338 MILK. 



the food consisted of the after-crop of grass, the milk yielded 3'92 

 and 4-39-Q-, and 3'97 and 4'6.3 when potatoes were used. Payen 

 and Gasparin* found 3 '5 of of butter in the milk of a cow which 

 had been fed in the ordinary manner, and 4'87-- when the food 

 consisted of maize-cake. Dumas found that the milk of bitches 

 was on an average somewhat richer in fat when they had been fed 

 on vegetable than on animal food. 



A mere superficial mechanical investigation would be sufficient 

 to show that the milk must be poorer in fat during disease ; the 

 fact has, however, been fully confirmed by some exact analyses 

 made by Donne, Herberger, and Simon. 



I found 3'39-g- of fat in a portion of cows 5 milk, which became 

 blue when the cream had formed. Three weeks after the dis- 

 appearance of this phenomenon, the milk yielded 4*934- of fat, 

 although the animal was fed on the same food. 



No exact investigations have as yet been made on the 

 extractive matters found in milk, or in reference to the different 

 quantities in which they occur in different milk. 



In reference to the salts of the milk, it must be observed, that 

 the soluble salts consist of the chlorides of sodium and potassium, 

 alkaline phosphates, and, in addition to these, of the potash and 

 soda which are combined with the casein in the milk. The 

 insoluble salts consist of the phosphates of lirne and magnesia, 

 which principally belong to the casein (see vol. i., p. 379). No sul- 

 phates or salts of ammonia are found in fresh rnilk (see vol. i., p. 444). 

 Haidlenf found a little peroxide of iron in the ash of cows' 

 milk. 



The milk of women contains, according to the investigations of 

 most observers, from 0'16 to 0'25-g- of salts, cows' milk from 0'55 

 to 0'85 -, and the milk of the bitch from 1'2 to 1'5. 



The amount of the soluble salts in the milk is in general smaller 

 than that of the insoluble phosphates. There occur about 0*04 or 

 0'09f of soluble salts in the milk of women, and 0'21^ of soluble 

 and 0'28 -J of insoluble salts in the milk of the cow. According to 

 Dumas, the milk of the bitch contains 0*7 1-g- of soluble and 0*77o 

 of insoluble salts when the food has been mixed, and 0'45 of 

 soluble and 0*5 7 of insoluble salts, when the food consisted of 

 animal substances. Bensch found in the miik of a bitch, which 

 had been exclusively fed on meat, 1*25 2-g- of ash, of which 1*165 

 were phosphates of lime and magnesia. 



* Oompt. rend. T. 18, p. 797. 



t Ann. d. Ch. u. Pharm. Bd. 54, S. 273. 



