CORRELATIVES OF WATER CONTENT 



221 



cuses have been put forward as to why changes of dilution do not 

 parallel changes of volume. Each dilution, like each volume of 

 distribution, is a separate and distinct measure bearing an indi- 

 vidual relation to body load of water. 



It is possible also to infer how much of each non-aqueous sub- 

 stance {e.g., chloride) leaves or enters the circulating blood (a) by 

 comparison with the dilution of some one {e.g., protein) that is in 

 those circumstances believed not to leave or enter, or (b) by com- 



•^40 



+4 +8 ^\^ -^16 



l/Hb— percent 



Fig. 125. Increment in dilution of serum or plasma (% of initial) in relation to 

 simultaneous increment in dilution of hemoglobin in whole blood (% of initial). Dog. 

 Since A/Hb is approximately equal to AW of the whole body (fig. 124), the abscissae 

 here might be considered as total water load. 1/VisCs is the increment in reciprocal 

 of serum viscosity; 1/ECa is the increment in reciprocal of serum electrical conductivity; 

 etc. Q represents hypothetical equality of dilutions between ordinates and abscissae. 

 Each point is the mean of 2 to 10 (usually 8) analyses on as many individuals that were 

 given water repeatedly by stomach. Data of Greene and Eowntree ('27). 



parison with the changes in one of the measured volumes of distri- 

 bution. In the intact body, only such relative estimates are avail- 

 able. 



The above studies are confined to water increments by water 

 privation and by administering water by stomach or vein. Com- 

 parisons may be obtained in blood and serum of dogs that have been 

 water-loaded by any other means. A favorite type of load that has 

 been investigated is in the state following intestinal obstruction 

 (Haden and Orr, '23). Others are the loss of gastric juice (Gamble 

 and Ross, '25), loss of pancreatic juice (Gamble and Mclver, '28), 



