660 MILK. 



Milk of the Water. Solids Proteins. Fat. Sugar. Salts. 



Dog ............. 754.4 245.6 99.1 95.7 31.9 7.3 



Cat ............. 816.3 183.7 90.8 33.3 49.1 5.8 



Goat ............ 869.1 130.9 36.9 40.9 44.5 8.6 



Sheep ........... 835.0 165.0 57.4 61.4 39.6 6.6 



Cow ............. 871.7 128.3 35.5 36.9 48.8 7.1 



Horse ........... 900.6 99.4 18.9 10.9 66.5 3.1 



Ass .............. 900.0 100.0 21.0 13.0 63.0 3.0 



Pig .............. 823.7 176.3 60.9 64.4 40.4 10.6 



Elephant ......... 678.5 321.5 30.9 195.7 88.5 6.5 



Dolphin ......... 486.7 513.3 ____ 437.6 ____ 4.6 



Whale 1 .......... 698.0 302.0 94.3 194.0 9.9 



Human Milk. 



Woman's milk is amphoteric in reaction. According to COURANT 

 its reaction is relatively more alkaline than cow's milk, but it has, never- 

 theless, a lower absolute reaction for alkalinity as well as for acidity. He 

 found between the tenth day and the fourteenth month after confinement 

 practically constant results. The alkalinity, as well as the acidity, was 

 a little lower than in childbed. One hundred cc. of the milk had the 

 same average alkalinity as 10.8 cc. N/10 caustic soda, and the same 

 acidity as 3.6 cc. N/10 acid. The relation between the alkalinity and the 

 acidity in woman's milk was as 3:1, and in cow's milk as 2.1:1. The 

 actual reaction determined electrometrically is, according to Fol, 2 still 

 nearly neutral, like the other kinds of milk. ALLARIA has also arrived 

 at similar results, according to whom the tendency of human milk toward 

 alkaline reaction even in the most prominent cases never corresponds 



to a NaOH solution - 



Human milk also contains fewer fat-globules than cow's milk, but 

 they are larger in size. The specific gravity of woman's milk varies 

 between 1.026 and 1.036, generally between 1.028 and 1.034. It is highest 

 in well-fed and lowest in poorly-fed women. The freezing-point is lowered 

 on an average 0.589 C., according to WINTER and PARMENTIER S con- 

 stant at 0.55, and the molecular concentration is 0.318. 



The fat of woman's milk has been investigated by RUPPEL. It forms 

 a yellowish- white mass, similar to' ordinary butter, having a specific gravity 

 of 0.966 at 15. It melts at 34.0 C. and solidifies at 20.2 C. The fol- 

 lowing fatty acids can be obtained from the fat, namely, butyric, caproic, 

 capric, myristic, palmitic, stearic, and oleic acids. The fat from woman's 

 milk is-, according to RUPPEL and LAVES, 4 relatively poor in volatile 

 fatty acids. The non-volatile fatty acids consist of one-half oleic acid, 



1 Scheibe, cited in Bioch. Centralbl., 7, 553. 



2 Compt. rend. soc. biol. 58; Allaria, Maly's Jahresb., 39, 242. 



3 See Maly's Jahresber., 34. 



4 Ruppel, Zeitschr. f. Biologic, 31; Laves, Zeitschr. f. physiol. Chem., 19. 



