698 
bodies it contains known as 44 colostrum corpuscles.” It is not so 
sweet as milk, is strongly alkaline in reaction, of a specific gravity 
of 1.030 to 1.010, and is rich in salts and proteids. 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 44 colostrum 
corpuscles.” 
Cl tu f i strum . — According to Pfeiffer’s analysis, the 
composition of colostrum is as follows : 
Per cent. 
Proteid 5. 71 
Fat * 2. 04 
Sugar 3. 74 
Salts 0. 25 
Water. 
88.23 
Calorie value per kilogram, 577.1 1 calories. 
100.00 
The colostrum corpuscles are very abimdant during the first few 
days, but under normal conditions disappear after the tenth or 
twelfth day. 
F' cti of c l strum < — The exact role of the colostrum is not as 
yet fully understood. We may infer from the nature of its composi- 
tion and its proteids that it ftirnishes 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 pin-pose is proven by its being the first secretion not only of 
the human breast but of that of all mammals. 
Physi ' l t istii s f womans milk. — With 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 
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 fiocculent precipitate, and 
its proteids are hot 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 44 foremilk ” is relatively thin, the middle portion richer, 
and the 44 strippings ” richest of all in fat content. Owing, more- 
over, to faulty methods, previous analyses of woman's milk have been 
