VARIABILITIES OF WATER RELATIONS 



81 



subtrahend of gains and losses (§4), which in turn are sums of 

 exchanges by several paths. The interrelations among the rates 

 of exchange are indices to regulations. Does each rate vary at 

 random? Or does path pi compensate for the vagaries of ps'? Or 

 is pi positively correlated with ps at any one time? Thus, Rown- 

 tree ('22, p. 131) says: ''The total output of water is determined 

 by the total intake." Is there evidence that pi is an independent 

 variable, while p2 behaves in accord with it ? 



In the data of figure 44 there is found no correlation between 

 ingestive gain and urinary loss. In short periods of time also 



3 



p-c -I +1 



Wa-fcer Load 



Fig. 47. Frequency of occurrence of diverse water loads (% of Bq) when measured 

 at hourly intervals (A) compared with rates of water exchange (% of Bo) at diverse 

 water loads (B, C, D). A represents data from table 12, row 2. B, net rate in first 1.0- 

 hour of recovery, from figure 16. C, total rate in first 1.0-hour of recovery, from figure 

 13. D, total rate in stationary state, from figure 29. 



(fig. 45) there is no correlation between the two, since ingestion 

 did not occur. Even if there were a correlation, there is no way 

 of ascertaining, I believe, whether pi influences p^, or vice versa, or 

 whether both are coordinated by some other factors. 



Very often dogs exhibit rates of urinary loss greater than the 

 average at 0.5 to 1.0 hours after each spontaneous ingestion of 

 water. It is possible to say that increased intake results, after a 

 lag, in increased output. The events form a sequence. Another 

 correlation found is that ingestion follows low rates of loss. In the 



