (No. 6) 
of same date, 340 
7. “ 8. Providence Railroad, common car, .... 135 
8. “ 8. “ “ another “ . . 175 
I may remark, that more of the samples have been taken 
on the Providence Railroad than on any other, simply be- 
cause it was more convenient of access. 
Yours very respectfully, 
Dr. T. W. Fisher. 
Wm. Ripley Nichols. 
The first fact noticeable in Prof. Nichols’ report is, that the 
amount of carbonic acid found in cars exceeds considerably 
the average for public buildings, and is, of course, largely in 
excess of what would be found in the dwellings of the better 
classes, or in the open air. In the Report of the State Board 
of Health, for 1871, an article, by the late Dr. Derby, on 
"Air, and some of its Impurities,” gives the average per cent, 
for the outer air in this vicinity as .035, and for school-houses 
as about .140. The Music Hall is set down at .140 after a 
concert; Municipal Court-room, .120; Globe Theatre, .144; 
Waiting-room of Public Library, from .136 to .193, etc. 
The average of Table No. 1 gives the percentage for smok- 
ing-cars at .228, the lowest example being .127, and the high- 
est .369. The average of Table No. 2 gives for passenger- 
cars a percentage of .232 ; lowest, .174 ; highest, .367. The 
air on the Stonington steamboat-train smoking-car was ex- 
ceptionally pure, the average being .170. The car was by 
no means full, and but half were smoking. The smoking- STATE BOARD OF HEALTH. 
[Jan. 
cars of the New York express trains, on the Boston & Albany 
Railroad, would, perhaps, furnish more marked results. These 
cars will accommodate 70 passengers, and, according to Mr. F. 
D. Adams, of that road, are usually filled with smokers, who 
play euchre from Boston to New York, in an atmosphere of 
dense smoke. The ordinary ventilators are of no use in 
clearing the car, and wickets in the ends are required to 
make any impression on it. 
The tables show also a second fact; viz., that the addi- 
tional amount of carbonic acid produced by the combustion 
of a few ounces of tobacco is hardly appreciable. Prof. 
Nichols estimates that if all the carbon of the tobacco were 
completely burned to carbonic acid, the carbonic acid formed 
might amount in weight, at a maximum, to one-quarter more 
than the amount of tobacco consumed. In actual practice, 
however, much of the carbon is not burned to carbonic acid, 
but some is given off in the state of carbonic oxide, and more, 
probably, in the form of compounds of carbon and hydro- 
gen in matters of the nature of tar. The carbonic acid 
from this source would not indicate, however, any additional 
impurities from the lungs and skin, and it may be disregarded. 
A newspaper paragraph is authority for the statement, that 
Dr. Otto Krause, of Annaberg, Saxony, has found nine per 
cent, of carbonic oxide in tobacco-smoke; but this seems a 
large amount. 
Let us examine, then, this question of ventilation in 
another way. The average capacity of a passenger-car 
is about 2,500 cubic feet of net air-space, excluding that 
occupied by passengers and furniture. A smoking-car, as 
arranged with tables, chairs and sofas will accommodate 
at least 50, and an ordinary car 75 passengers. This gives, 
in the first case 50, and in the last cubic feet of air- 
space to each passenger. The amount of air-space and of 
air per hour to insure proper ventilation has been variously 
estimated. Army regulations for hospitals and barracks 
require from 1,000 to 1,500 cubic feet of air, changed hourly, 
per soldier. The British Royal Commissioners, appointed in 
1857, recommend GOO cubic feet of air-space, and 20 feet of 
air per minute and per man. Ten feet per minute is the 
lowest estimate suggested in any case. Take 15 feet per 1875.] 
VENTILATION OF CARS. 
237 
minute, then, as ail average, and the air in smoking-cars 
should be changed thoroughly at least every four minutes, 
and in ordinary cars every three minutes, to insure proper 
ventilation. It is evident this is never accomplished. 
It may be useful to insert here a table from a standard 
French work, by Gen. Morin, on "Heating and Ventilation” 
(Paris, 1874). I have reduced the metres to feet for con- 
venience’ sake. 
Volume of air necessary to introduce and withdraw hourly for each 
person, to insure good ventilation. 
•Cubic feet. 
Hospitals, 
'Ordinary sickness, 2,100-2,450 
Surgical and lying-in, .... 3,500 
Epidemic, 5,250 
Prisons, . . . • 1,750 
Workshops, . 
' Ordinary, 
Unhealthy, 
2,100 
3,500 
1,050 
1,750 
Barracks, 
Theatres, 
Public halls, . 
Lecture rooms, 
By day, 
By night, 
. • . . . . 1,400 
2,100 
1,050 
Schools,. 
Infant,. 
Adult, . 
• 420-525 
875-1,050 
Stables, . 
6,300 
These figures, Gen. Morin states, are based on direct 
observation, and are not in the least exaggerated. The 
point at which all sensible odor from effete animal matter 
disappears is taken as the limit of satisfactory ventilation. 
This limit is not usually reached while more than .06 per 
cent, of carbonic acid remains. 
Dr. R. Angus Smith says, in his "Air and Rain,” a work 
of .undoubted authority: "We cannot accept a lower stand- 
ard of carbonic acid than .06 per cent.; and uniform diffu- 
sion being supposed, we cannot preserve our minimum 
standard of purity with a less delivery of fresh air than 
3,000 cubic feet per head per hour!” This limit is also 
recommended by Pettenkofer. It will be seen how wide 
of any such standard is the condition of our steam-cars when 
each passenger has only from to 50 feet of air-space; 
and air so seldom changed as to leave a percentage of from 
0.2 to 0.3 volumes of carbonic acid ! 
The heating and ventilation of cars seem to be inseparable 
subjects. The monogram of the Baron de Dershau treats STATE BOARD OF HEALTH. 
[Jan. 
of the former in quite a thorough manner. He mentions 
only to condemn the various methods in use, such as foot- 
warmers of hot water or hot tiles, hot-water pipes, stoves of 
porcelain and iron, and iron stoves outside the cars, over 
which air is conducted to the interior. He concludes that 
steam alone is adapted to the purpose; and it is impossible 
not to agree with him, when we think of the dangerous and 
unmanageable fire-boxes so universally in use with us. Oui 
stoves, besides overheating the air when approaching a red- 
heat, as is often the case, are subject to as great extremes of 
temperature as a bad case of chills and fever. The heat is 
also badly diffused in the car, and is of little or no aid to 
ventilation. 
Steam-heating is in use on some American railroads, as 
well as in Russia, Belgium, Germany and Austria. The 
Baron de Dershau gives a complete description, with plans 
and specifications, of a system which he has introduced with 
success in Russia and elsewhere. It consists, briefly, of a 
special boiler for every eight cars, placed in a small compart- 
ment at the end of one of them, and tended from the plat- 
form. The steam is conveyed along the roofs in pipes 
encased in felt, and fed by vertical pipes into heating-tubes 
along the sides of the car-floor, the water of condensation 
being returned to the boiler by a pipe beneath the cars. 
This system seems to have had no special relation to the venti- 
lation of the compartments to which it was applied. This was 
provided for by an opening in the roof, allowing for a tem- 
perate climate 22 and for a cold climate 28 square centi- 
meters of area for each passenger. Air was admitted by 
ventilators under the eaves, with openings arranged to catch 
the draught of the moving train. In a car fitted up for the 
emperor’s summer use, air was admitted through wire screens 
in the floor, and carried up through hollow pillars contain- 
ing a cooling mixture, being discharged through small orna- 
mental openings in the capitals into the cai. 
Most American cars are now made with the Wagner 
monitor-roof, with patent pipes and apertures for the exit of 
foul and heated air, in great number and variety. These are 
not efficient, however, without provision for the admission of 
fresh supplies of air from below. Side and end ventilators 1875.] 
VENTILATION OF CARS. 
239 
have therefore been devised for this purpose, but are all open 
to certain objections. Those in the letter-line over the 
windows are too high up, and, as well as the wicket-sashes in 
the doors and end-windows, expose passengers to severe 
draughts, and, consequently, are seldom allowed to be open. 
The eighth annual report of the Master Car-builders’ As- 
sociation, in convention at Cincinnati in June of last year, 
contains the report of a committee on heating and ventilation 
of much interest. The discussion on this report clearly shows 
the difficulties of the subject, and the various opinions and 
experiences of the representatives of different railroads, as 
well as a disposition to do something to improve the con- 
struction of cars, with respect to their sanitary arrangements. 
The report admits fully the importance of veutilation, and 
quotes at length Dr. Smith’s experiments upon himself in the 
lead-chamber. It admits that a car has hardly sufficient air- 
space for four, instead of seventy-five persons; and that the 
solid and liquid impurities given off by a car-full of passen- 
gers, amounting, according to Prof. Huxley’s estimate, to two 
pounds every twenty minutes, will no more go out of roof- 
ventilators without forcing,, than fire-damp out of a mine. 
The top and letter-line ventilators have proved entirely 
inadequate to effect the requisite change of air. The arrange- 
ments for admitting air at the end of the car, depending on 
the motion of the train, arc most efficient, but most objection- 
able on account of the draught. To admit 2,400 feet per 
minute, at as slow a rate as five feet per second, there must be 
an opening as large as the whole end of the car; to make a 
greater velocity endurable, the air must be distributed 
through the car before reaching the passengers. 
The system of Messrs. Sanborn & Gates, 15 West Street, 
Boston, was mentioned very favorably by the committee. This 
consists in a fan-wheel, carried by a pulley attached to one of 
the axles, which forces air into the car, through a strainer of 
wire-gauze, at the first side window. The air is conducted 
around the roof in a 6-iuch pipe, perforated at proper inter- 
vals, and finds its exit through registers in the floor. This 
apparatus has been applied to a car on the Boston & Albany 
Railroad, and was tested by a company of gentlemen well 
known to the public, in May last. The report of a committee STATE BOARD OF HEALTH. 
[Jan. ’75. 
of observation will be found in the "Boston Post, May 6, 
1874. When the car had been thoroughly filled with smoke, 
on admitting the air it was entirely cleared in about six 
minutes. It is intended to regulate the temperature and 
moisture by means of a heater and evaporator. 
Mr. Adams, of the Boston & Albany Railroad, says the 
above apparatus works well, except on up-grades, where 
speed is too low for the best effect. It seems evident that 
some combination of steam-heating and forced ventilation 
must some time be found to solve the problem under consider- 
ation, unless railroad companies continue to be deterred by 
the expense incidental to its introduction. It was not in- 
tended to go into a critical examination of methods here. 
Such practical questions are for car-builders and railroad 
corporations to consider. The public should see that the 
efforts of these parties are not suspended through motives of 
false economy, or a lack of appreciation of the importance of 
perfect ventilation for all passenger-cars, both summer and 
winter, and in all weathers.