342 
Paet II. — (2) Changes in the Composition of Milk Produced by the Milk 
Enzymes. 
According to Marfan (1), milk is not an inactive fluid, but pos- 
sesses properties vrhich are more or less characteristic of living tissues. 
For example, it gives Bordet's reaction, namely, that when the milk of 
one species of animal is repeatedly injected into the blood of an 
animal of different species the blood serum of the animal so treated 
gradually acquires the power of coagulating milk in much the same 
way as rennin. (See P. T. Muller (2) “ Yergleichende Studien Ueber 
die Gerinnung des Kaseins Durch Lab und Lactoserum.”) Human 
milk is said by Moro (3) to have the power of coagulating hydrocele 
fluid, whereas cow’s milk does not give this reaction. 
As already indicated on page 313, milk contains a number of soluble 
ferments, such as diastase (amylase), galactase, lipase, lactokinase, 
peroxidase, reductase, and catalase. 
In the present state of our knowledge we know very little of the 
actual functions of the milk ferments. According to Marfan (1), it 
is probable that the milk ferments act as stimulants and regulators 
of nutrition and that they are identical in function with the enzymes 
elaborated by the various tissues and are intended to compensate 
for the deficiency of the internal secretions of the new-born. Accord- 
ing to this author the presence of specific ferments in the milk of 
a particular animal species probably explains the value of natural 
over artificial milk feeding. 
Engel (4), in discussing Moro’s work on the influence of the milk 
ferments on nutrition, arrives at the conclusion that while these 
ferments are apparently characteristic for the milk of any partic- 
ular animal species, we can not yet come to any definite conclu- 
sions respecting their influence on animal nutrition. He calls atten- 
tion to the fact that Moro's curves showing the increase in weight of 
two sucklings both fed by the bottle, one on fresh and the other on 
boiled human milk, showed but little differences. Both curves 
showed that both children thrived less well during the second period. 
Concerning the function of the milk ferments see also Moro (5). 
On the other hand certain of these ferments bring about changes 
in the composition of milk which require some consideration in this 
connection. The following are the principal facts of interest con- 
cerning the soluble ferments found in milk and the changes which 
they effect in the composition thereof, except for what has been given 
already on this subject. 
Diastase {^amylase') of milk . — In 1883 Bechamp (6) isolated from 
human milk an enzyme which liquefles starch and converts it into 
sugar as readily as diastase. According to this author this ferment 
was obtained from successive portions of milk as soon as drawn from 
