The protallmmens are acid bodies, soluble in 50 per 

 cent, alcohol, insoluble or little soluble in water. At 

 ordinary temperature they saturate alkalies but not acids. 



The synto-jprotalbumens have a neutral reaction. At 

 ordinary temperature they do not unite with alkalies, 

 but mineral acids. They act, therefore, as bases. They 

 are insoluble in water, soluble in hot 50 per cent, al- 

 cohol, from which solution they may be obtained on 

 cooling. The main constituent of the albumen of former 

 investigation, is identical with the stroma albumen which 

 envelopes the butter globules. 



These investigations give us an entirely new picture 

 of the constitution of milk. The hitherto known casein, 

 albumen and lacto-protein, do not exist, and these names 

 should, therefore, not be used in reporting the results of 

 the analysis ; instead, it is better to class them under the 

 general denomination of " albuminates." 



III. The milk-fats appear as minute globules which can be re- 

 cognized merely with the aid of the microscope. Each of these 

 globules is surrounded by a thin film of stroma albumen (not ca- 

 sein). Their diameter varies considerably. Specific gravity and 

 melting point vary likewise with race and quality. 



The fats are triglycerides, derived mainly from stearic, pal- 

 mitinic and oleic acids ; aside from these the following are to be 

 mentioned : myristine, iutine, hutyrine, capronine and capryline. 

 The chemical composition varies considerably with the food on 

 which the animal is kept, likewise the color, which, during the sum- 

 mer is yellow, while during the winter it appears more white. 

 Fresh milk-fat is a semi-fluid mass of faint taste and odor. 



IV. Milk sugar (CizHujOh -|- HjO) crystallizes when pure in 

 rhombic prisms, which are not changed when kept in dry air. It 

 feels hard and gritty between the teeth. It is insoluble in absolute 

 alcohol and ether, soluble in 6 pts. of cold, and 2.5 pts. of boiling 

 water. Its taste is only slightly sweet. Its specific gravity varies 

 from 1.543 to 1.548. In the polariscope it shows birotation. 



