JULY 30, 1897.] 
lowlands. Although the surface of the 
earth receives more heat at high elevations, 
it is immediately reflected back into space 
without heating the air to a corresponding 
degree. ‘This is evidenced by the fact that 
at high altitudes the difference of the tem- 
perature in the sun and in the shade is 
greater than in the lowlands. But the effect 
of the sun’s rays is felt more keenly at a 
high elevation, so much so that persons 
staying at Davos can enjoy a sun-bath in a 
sheltered spot even in the cold of winter, 
although wearing much thinner clothing 
than at home. 
It takes a visitor at Cerro de Pasco, in 
Peru, which lies at an elevation of 4,500 
meters, ten or twelve days to thoroughly 
regulate his respiration to the conditions of 
the atmosphere. In case his suffering is 
greater at first, it often happens that he is 
compelled to make a temporary change of 
residence to a point some 1,000 meters 
nearer the level of the sea. Even during 
the descent he begins to breathe more easily 
and feels brighter and stronger. 
The inhalation of air which has been 
artificially condensed, as in a pneumatic 
eabinet, produces quite similar sensations. 
An asthmatic patient placed in an atmos- 
phere where the pressure has been aug- 
mented by nearly one-half will immediately 
be enabled to breathe more freely; respira- 
tion becomes slower; his excited nerves are 
quieted, and he feels imbued with renewed 
vigor. 
The mechanical action of condensed air 
as it affects respiration is the reverse of 
the action which takes place in rarefied 
air. A higher atmospheric pressure facili- 
tates the expansion of the lungs, and the 
condensed atmosphere, by delaying the 
egress of the air expelled during exhalation, 
finally effectuates a distended condition of 
the lungs. The pulse-beats become slower 
at thé same time, and the veins, which were 
surcharged with blood under a diminished 
SCIENCE: 
161 
pressure, are now emptied more thoroughly. 
This is the cause of the decrease of conges- 
tive conditions in a pneumatic cabinet. 
The amount of oxygen which we inhale is 
increased in proportion to the increased 
condensation of the atmosphere, thereby 
enriching the blood. If the treatment is 
continued, this soon makes itself manifest 
by an increased appetite and a healthier 
complexion. ‘The invalid gains in strength 
and vitality. Respiration is facilitated 
even outside of the cabinet, and by such 
observations we perceive that the employ- 
ment of condensed air has after-effects, 
which supposition the spirometer confirms. 
A deeper and more quiet respiration has 
been observed in some eases after the elapse 
of one and even two years. 
The air which is admitted into the pneu- 
matic cabinets by means of air pumps can be 
kept at any degree of condensation. The 
cabinets, which are of various sizes, are 
arranged to admit from three to fourteen 
persons, and naturally great care is taken 
to have a good ventilation. They gener- 
ally stand in the center of a lighted hall ; 
their walls are composed of sheet iron and 
provided with windows which admit ample 
light for reading. The cabinets are used 
exclusively for the cure of catarrhal dis- 
eases, to facilitate the respiration of asth- 
matic patients, and to improve the condi- 
tion of the blood of anemic persons, in 
which cases the condensed air frequently 
proves beneficial after all other remedies 
have failed. 
The first pneumatic cabinet was estab- 
lished somewhere in the thirties, at Montpel- 
lier, by a physicist named Tabarie, who later 
gave the management of it into the hands 
of a physician. Pravaz soon followed his 
example at Lyons, and the reports of the 
two scientists as to their observations made 
on healthy and diseased persons were pre- 
sented before the French Academy and to 
the medical world in quick succession. 
