276 BIOLOGICAL PROBLEMS 







which they ventilated their huts. It was a usual ex- 

 perience (in the early days of the war) to find several of 

 the men of a fully-occupied hut, in which all the win- 

 dows were closed, to be coughing and sneezing; but 

 when, at the same time and in the same large camp, 

 there was another unit trained to more open-air con- 

 ditions, with several open windows to each hut, there 

 was generally an entire absence of those symptoms. 

 There was a freshness in the atmosphere of these 

 latter huts that contrasted pleasantly with the stuffy 

 state of the air in the other huts inspected. This was 

 very impressive evidence of the close relationship 

 between fresh air and efficiency in the army for 

 catarrhal conditions not only lower the efficiency of 

 the men who are able to carry on, they prevent a cer- 

 tain number from doing so; and, by conferring a 

 predisposition, they are frequently the precursors of 

 serious invaliding from other diseases. These catarrhal 

 conditions lower resistance to several forms of disease, 

 and have been intimately associated with the incidence 

 of spotted fever and pneumonia among our troops. 

 One cannot but be struck by the general coincidence 

 of the prevalence of spotted fever with a high sick- 

 rate from catarrhal affections. Furthermore, histories 

 of outbreaks of spotted fever and pneumonia in civil 

 communities usually disclose an association with over- 

 crowding and lack of ventilation. And so it would 

 appear that, whenever catarrhal conditions are unduly 

 prevalent amongst our soldiers, it is wise to let this 

 fact serve as a signal for increased ventilation, to 

 treat it as raising the possibility of the presence or 

 early appearance of more serious disease. 



In the army hut the authorized mobilization scale 

 of floor space per man is only 40 square feet; therefore, 

 when it is fully occupied, it is necessarily very crowded, 

 and unless the air is frequently renewed it soon be- 



