204 THE FLUIDS. 



Water 883.6 



1. Caseine 34.3 



2. Sugar of milk (lactine) and extractive matters . 48 J2 



3. Fixed salts 2.3 



4. The butter (fat) is derived from the milk-globules, and 



makes up the remaining 25.3 parts in 1,000. 



1. The amount of caseine in woman's milk is greater after animal 

 than after vegetable food. It is, however, less abundant than in 

 cow's milk, the latter containing 41.6 (Playfair) in 1,000. The 

 coagulum is also less dense, and therefore more easily digested by 

 the infant. L'Heritier found over 50 per cent, more caseine in the 

 milk of the brunette than in that of the blonde. 



2. Woman's milk contains more sugar than that of the cow; the 

 latter containing 34 to 43 in 1,000. L'Heritier also found that the 

 milk of the brunette contains more sugar than that of the blonde, 

 in the proportion of 7 to 5.85. It is increased by a vegetable diet. 

 (Dumas and Bensch.) Diseases especially syphilis do not appear 

 to modify its amount, nor does either an abundant or an insuffi- 

 cient diet. 



3. The salts are less than one-half as abundant in woman's milk 

 as in that of the cow; the latter containing 5.5 to 8.5 in 1,000. The 

 difference, however, more especially affects the insoluble salts be- 

 longing to the caseine, and which are diminished with its diminu- 

 tion. The principal salts are the chlorides of sodium and potassium, 

 and phosphates of the alkalies, lime, and magnesia, besides the alkali 

 combined with the caseine. 



4. The fat (butter) of woman's milk is supposed to be richer in 

 oleine than that of cow's milk. It is increased by fatty food. The 

 whole amount of fat is much less than in cow's milk (the latter 

 containing 45 in 1,000), and remains nearly the same through the 

 entire period of lactation. The milk first drawn from the breasts 

 is poorer in fat than that flowing afterwards. The fat also dimin- 

 ishes in diseases. 



Albumen has been detected in milk in case of inflammation of 

 the lacteal gland. But doubtless mere congestion may cause it to 

 appear, a transudation being thus mixed with the normal secretion. 

 Urea may occur in the milk in Bright's disease of the kidney. 

 Iodide of potassium may also pass into the milk, but it has not 

 been proved that other medicinal substances can. 



The quantity of milk secreted by a healthy nursing- woman, from 



