HEAT 



311 



Partitions of heat losses among the several paths are ascer- 

 tained in more elaborate studies (figs. 145 and 147). Loss by 

 vaporization is computed as 0.57 Calories for each kilogram of 

 water evaporated; the water evaporated, in turn, equals 90 to 100 

 per cent of the diminution in body weight. The partitions among 

 paths change enormously with heat content of the body, loss by 

 vaporization showing the largest modification ratio of any path. 

 The maximal rate of vaporization exchanges about 13 Cal./kg. hr. 

 (Adolph and Dill, '38) ; vaporization reaches a minimal rate near 



TABLE 35 

 Bates of heat exchange, Cal./Tcg. hr. Man, in diverse states 



heat balance and does not decrease further in utmost conservation 

 of heat. 



Extremes of augmentation that have been observed (in station- 

 ary states) are shown in table 35. The modification ratio of heat 

 gain in man is less than that of heat loss, and less than that of each 

 path of loss. There is evidence that gain may become much more 

 responsive to heat deficits with acclimatization to cold environ- 

 ments in individuals who are continually and variously exposed. 

 Ordinarily behavior and choice of environment are, especially in 

 heat deficits, more effective in securing recoveries than any of the 

 modifications of exchanges yet measured. 



Some conclusions that might be drawn are : (l) Eate of net heat 

 exchange during recovery is more rapid the greater the load. (2) 

 Within a limited range of loads, rates of heat loss are modified 



