698 
bodies it contains known as ‘‘ colostrum corpuscles.” It is not so 
sweet as milk, is strongly alkaline in reaction, of a specific gravity 
of 1.030 to l.OIO, and is rich in salts and jDroteids. These proteids are 
of a nature similar to the proteids of the blood as they are coagulated 
by heat. Colostrum contains less sugar and fat than milk, and micro- 
scopically its fat globules vary in size and are interspersed with 
numerous bodies four or five times their size, known as colostrum , 
corpuscles.” 
Composition of colostrum. — According to Pfeiffer's analysis, the ! 
composition of colostrum is as follows : ! 
Per cent. ; 
Proteid 
Fat — . 
Sngar_. 
Salts _ 
Water.. 
2.04 
3.74 
0. 25 
88. 23 
100.00 
Caloric value per kilogram, 577.17 calories. 
The colostrum corpuscles are very abundant during the first few ' 
days, but under normal conditions disappear after the tenth or 
twelfth day. 
Function of colostrum. — The exact role of the colostrum is not as 
yet fully understood. IVe may infer from the nature of its composi- 
tion and its proteids that it furnishes to the newborn child during its 
adjustment to its novel surroundings the full expansion of the lungs 
and the awakening of the digestive processes, nourishment of a char- 
acter similar to that it received from the placenta as a fetus. That it 
serves a purpose is proven by its being the first secretion not only of 
the human breast but of that of all manmials. 
Physical characteristics of icoman's iniTk . — lYith the establishment 
of lactation the breast secretes a fluid of the following physical char- 
acteristics : It is of a bluish color and marked sweetish taste. Under i 
normal conditions, with the exception of some skin cocci, it is practi- 
cally sterile. These are most abundant in the foremilk.” Its spe- 
cific gravity varies from 1.026 to 1.036 (average, 1.032 at 21° C.). 
Its reaction is either amphoteric or slightly alkaline when fresh. 
Dilute acetic acid merely produces a light flocculent precipitate, and 
its proteids are not appreciably coagulated by the action of rennet. 
Composition. — The exact average composition of breast milk is 
difficult to determine, as it is subject to rather wide variations between 
normal limits and at different stages during the act of being secreted. 
Thus the “ foremilk ” is relatively thin, the middle portion richer, * 
and the ” strippings ” richest of all in fat content. Owing, more- i 
over, to faulty methods, previous analyses of woman’s milk have been • \ 
