178 Report oF THE CHEMICAL DkPARTMENT OF THE 
The preceding table does not show any marked influence due 
to the presence of such varying amounts of fat. 
There are more bacterial spores present than are shown in the 
results given in Table I. This is probably due to the combined 
action of a number of factors: (1) The heating of the butter 
was not high enough to kill the spores introduced from that 
source; (2) the presence of many small globules of fat in the 
cultures makes counting difficult and tends to give too high 
figures; (8) this experiment was started in midsummer, when the 
air is better supplied with spores, than in midwinter, when the 
former investigation was begun. 
A comparison of the percentages of change shown in Tables I 
and II after corresponding intervals shows the transformation 
to have been more rapid in the case of Table II. This is easily 
accounted for by the fact that here whole milk was used and the 
proportion of enzyme to nitrogen was greater than in the former 
case where the skim-milk was poorer in enzyme on account of the 
amount lost in the separator slime and in the cream. 
COMPARISON OF EFFECT OF ETHER, CHLOROFORM AND A MIXTURE OF 
BOTH UPON ENZYME ACTION, 
Milk was obtained from two cows, care being taken to brush 
and moisten the flank and udder and to steam the pail, but by 
mistake the fore-milk was used in the case of one cow. The milk 
was taken directly to the laboratory and plates made, which 
later showed a germ content of 2719 per cc. The fat content of 
the milk was 4.5 to 5 per ct. Duplicate bottles were prepared in 
three series containing (1) 15 per ct. of ether, (2) 3 per ct. chloro- 
form and (8) a mixture containing 2.9 per ct. of ether and 2.1 
per ct. chloroform, The bottles were kept at 99° F, (87° C.). 
