POTASSIUM AND SODIUM. AMMONIA. 727 



and CITRON, l the quantity of nitrates is smallest with a meat diet and greatest 

 with vegetable food. The average amount is about 42.5 milligrams per liter. 



Potassium and Sodium.. The quantity of these bodies eliminated 

 by the urine by a healthy adult on a mixed diet is, according to SALKOW- 

 SKi, 2 3-4 grams K 2 O and 5-6 grams Na 2 O, with an average of about 2-3 

 grams K 2 O and 4-6 grams Na 2 O. The proportion of K to Na is ordinarily 

 3:5. The quantity depends above all upon the food. In starvation 

 the urine may become -richer in potassium than in sodium, which results 

 from the lack of common salt and the destruction of tissue rich in potas- 

 ,sium. The quantity of potassium may be relatively increased during 

 fever, while after the crisis the reverse is the case. 



The quantitative estimation of these bodies is made by the gravi- 

 metric methods as described in works on quantitative analysis. In 

 the determination of the total alkalies new methods have been devised 

 by PRIBRAM and GREGOR, and for the potassium alone a method by 



AUTENRIETH and BERNHEIM. 3 



Ammonia. Some ammonia is habitually found in human urine and 

 in that of carnivora. As above stated (page 694), on the foimation of urea 

 from ammonia, this quantity may represent the small amount of ammonia 

 which is excluded from the synthesis to urea by being combined with 

 acids formed in excess by combustion and not united with the fixed alka- 

 lies. This view is confirmed by the observations of CORANDA, who found 

 that the elimination of ammonia was smaller on a vegetable diet and 

 larger on a rich meat diet .than on a mixed diet. On a mixed diet the 

 average amount of ammonia eliminated by the urine is about 0.7 gram 

 NHs per day (NEUBAUER), corresponding to 4.6-5.6 per cent of the total 

 nitrogen of the urine according to CAMERER, Jn As above stated, all 

 the ammonia of the urine is not represented by the residue which has 

 eluded synthesis into urea by neutralization with acids, because, as shown 

 by STADELMANN and BECKMANN, 4 ammonia is eliminated by the urine 

 even during the continuous administration of fixed alkalies. 



Ammonia exists on an average of about 0.90 milligram in 100 cc. of 

 human blood, and in different amounts in all the tissues thus far investi- 

 gated. 5 According to NENCKI and ZALESKI 6 it is abundantly formed in 



1 Schonbein, Journ. f. prakt. Chem., 92; Weyl, Virchow's Arch., 96, with Citron, 

 ibid., 101. 



2 Ibid., 53. 



3 Pribram and Gregor, Zeitschr. f. analyt. Chem., 38; Autenreith and Bernheim, 

 Zeitschr. f. physiol. Chem., 37. 



4 Coranda, Arch. f. exp. Path. u. Pharm., 12; Stadelmann (and Beckmann), Ein- 

 fluss der Alkalien auf den Stoffwechsel, etc. Stuttgart, 1890; Camerer, Zeitschr. f. 

 Biologic, 43. 



5 See Salaskin, Zeitschr. f. physiol. Chem., 25, 449, and footnote 6, page 317. 



8 Arch, des science biol. de St. Petersbourg, 4, and Salaskin, 1. c. See also Nencki 

 and Zaleski, Arch, f . exp. Path. u. Pharm., 37. 



