232 THE URINE. 



combination with hydrochloric acid and sulphuric acid as well, but 

 the greater portion of these two acids, as also of the phosphoric acid, 

 is found in the form of sodium and potassium salts. The ratio 

 between the two latter is usually placed at 3 : 5, in favor of sodium. 



The alkaline phosphates normally exceed the earthy phosphates 

 by one-third, and it is to be noted that the latter are, in part at 

 least, also eliminated through the intestine. 



While the greater portion of the sulphuric acid which results from 

 the destruction of albumins within the tissues of the body is found 

 in the urine in combination with inorganic bases only, a variable 

 fraction also occurs united with certain aromatic substances which 

 are formed during intestinal putrefaction. The resulting bodies are 

 spoken of as conjugate or ethereal sulphates, and normally repre- 

 sent about one-tenth of the total amount of sulphuric acid that 

 appears in the urine. They comprise the alkaline salts of phenol, 

 indoxyl, and skatoxyl, and will be considered later. 



The mineral and conjugate sulphates together are spoken of as 

 the "acid" sulphur of the urine, in contradistinction to the so-called 

 neutral sulphur, which represents a variable fraction that escapes 

 oxidation in the body and finds its way into the urine as such. This 

 comprises such substances as thiosulpburic acid, tauro-carbaminic 

 acid, sulphocyanic acid, cystin, cystei'n, ethyl sulphide, uroferric 

 acid, alloxyproteinic acid, etc. They are described in detail at 

 another place. 



In addition to the salts mentioned, a variable amount of carbo- 

 nates may be found in the urine. In man and the carnivorous ani- 

 mals this is usually small ; but in the herbivorous animals large 

 quantities are normally found, and the alkaline reaction of such 

 urines is indeed largely referable to this source. The acid occurs in 

 combination with the alkalies and the alkaline earths, and owing to 

 the presence of the latter especially the urine of such animals is 

 normally turbid. 



Of other inorganic constituents, every urine also contains iron 

 (partly in organic combination), silicates, fluorides, hydrogen per- 

 oxide, and nitrates, all of which, however, are present only in 

 traces. The nitrates are probably introduced with vegetable food, 

 and disappear from the urine during starvation. During ammo- 

 niacal fermentation they are reduced to nitrites, and later disappear. 



The quantitative variations of the inorganic constituents of human 

 urine are shown in the following table : 



Chlorides (calculated as HC1) 6.2-9.4 grammes. 



Phosphates (calculated as P 2 O 5 ) 2.5-3.0 



Sulphates (calculated as H 2 SO 4 ) 2.0-2.5 



Sodium (calculated as Na 2 O) . , 4.0-6.0 



Potassium (calculated as K 2 O) 2.0-3.0 



Ammonium (calculated as NH 3 ) 0.7 gramme. 



Magnesium (calculated as MgO) 0.5-0.6 



Calcium (calculated as CaO) 0.2-0.4 " 



