Abstract of Chemico-Physiological Researches . 413 



D. The material (coagulating by heat, like albumen) which 

 remains dissolved in milk which has become sour, was boiled 

 with alcohol and aether, and dried. 

 Of these specimens of casein, 



A gives lO'O per cent, of ashes . 



B ... 2-0 



C ... 1-5 



D ... 2-0 



The methods of analysis being the same as in the former in- 

 stances, the results were, — 



b 



100-000 100-000 100-000 100-000 

 Protein. 

 Dr. Scherer prepared this body according to Mulder's 

 method, by solution in caustic potash liquor and precipitation 

 by acetic acid. The results with pi'otein from three different 

 sources agree very well with those of Mulder, and are as fol- 

 lows : — 



Protein from Protein from Protein from 

 crystalline lens. albumen. fibrine. 



Carbon .... 55-300 55-160 54-848 



Hydrogen . . 6-940 7-055 6-959 



Nitrogen . . . 16-216 15-966 15-847 



Oxygen^. . . . 21-544 21-819 22-346 



100-000 100-000 100-000 



As the compounds of protein do not admit of our deducing 

 any positive rational formula for protein, Liebig proposes the 

 empirical formula C^^ Hgg Ng O14, which gives a per cent, 

 composition coinciding with the results of the above analyses. 



Having thus determined the composition of the funda- 

 mental materials of the animal organization. Dr. Scherer 

 proceeds to examine the secondary tissues. These are merely 

 to be considered as products of animal life, and are not met 

 with in vegetable structures, whereas the former class exist 

 e(jually in both departments of organized nature. The sub- 

 stances to be analysed were obtained in the condition of 

 greatest anatomical purity, and carefully freed from all inter- 

 mixed fat, &c. by such chemical means as were least likely to 

 alter their own texture. Although such textures are not ana- 

 tomically homogeneous, but under the microscope still show 



