pl ae i ae ied 
c ° 
New YorK AGRICULTURAL EXPERIMENT STATION. 57 
four and seven days, respectively. There were many thousands 
of bacteria per cc. present at the end of three months but the 
colonies developed so thickly on the plates that accurate count- 
ing was not possible. Plates were prepared from only one of 
the bottles at the end of six months and 188,700 per cc. were 
found. It was difficult to obtain satisfactory samples for chemical 
analysis from the curdled mass and these results were there- 
fore somewhat irregular. While the total digestion was not 
greater than in the bottles where the bacteria were destroyed by 
the chloroform, it was characterized by the presence of measur- 
able amounts of ammonia. 
No ammonia was found in any of the other bottles; the germ 
content was uniformly low and the milk did not curdle until 
after about two months. From these facts, it seems a justifiable 
assumption that, in the case of these bottles, the action of germ 
life was excluded. This must certainly have been the case with 
the bottles containing 0.5 per ct. or more of chloroform. 
The determinations of the soluble nitrogen show that, in the 
bottles containing chloroform in percentages ranging from 0.2 
to 0.7 per ct., the rate of enzym action was practically uniform, 
and at the end of 6 months there was approximately 50 per ct. 
of the nitrogen in the soluble form. The digestion in the bottles 
containing 1.0 per ct. or more of chloroform was less rapid 
from the beginning and this retardation of the enzym action 
increased with the increase in the percentage of chloroform 
present.’ In the bottles containing 2.5 per ct. of chloroform, the 
average content of soluble nitrogen at the end of 6 months was 
but 38 per ct. of the total nitrogen. 
This observed decrease of 12 per ct. in the activity of the milk 
enzyms, when comparing their action in the presence of 0.7 and 
2.5 per ct. of chloroform, respectively, was undoubtedly due to 
the unfavorable action of the higher percentage of chloroform. 
In view of these results, it is important, to know the effect ot 
such higher percentages of chloroform as were used in the cheese 
work. Accordingly, duplicate bottles were prepared contain- 
ing 2.5, 5, 10, 20 and 30 per ct. of chloroform, respectively, in 
skimmed milk. The milk had been twice passed through a cen- 
trifugal separator and contained only 0.025 per ct. of fat. One 
litre of the mixture was put into each bottle and the bottles 
Were wield at 15:5°.C. (60° B.). ; 
The soluble nitrogen and the germ content of the bottles at 
the end of various intervals are given in Table XI. 
