Apkil 30j 1915] 



SCIENCE 



627 



tory quotient ; rate of digestion and rate of 

 heat production (both measured by oxygen 

 consumption) ; protein metabolism (meas- 

 ured by determinations of creatinine in the 

 urine) ; or skin sensitivity. 



On the other hand, the working of the 

 circulatory and heat regulating machinery 

 of the body was markedly influenced by 

 even a slight increase in room temperature, 



iT7.M 



F/tHK. 



Fig. 1. Eelation between Eoom Temperature 

 and Average Rectal Temperature of all subjects 

 at end of day. 



as, for example, from 68° to 75° with 50 

 per cent, relative humidity in both cases. 

 In a hot room (86° — 80 per cent, relative 

 humidity) the rectal body temperature usu- 

 ally rose during the period of observation; 

 in a warm room (75° — 50 per cent, relative 

 humidity) it remained on the whole about 

 constant; in a cool room (68°— 50 per cent, 

 relative humidity) it fell. The average 

 body temperatures attained under these 



three room conditions were 37.41°, 36.99° 

 and 36.73°, respectively. So the reclining 

 heart rate rose in the hot room to a final 

 average of 74 beats per minute and fell 

 in the cool room to a final average of 66 

 beats (the warm condition not being com- 

 parable in this case). I use the terms hot, 

 warm and cool throughout for the three 

 temperatures and humidity combinations 



Fig. 2. Eelatioa between Boom Temperature 

 and Average Eeelining Pulse Eate of all subjects 

 at end of day. (High value at 75° due to pre- 

 ceding physical work not duplicated at other tem- 

 peratures.) 



cited above. The increase of heart rate on 

 passing from a reclining to a standing 

 position became greater (by an average of 

 7 beats) during a sojourn in the hot room; 

 while it became less by an average of 3 

 beats in the warm room and by an average 

 of 7 beats in the cool room. The systolic 

 blood pressure was slightly decreased in 



