AMOUNT, COMPOSITION, \\l> CHARACTER OP ITRINE 



timial neutralization of those in solution may !><• obtained fairly accu- 

 rately by titrating the urine with \\ rmal alkali in the presence 



neutral potassium oxalate, using phenolphthalein as an indicator (Folin . 

 Tin- results may be expressed in acidity per cent in terms N 10 



\a()II required to neutralize LOO c.c. of urine [f the ammonia tion 



is added to the titration results, the total potential acidity is very closely 

 measured. 



The urine is more alkaline shortly after meals than ;it other tin. 

 since acid is being excreted by the gastric glands. It is more acid on ;t 

 meat than on a vegetable diet, and is acid during starvation because 

 protein is then the chief metabolite. In disease there is do character! 

 variation, save thai the urine is more generally acid, which may be • 

 plained by the Eacl thai in serious illness the diel is restricted. When 

 the acidity is increased, the excretion of ammonia is usually greal 

 since ammonium carbonate, the forerunner of urea, acts as an alkali and 

 neutralizes the acid radicles. This rise in ammonia, however, is 

 always proportional to the acid radicles present, since the fixed alkali 

 derived from fruits and vegetables may be sufficienl to neutralize the 

 acid formed. 



THE SOLID CONSTITUENTS 



For practical reasons we shall divide the constituents of the urine into 

 normal and abnormal. The former are presenl in the average urine in 

 amounts sufficienl to 1"' detected by ordinary means; the Latter only 

 rarely appeal' in detectable quantities. In a person eating an ordinary 

 diet the most import ant organic and inorganic constituents of the urine 



are as follows: 



Total Solids i 10 to 60 Grams) in Oni Liter oi Normal \'\ 



ORGANIC CONSTITUENTS, 25 H' <:M. INORUAK 



Urea, 20-35 L, r m. - I ium chloride NnCl ,8-15 



Creatinine, L.011.5 gin. Phosphoric aei i gm. 



Dric acid, 0.5-1.25 gm. Sulphuric acid, SO ,2-2.5 



Uippui ic acid, 0.1 l .7 gm. ra K ■ I . _ 



Other constituents (ethereal sulphat< 



alic acid, ui inary pigmi ' Jalciui i i 



1.5 2.3 gm. Magnesium Mg< i 



Ammonia Ml 

 Iron (in 



1 oropiled from Mosi 



These urinary salts are presenl in the hi 1. and an I only by 



the kidney. An investigation of the mechanism of r< 

 therefore include ;i stud} of the relationship existing 1 

 centration of the urinary salts in the Mood and in the urine. 



