626 



SCIENCE 



[N. S. Vol. XLI. No. 1061 



cient measure of atmospheric vitiation. 

 Even as late as 1910 in tlie excellent text- 

 book of Hoffman and Raber one could 

 read that carbon dioxide 



is constantly being diffused throughout the air of 

 the room, thus rendering it unfit for use. If this 

 carbonic acid gas could be dissociated from the rest 

 of the air and expelled from the room without tak- 

 ing large quantities of otherwise pure air with it, 

 the problem of the heating engineer would be 

 simplified, but this can not be done. 



Yet Pettenkofer as long ago as 1863 

 showed clearly that carbon dioxide in it- 

 self is quite without effect in the highest 

 concentrations which it ever attains in oc- 

 cupied rooms, and during the last fifteen 

 years the researches of Pliigge, Haldane, 

 Hill, Benedict and other physiologists have 

 rendered the older and more naive view of 

 the subject entirely untenable. Their 

 studies indicate beyond any reasonable 

 doubt that the more obvious effects experi- 

 enced in a badly ventilated room are due to 

 the heat and moisture produced by the 

 bodies of the occupants, rather than to the 

 carbon dioxide or other substances given 

 off in their breath. Two fundamental ex- 

 periments have been repeated again and 

 again by these observers which alone would 

 suffice to demonstrate, as Professor F. S. 

 Lee has so well expressed it, that the prob- 

 lem of ventilation is not chemical, but phys- 

 ical — not respiratory, but cutaneous. These 

 are, first, that subjects immured in close 

 chambers, and exposed to the heat as well as 

 the chemical products formed therein, are 

 not at all relieved by breathing pure out- 

 door air through a tube ; and, second, that 

 they are completely relieved by keeping the 

 chamber artificially cool without changing 

 the air at all, and are relieved to a con- 

 siderable extent by the mere cooling effect 

 of an electric fan. 



When the New York State Commission 

 on Ventilation began its work last year it 

 seemed that in spite of the establishment 



of these broad principles the subject de- 

 served further detailed study at its hands, 

 particularly in regard to possible unde- 

 tected effects of chemical impurities and 

 in regard to the harmful influence of mod- 

 erately but not excessively high tempera- 

 tures which have received but little atten- 

 tion in earlier researches. 



The work of the N. Y. State Commission 

 was made possible by a generous gift of 

 Mrs. Elizabeth Milbank Anderson through 

 the N. Y. Association for Improving the 

 Condition of the Poor, and the members of 

 the commission are Mr. D. D. Kimball, 

 Professor F. S. Lee, Dr. J. A. Miller, 

 Professor E. B. Phelps, Professor E. L. 

 Thorndike and the writer. The experi- 

 ments so far conducted have been carried 

 out in two experimental rooms placed at 

 our disposal by the trustees of the College 

 of the City of New York and now equipped 

 so that the atmospheric conditions in one 

 room can be very closely controlled by ap- 

 paratus located in the other. In the obser- 

 vation room over one hundred different 

 subjects in groups of four have been ex- 

 posed for periods of from three and a half 

 to eight hours a day for from one to eight 

 weeks in each series of experiments, to 

 known conditions of temperature and hu- 

 midity and atmospheric vitiation and their 

 physiological and psychological reactions 

 and mental and physical eificiency observed 

 and measured by the most exhaustive 

 methods. 



The results of our experiments to date 

 have been presented before the American 

 Public Health Association at its Jackson- 

 ville meeting and may be briefly summar- 

 ized as follows : 



Even quite extreme conditions of heat 

 and humidity (86° with 80 per cent, rela- 

 tive humidity) had no measurable effect 

 upon the rate of respiration; dead space 

 in the lungs ; acidosis of the blood ; respira- 



