750 URINE. 



STEN), or simply by adding an equal volume of a saturated neutral solution of 

 ammonium sulphate (HOFMEISTER and POHL *). The precipitate consisting of 

 globulin is thoroughly washed with a saturated magnesium-sulphate or half- 

 saturated ammonium-sulphate solution, dried continuously at 110 C., boiled 

 with water, extracted with alcohol and ether, then dried, weighed, incinerated, 

 and weighed again. The quantity of albumin is calculated as the difference 

 between the quantity of globulin and the total proteids. 



Approximate Estimation of Proteid in Urine. Of the methods suggested for 

 this purpose none has been more extensively employed than ESBACH'S. 



ESBACH'S 2 Method. The acidified urine (with acetic acid) is poured into a 

 specially graduated tube to a certain mark, and then the reagent (a 2-per cent 

 citric-acid and 1-per cent picric-acid solution in water) is added to a second mark, 

 the tube closed with a rubber stopper and carefully shaken, avoiding the pro- 

 duction of froth. The tube is allowed to stand twenty-four hours, and then the 

 height of the precipitate on the graduation is read off. The reading gives directly 

 the quantity of proteid in 1000 parts of the urine. Urines rich in proteid must 

 first be diluted with water. The results obtained by this method are, however, 

 dependent upon the temperature; and a difference in temperature of 5 to 6.5 

 C. may cause an error of 0.2-0.3 per cent deficiency or excess in urines containing 

 a medium quantity of proteid (CHRISTENSEN and MYGGE). The method sug- 

 gested by TsuscHUA 3 seems to be more reliable and consists in precipitating the 

 proteid by an alcoholic solution of phosphotungstic acid containing hydrochloric 

 acid. 



Other methods for the approximate estimation of proteid are the optical 

 methods of CHRISTENSEN and MYGGE, and of WALBUM, 4 of ROBERTS and STOLNI- 

 KOW as modified by BRANDBERG, with HELLER'S test, which has been simplified 

 for practical purposes by MITTELBACH. The density methods of LANG, HUPPERT, 

 and ZAHOR are also very good. In regard to these and other methods we refer to 

 HUPPERT-NEUBAUER'S Harn-Analyse, 10. Aufl. 



There is at present no trustworthy method for the quantitative estimation 

 of proteoses and peptone in the urine. 



Nudeoalbumin and Mucin. According to K. MORNER traces of urinary 

 mucoids may pass into solution in the urine; otherwise normal urine con- 

 tains no mucin. There is no doubt that there may be cases where true 

 mucin appears in the urine; in most cases mucin has probably been mis- 

 taken for so-called nucleoalbumin. The occurrence, under some circum- 

 stances, of nucleoalbumin in the urine is not to be denied, as such sub- 

 stances occur in the renal and urinary passages; still in most cases this 

 nucleoalbumin, as shown by K. MORNER, 5 is of an entirely different kind. 



All urine, according to MORNER, contains a little proteid and in 

 addition substances precipitating proteid. If the urine freed from salts 

 by dialysis is shaken with choloroform after the addition of 1-2 p. m. 

 acetic acid, a precipitate is obtained which acts like a nucleoalbumin. 



1 Hammarsten, Pfliiger's Arch., 17; Hofmeister and Pohl, Arch. f. exp. Path. u. 

 Pharm., 20. 



2 In regard to the literature on this method and the numerous experiments to deter- 

 mine its value, see Huppert-Neubauer, 10 Aufl., 853. 



3 Christensen, Virchow's Arch., 115; Tsuschija, Centralbl. f. Med., 1908. 



4 Detusch. med. Wochenschr., 1908. 



5 Skand. Arch. f. Physiol., 6. 



