O'SHEA — ASPECTS OF MENTAL ECONOMY. 155 



It is apparent at a glance that so far as breathing space alone 

 is concerned our students are on the whole well off. But the 

 method of heating determines in largest degree the oxygen value 

 of the atmosphere of any room which is much used. One heated 

 •by steam, with no provision for the entrance of fresh or the 

 exit of expired air, is quite certain to be improperly oxygenated, 

 be it ever so spacious ; and people living therein are likely to 

 experience sooner or later a decrease in their energies. About 

 one-third of our students reported that their rooms were heated 

 by steam, over one-half were favored with hot air ; while fifty- 

 four were kept warm in the old-fashioned way, by coal and 

 wood stoves. It is probable that the most satisfactory method 

 of heating, regarded from the point of view from which we are 

 considering the subject, is by hot air, where the wholesomeness 

 of the atmosphere is more easily secured. On entering a house 

 in winter it is not difiicult to detect whether it is heated in 

 this or in some less hygienic manner. It may be added here 

 by way of exhortation that students occupying apartments 

 heated by steam or by stoves must give especial attention to ven- 

 tilation. And this is as necessary at night as during waking 

 hours ; for it seems, as Richards says, 1 that during sleep the or- 

 ganism stores up oxygen which is to be utilized in generating 

 force for the activities of the following day. 



The effect of inadequate ventilation is readily apparent in 

 lessened vigor of mind and body, and there can be no doubt that 

 mental acumen and endurance in some cases, and lethargy and 

 dullness in others, find their explanation in the quality of air 

 habitually inspired. It may be remarked in passing that this 

 subject needs attention from university authorities as well as 

 from students themselves. A class-room filled full of seekers 



!The Northwestern Monthly, Vol. VIII, July, '97. 



