352 
perature of 36.55° C. The following are the results of his measure- 
ments : 
Time 
(minutes) . 
Remain 
(grams) . 
Product. 
4 
0.08 
0.32 
6 
. 05 
.30 
9 
.033 
.30 
11 
.024 
. .26 
12 
.019 
.23 N 
14 
.0175 
.25 
20 
.013 
.26 
25 
.01 
.25 
30 
.007 
.21 
35 
.007 
.25 
50 
.005 
.25 
70 
.004 
.28 
80 
.0032 
.26 
100 
.0028 
.28 
120 
.0025 
.30 
180 
.00185 
.33 
240 
.0017- 
.41 
The influence of various other factors, such as the reaction of the 
milk, the action of salts, the effect of ultraviolet rays, and the action 
of various organic substances on the rennin coagulation of milk has 
also been the subject of numerous investigations. It is ofttimes a 
difficult matter to determine whether these various influences are 
exercised toward the ferment itself or whether they react on the milk 
or participate only in the second phase of the rennin coagulation. 
The further consideration of such agents is beyond the scope of this 
communication. Finally, it should be observed that Hillman (50) 
has studied the rennin coagulation of milk in its practical aspects. 
This author has found that the milk of fresh cows is better suited 
to the rennin coagulation than the milk of cows which are nearly 
dry. In his opinion this is probably to be explained by the diminu- 
tion in the calcium content of milk during the period of lactation. 
He found, further, that the degree of acidity of milk in relation to 
the calcium content is an important factor. According to this 
author a high calcium content and high acidity prevail at the begin- 
ning of lactation and are usually accompanied by high total albumin 
and a high caseinogen content, all of which conduce to a large yield 
of paracasein. He also finds that the time of coagulation and the 
yield of paracasein are independent of one another; generally, how- 
ever, a short coagulation time and a large yield of paracasein are 
associated. Strong dilution of the milk with water tends to diminish 
the yield of paracasein, whereas the addition of soluble calcium salts 
tends to increase it. 
