WATER RELATIONS OF MAN 



97 



One such is that rapid drinking would allow the loss of the new 

 water by diuresis, while slow drinking avoids such an effect of 

 sudden accession. But when tested, the small diuresis that follows 

 slow voluntary drinking is not significantly augmented when water 

 equivalent to two-thirds of the deficit is forced down at once. 



At diverse water loads (fig. 59) the rates of gain differed in 

 absolute magnitude. A high correlation between them is evident, 

 and the mean rates of initial drinking are proportional to the 

 deficits. 



+20 



-ao 



^ 



-80 



Hours 

 Fig. 58. Eelative water load in relation to time. The amounts drunk are computed 

 as percentages of the deficits (loads) that initially prevailed for all tests in which the 

 deficits are 2% or more of Bj. The numbers in parentheses indicate how many tests 

 are averaged. A, dog in laboratory; B, man in desert; C, man in laboratory. At 0.5- 

 hour, the difference between desert and laboratory is shown by the t test of Fisher to be 

 significant with a P < 0.01. Data of Adolph and Dill ('38), and Adolph ('39a). 



To say that the rate of water intake is a psychological measure- 

 ment, neither adds to nor subtracts anything from the result. No 

 matter how many conditionings and experiences may influence the 

 drinking, evidently the choice of rates is not unlimited. Moreover, 

 most features of ingestion (table 15) are reproducible not only in 

 one individual but among individuals. 



The behavior concerned in water drinking belongs to the cate- 

 gory of "operant" behavior (Skinner, '38), the responses of inges- 



