CH. XII.] 



ACID EXCRETION. 



275 



have been investigated by Palmer and Henderson,* who 

 find that in certain types of the disease ("High Ratio") 

 there is a remarkable increase in R, mainly due to a deficit 

 in the excretion of ammonia. In other types of renal 

 disease the various factors are nearer to normal, as can 

 be seen from the table below. 



It would seem that an important factor in renal disease 

 is a difficulty in the excretion of ammonium salts, so that 

 to maintain the normal reaction of the blood the kidney is 

 forced to excrete an abnormally acid urine. This, in its 

 turn, may cause a further degeneration of the renal tissues. 



A further point of interest in connexion with the acidity 

 of the urine is that, according to van Slyke, the alkali 

 reserve of the body can be determined and the condition of 

 "acidosis" diagnosed from the indication given by the 

 analyses described below, f 



The method of determining the P H of urine is given on 

 p. 29. 



322. The estimation of titratable acid in urine (Cole's method). 



Principle. The urine is titrated to P H = 7-45 (the average 

 reaction of normal blood), using a large form of Cole and Onslow's 



* Journ. of Biol. Chem., xxi., p. 37. 



f A full account will be found in the following papers : Fitz and van 

 Slyke, Journ. of Biol. Chem., xxx., p. 389. Van Slyke, ibid, xxxiii., p. 271. 



