404 PHYSIOLOGICAL REGULATIONS 



(cold diuresis). It may be that physiologists are merely more 

 familiar with the instances in which heat load precedes water debt ; 

 for it is easy enough to arrange for the inverse to happen by de- 

 pleting water, then administering a pyretic drug to develop a 

 positive heat load or pilocarpine to develop a negative heat load. 

 Here it may be observed how arbitrary is the distinction between 

 what the organism does during loading of its ''own free will" and 

 what is ordinarily regarded as forced upon it. 



Each interrelation of water and heat is quantitatively char- 

 acteristic of the organism. Those oxidative chemical reactions that 

 produce 0.12 gm. of water with each calorie of heat, depend upon 

 the constitution of the organism just as much as do the activities 

 whereby during loading in the desert 13 gm. of water are lost while 

 each calorie of heat is gained (line J). The only difference I 

 discern is that the former ratio is less readily modified by condi- 

 tions than the latter; it is more often seen in vitro. Actually a 

 rather constant relation was found (Adolph, '38, p. 494) between 

 heat retained and water debited. If each of these ratios had a 

 name, chosen as acceptably as ' ' respiratory quotient, ' ' the relation 

 would seem real to more individuals. When a quotient is bandied 

 about, discussed, and abbreviated, it takes on an individual 

 meaning. 



Numerous other data relate water loads (various body weights) 

 with simultaneous heat loads (various body temperatures). Tests 

 of McConnell and Yaglogiou ( '25) may be used to trace the first half 

 of curve J during exercise indoors in still air or in moving air of 

 diverse humidities. Data of Winslow et al. ( '37) and of Hardy and 

 Soderstrom ( '38) cover some of the same and many other atmos- 

 pheric conditions. Each set describes what happens in the human 

 body when heat accumulates and water depletes. Unfortunate it 

 seems that those observers did not investigate recovery states. 



In brief, two components may be experimentally loaded at one 

 time. Then both during loading and during recovery the relative 

 changes in their increments and their exchanges may be compared. 

 In examples analyzed the increments are (i) negative heat and 

 positive water, and {2) positive heat and negative water. Equiva- 

 lences in rates of their exchanges indicate certain patterns by which 

 ane component is preferentially treated or functionally linked in 

 others. 



