The Use of Compressed and 
Rarefied Air, as a Substitute 
for Change of Climate, in 
the Treatment of Pul- 
monary Diseases. 
BY 
J. SOLIS €OHEN, M.D., Etc., 
PHILADELPHIA. 
REPRINTED FROM 
2Tf)e "Neto STodt jJUJetucal Jfournal 
for October 18, ISS.j. Reprinted from the New York Medical Journal for October 18, 188f 
THE USE OF 
COMPRESSED ARD RAREFIED AIR, AS A SUB- 
STITUTE FOR CHARGE OF CLIMATE, 
IN THE TREATMENT OF PULMONARY DISEASES * 
J. SOLIS-OOHEN, M. D., Etc. 
PHILADELPHIA. 
THE great desideratum in exiling poitrinaires is to secure to them 
an opportunity of being in the open air, so that their lungs 
shall have a proper respiratory diet. Such pabulum, taken naturally, 
is far superior to any artificial administration. But, for the benefit 
of individuals whose lack of money or whose domestic duties pre- 
clude their resort to a temperate climate, there is a substitute in 
periodic inhalations of air subjected to modifications of pressure. In 
many cases fully as much good can be secured by this treatment as 
by change of climate, and in a few much more; though, in the vast 
majority of cases in which change of climate is advisable, it is but 
a poor substitute. Its efficacy, however, has never been appreciated 
in the United States, although fully recognized in Europe, especially 
on the continent. 
For some twenty years I have made occasional resort to this 
method of treatment as suitable cases presented; but special lines 
of practice have gg closely occupied time and thoughts that the 
method has never been pushed for the purpose of attracting patients, 
while little has been contributed by me to the literature of the sub- 
ject, save that written in the two editions of my “ Treatise on 
Inhalation” (Philadelphia, 1867 and 1876). 
The time required for the proper administration of an inhalation 
of compressed or rarefied air—from twenty to thirty minutes—is 
too great for a busy practitioner to bestow daily, or twice a day, 
* Read before the American Climatological Association, May 5, 1884, 2 
COMPRESSED AND RAREFIED AIR IN PULMONARY DISEASES. 
upon individual patients; and it is only by massing patients, and 
having them inhale simultaneously from a number of apparatus, that 
this department of practice can be rendered sufficiently remunera- 
tive to attract careful supervision. Hence it is mainly confined to 
institutions fitted up for the purpose, and has not become incor- 
porated into private practice. Patients whose means permit them 
to purchase apparatus for their own use can bo instructed how to 
take their inhalations at home; and the method of treatment will 
begin to receive the professional attention it merits whenever ap- 
paratus of moderate cost can be supplied for this purpose. Hither- 
to the apparatus constructed with this view have been too costly 
and too cumbersome. An approach to a suitable contrivance for in- 
haling compressed air has been made in my own office by the com- 
bined efforts of my brother, Dr. Solomon Solis-Cohen, and Mr. 
Charles Richardson, physicist in Queen & Co.’s establishment, Phila- 
delphia. 
This apparatus, like that of Waldenburg and some others, utilizes 
the gasometer principle—a principle which years of experimentation 
with different methods have convinced me is the best adapted to the 
purpose. By weighting the inner cylinder (air-chamber) at the bot- 
tom, accurately adjusting its diameter to that of the outer one (water- 
chamber), and pumping the air into it by means of a foot-bellows, 
the cumbersome arrangement of ropes and pulleys is done away with, 
and the size of the machine considerably reduced. One of these 
instruments (Fig. 1), which has been in office use more than six 
months, consists of an inner hollow cylinder 12 inches in diameter 
and 20 inches * high, open at the bottom, but having two shelves, 
as it were, upon which to rest the weights—as if the cylinder had 
been covered in, top and bottom, and a longitudinal strip cut out 
of the middle of the base. The outer cylinder, open at the top, is 
just enough larger than the inner cylinder to enable the latter to slide 
up and down in it without grooves or flanges upon either. A rim 
upon the inner cylinder prevents it from sinking quite to the bot- 
tom of the water-chamber—a preservative device. A tank to catch 
the water displaced by pressure is placed around the outer cylinder, 
reaching about half way down, and communicating with the cylin- 
der by means of a row of holes bored in the cylinder at the level 
of the base of the tank. The diameter of the upper rim of the tank 
is 16 inches. A line painted on the outer cylinder indicates the 
* A machine 18 inches high can be used ; one 24 inches high will give better 
mechanical results. COMPRESSED AND RAREFIED AIR IN PULMONARY DISEASES. 
water level, and a line painted on the inner cylinder indicates how 
high it may he pumped without being thrown out of the water. 
Both of these points, while susceptible of calculation, are conveni- 
ently ascertained by experiment with the highest pressure intended 
to be used. 
The weights are of lead, segments of circles in shape, so as to 
assist in maintaining the equilibrium of the inner cylinder. A very 
simple calculation will give the proper weight for every fraction of 
an atmosphere intended to be used.* Thus, with an air-chamber of 
12 inches diameter, upon which there is an atmospheric pressure of 
about 1,696'50 pounds, we should need, in round numbers: 
For yV °f an atmosphere, 24£ pounds. 
For -g “ “ 28|- “ 
For “ “ 34 
For “ “ “ 
The inner cylinder weighs a little over four pounds. Placing 
on its shelves twenty pounds, we augment the pressure by TU- of an 
atmosphere, and the additional weights are placed atop of it as re- 
quired. A gauge may be attached at a slight additional expense ; 
but it is unnecessary, as the pressure is verified by the manufacturer 
before delivery of the apparatus. Of course, the top of the inner 
cylinder is pierced with two holes, into which are fitted two goose- 
necks—one for the attachment of the tube from the bellows, the 
other for the attachment of the tube to the stop-cock and mouth- 
piece—Waldenburg’s being at present employed in the absence of 
a better form. The water may be run in through either of these 
pipes, and drawn off by means of a stop-cock at the bottom of the 
outer cylinder. When it is desired to cleanse the apparatus, the 
inner cylinder may easily be lifted out. The expense of the gasome- 
ter, weights, bellows, and tubing is in the neighborhood of twenty 
dollars; but the manufacturers think that, if sufficient demand exists 
to warrant making the apparatus in quantity, this figure can be 
reduced to fifteen dollars. The accompanying diagrams will render 
the description of the apparatus clearer. 
The immediate effect of inhaling compressed air is to dilate the 
lungs and thorax to a greater extent than can be accomplished by 
the deepest possible voluntary inspiration at the ordinary pressure. 
The inspiratory portion of the respiratory act is thus greatly facili- 
tated. To avoid rupture of the air-cells, it is not safe, especially with 
* This has been ascertained by experiment to be the best size.  COMPRESSED AND RAREFIED AIR IN' PULMONARY DISEASES. 
4 
invalids, to employ a greater pressure than from to additional 
atmospheric pressure at first, gradually increased to or -g1 The 
jU additional pressure need never be exceeded. This method of 
Pig. I.—Cohen and Richardson’s Compressed Air Apparatus, 
Pig. 2.—Section showing the method of weighting the inner cylinder. At the level of the 
arrow, A, a row of holes is bored through the outer cylinder to permit the escape of 
water. 
treatment is indicated in early phthisis, in chronic bronchitis, in the 
partial collapse of lung sometimes following pneumonias, and, in fact, COMPRESSED AND RAREFIED AIR IN PULMONARY DISEASES. 
5 
in all cases in which it is desirable to augment the vital capacity of 
the lungs, except in those instances where there exists a strong dis- 
position to haemorrhage. As the increased pressure on the intratho- 
racic organs increases the general intravascular pressure, it is easy to 
understand that such treatment is imprudent in individuals disposed 
to hemoptysis, hseraatemesis, epistaxis, hemorrhoids, or other blood- 
loss. 
The immediate eifect of expiration into compressed air is to im- 
pede that portion of the respiratory act. This will tend to dilate 
the air-cells and rectify collapsed lung by backward pressure, so to 
speak, thus accomplishing the same results as inspiration of com- 
pressed air. The only advantage gained is in the muscular effort 
necessary to breathe into compressed air, and this can be well utilized 
in cases in which it may be an object of importance to increase the 
power of the respiratory muscles by systematic gymnastic exercise. 
For weak patients the method is unsuitable. Tendency to haemor- 
rhage is a contra-indication for the process. 
The immediate effect of inspirations of rarefied air is by diffusion 
to tend to diminish the pressure of the air in the lungs. The greater 
pressure of the atmosphere externally is demonstrated by recession of 
the intercostal parietes, and of the soft parts above and below the 
sternum. The method thus acts as a gymnastic exercise for the mus- 
cles of respiration. The special therapeutic effect approaches that 
produced by residence at high latitudes, for which in certain cases 
it may prove an acceptable substitute. 
The immediate effect of expirations into rarefied air is to ex- 
haust a portion of the residual air in the lungs and thus favor the 
collapse of the distended air-cells. The indication for the practice 
of the method is found in asthma and in pulmonary emphysema. 
And here I believe the home treatment by apparatus is often more 
efficacious than change of climate. 
Had the pressure of other duties permitted, these remarks would, 
have been extended, and the value of the various plans of treatment 
would have been illustrated by the records of typical cases. Even 
in the study of pulmonary diseases alone, we need to consider the 
effects, both immediate and mediate, upon the heart and circulatory 
system in general, produced by the use of these methods. The sys- 
temic effects, too, such as increased appetite and improved digestive 
powers, in some cases of phthisis, deserve a modicum of attention. 
But the writer’s object has been accomplished in simply recalling 
attention to a neglected therapeutic art, in the hope that some of  COMPRESSED AND RAREFIED AIR IN PULMONARY DISEASES. 
6 
those present, or some of those who may read the report of the 
papers presented at this meeting, may he incited to study the sub- 
ject more thoroughly. 
It may be added, in conclusion, that auscultation and percussion 
during respiration of air subjected to compression or rarefaction 
bring out in relief special phenomena obscure or doubtful under the 
ordinary methods of auscultation and percussion, while some sounds 
are evolved which otherwise escape detection altogether. The lew York Medical Journal, 
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