4QO THE INORGANIC CONSTITUENTS OF THE URINE. 



and is produced from tyrosin (by the action of microorganisms?) within the 

 body and then passes over into the urine. 



THE INORGANIC CONSTITUENTS OF THE URINE. 



The inorganic constituents of the urine either are taken into the 

 body as such with the food and pass unchanged into the urine, or they 

 are formed independently, inasmuch as the sulphur and the phosphorus 

 of the food are consumed and unite with bases to form salts. From 

 9 to 25 grams of salts are eliminated daily. 



During sleep, the chlorin, potassium, and sodium in the urine are greatly 

 reduced, sulphuric acid and the solid constituents of the urine generally are some- 

 what reduced, while the acidity is considerably increased. 



Sodium Morid, table-salt, 12 grams (from 10 to 13 grams) daily, 

 is increased after meals as the result of movement, of the copious drink- 

 ing of water, of increase in the amount of urine generally, of generous 

 administration of sodium chlorid, but also of potassium-salts. It is 

 diminished principally under the reverse conditions. 



Under abnormal conditions the elimination of sodium chlorid is diminished 

 in large measure in association with pneumonia and other affections attended 

 with inflammatory exudation; further, in conjunction with most febrile disorders, 

 except malaria, as well as with persistent diarrhea and sweating; constantly also 

 when the urine contains albumin and when dropsy is present. Destruction of red 

 blood-corpuscles increases the chlorids in the urine, while, on the contrary, the 

 amount of chlorin in the urine (as well as in the gastric juice) is diminished in 

 the presence of anemia, although the blood contains more chlorin than normal. 



Qualitative Estimation. Urine is acidulated in a test-tube with nitric acid, 

 and a solution of silver nitrate is added, with the result that a white, cheesy deposit 

 of silver chlorid takes place. The albumin must first be removed from albuminous 

 urine by boiling. On microscopic examination, attention should be given in the 

 evaporated preparation to the terrace-like arrangement of the cubes of sodium 

 chlorid; and, at the same time, also to the rhombic prisms of sodium-chlorid urea. 



Quantitative Estimation, according to the method of Habel and Fernholz: 

 15 cu. cm. of the mixture of urine and baryta are acidulated, after neutralization, 

 with 10 drops of dilute nitric acid having a specific gravity of 1 1 19, and a solution 

 of silver nitrate, of which i cu. cm. fixes 10 mg. of sodium chlorid or 6.065 of 

 chlorin, is added so long as a precipitate of silver chlorid is observed to take 

 place. Then a small portion is filtered into a test-tube, and a test is made to 

 determine whether turbidity results from addition of one or two drops of the 

 silver-solution. If this be marked, the whole amount is poured back into the 

 beaker, p.i cu. cm. of the silver-solution is added, and the test is repeated until 

 the turbidity produced by two drops of the silver-solution is no longer particularly 

 distinct. Now an equal amount is filtered into a second test-tube, and two drops 

 of a one per cent, solution of sodium chlorid are added. If the turbidity is equally 

 marked with that produced by two drops of the silver-solution, the correct point 

 has been reached. Next, exactly so many cubic centimeters of the silver-solution 

 are added to a new specimen acidulated with 10 drops of the nitric acid; and the 

 intensity of the turbidity in the filtrate induced by two drops of silver-solution 

 is compared with that induced by two drops of the one per cent, solution of sodium 

 chlorid. If the turbidity caused by the sodium chlorid is the greater, 0.05 cu. cm. 

 less of the silver-solution is added, and the turbidity of the filtrates is compared. 

 Then so much more or less of the silver-solution is aclded as represents the differ- 

 ence between the two points last found; and this is continued until an equal 

 amount of silver nitrate and sodium chlorid produce equal turbidity in the filtrate. 



Titration of the chlorids according to the Freund-Topfer modification of 

 Mohr's method: Ten cubic centimeters of urine are diluted to 25 cu. cm., and 2.5 

 cu. cm. of a mixture of 3 parts of acetic acid, 10 parts of sodium acetate, and 100 

 parts of water are added. Next, a few drops of a 10 per cent, solution of potas- 

 sium bichromate are added, and titration is practised with the silver-solution 

 (14.63 grams in 500 cu. cm. of water), until the well-stirred yellow fluid retains 



