710 URINE. 



acetic ether is not so good, and alcohol, chloroform, and water are even 

 less valuable. The very dilute solutions show a pink color; but on greater 

 concentration they become reddish orange or bright red. They do not 

 fluoresce either directly or after the addition of an ammoniacal solution 

 of zinc chloride; but they have a strong absorption, beginning in the 

 middle between D and E and extending to about F, and consisting of two 

 bands which are connected by a shadow between E and 6. Concentrated 

 sulphuric acid colors a uroerythrin solution a beautiful carmine red; 

 hydrochloric acid gives a pink color. Alkalies make its solutions grass 

 green, and often a play of colors from pink to purple and blue is observed. 

 PORCHER and HERVIEUX l claim that uroerythrin is a skatol pigment. 



In preparing uroerythrin according to GARROD, the sediment is dissolved 

 in water at a gentle heat and saturated with ammonium chloride, which pre- 

 cipitates the pigment with the ammonium urate. This is purified by repeated 

 solution in water and precipitation with ammonium chloride until all the urobilin 

 is removed. The precipitate is finally extracted on the filter in the dark with 

 warm water, filtered, then diluted with water, any hsematoporphyrin remaining 

 being removed by shaking with chloroform ; the precipitate is then faintly acidi- 

 fied with acetic acid and shaken with chloroform, which takes up the uroerythrin. 

 The chloroform is evaporated in the dark at a gentle heat. 



Volatile fatty acids, such as formic acid, acetic acid, and perhaps also butyric 

 acid, occur under normal conditions in human urine (v. JAKSCH), also in that of 

 dogs and herbivora (SCHOTTEN). The acids poorest in carbon, such as formic 

 acid and acetic acid, are more constant in the body than those richer in carbon, 

 and therefore the relatively greater part of these pass unchanged into the urine 

 (SCHOTTEN). Normal human urine contains besides these bodies others which 

 yield acetic acid when oxidized by potassium dichromate and sulphuric acid 

 (v. JAKSCH). The quantity of volatile fatty acids in normal urine calculated as 

 acetic acid is, according to v. JAKSCH, 0.008-0.009 gram per twenty-four hours; 

 according to v. ROKITANSKY, 0.054 gram; and according to MAGNUS-LEVY 

 0.060 grarn. The quantity is increased by exclusively farinaceous food (ROKI- 

 TANSKY), in fever and in certain diseases, while in others it is diminished (v. 

 JAKSCH, ROSENFELD). Large amounts of volatile fatty acids are produced in the 

 alkaline fermentation of the urine, and the quantity is 6-15 times as large as in 

 normal urine (SALKOWSKI 2 ). Non-volatile fatty acids have been detected as 

 normal constituents of urine by K. MORNER and HYBBINETTE. S 



Paralactic Acid,. It is claimed that this acid occurs in the urine of healthy 

 persons after very fatiguing marches (COLASANTI and MOSCATELLI). It is found 

 in larger amounts in the urine in acute phosphorus-poisoning or acute yellow 

 atrophy of the liver (SCHULTZEN and RIESS), in pregnancy (UNDERBILL), and 

 especially abundant in eclampsia (ZWEIFEL and others). According to the 

 investigations of HOPPE-SEYLER, ARAKI, and v. TERRAY lactic acid passes into the 

 urine as soon as the supply of oxygen is decreased in any way, arid this probably 

 explains the occurrence of lactic acid in the urine after epileptic attacks (!NOUYE 

 and SAIKI) . MINKOWSKI 4 has shown that lactic acid occurs in the urine in large 

 quantities on the extirpation of the liver of birds. 



1 Journ. de Physiol., 7. 



2 v. Jaksch, Zeitschr. f. physiol. Chem., 10; Schotten, ibid., 7; Rokitansky, Wien. 

 med. Jahrbuch, 1887; Salkowski, Zeitschr. f. physiol. Chem., 13; Magnus-Levy, Sal- 

 kowski's Festschrift, 1904; Rosenfeld, Deutsch. med. Wochenschr., 29. 



3 Skand. Arch. f. Physiol., 7. 



'Colasanti and Moscatelli, Moleschott's Untersuch., 14; Schultzen and Reiss, 



