306 



CHEMISTRY OF THE PROTEIDS 



CHAP. 



TABLE BY F. N. SCHULZ SHOWING THE PERCENTAGE IN WHICH 

 VARIOUS HEAVY METALS HAVE BEEN FOUND IN COMBINATION 

 WITH EGG-ALBUMIN. 



* Values inconstant. f Precipitated with basic lead acetate. 



Precipitated with neutral lead acetate. 



Galeotti, 6 by employing Gibb's method of representing geometrically 

 the thermodynamic principles governing a pluriphasic system, has 

 succeeded in solving the problem of the equilibrium between the 

 different phases of egg-albumin or serum-albumin and CuSo 4 or AgN0 3 

 by a graphic method, for a temperature between 14 and 16. If the 

 centesimal composition of a given complex has been ascertained, it is 

 possible to at once determine into how many phases such a complex 

 may divide, and also what the composition of each phase must be. 7 

 Galeotti has arrived at the conclusion that the salts of the heavy 

 metals with the albumins are not true compounds in constant propor- 

 tions according to the theory of valency. The insoluble compounds 

 which are formed on bringing together solutions of albumin with heavy 

 metals, and which are usually called metallic albuminates, are loose 

 compounds with varying constitutions. 



As the combinations of the heavy metals with the albumin are 



1 Schwarzenbach, Liebig's Annalen, 133. 125 (1865). 



2 Diakonow, Hoppe-Seylers med. chem. Unters. 1867, p. 228. 



3 Fuchs, Liebig's Annalen, 151. 372 (1869). 



4 Commaille, Moniteur scientific, Oct. 1866. Abstracted in Jahresb. u. Fortschr. d. 

 Chemie, v. Will, 1866 (Giessen, Ricker, publisher). 



5 Loew, Pfluger's Arch. 31. 393 (1883). 



6 G. Galeotti, Zeitschr. f. physiol. Chem. 40. 492 (1904). 



7 The reader will find a concise account of Gibb's principle as elaborated by Bakhuis- 

 Eoozeboom, Rijn van Alkemade and Schreinemakers in Galeotti's paper. 



