40 Report OF DEPARTMENT OF BACTERIOLOGY OF THE 
Duplicate bottles containing 200cc. of sterile peptone bouillon 
and 0.1, 0.2 and 0.3 per ct. of chloroform, respectively, were 
inoculated with tcc. of a twenty-four hour bouillon culture of 
B. subtilis. The bottles were kept at 37° C. and shaken daily. At 
the end of one month no turbidity or sediment had been formed 
and there was no other evidence of growth. Cultures made from 
the bottle’ containing o.1 per ct. of chloroform showed 330 
germs per ce., which undoubtedly represented the spores present. 
A sterile cotton plug was inserted in place of the rubber cork and 
the bottle returned to the incubator. On the following day the 
bouillon was turbid and an examination showed the presence of 
immense numbers of B. subtilis. The remaining bottles were left 
for a month with their rubber stoppers in place and they remained 
without any evidence of growth. While o.1 per ct. of chloro- 
form was enough to prevent growth, the evaporation which 
occurred after the rubber stopper had been replaced by the cotton 
plug promptly reduced the concentration of the chloroform below 
the point where it was efficient. In this experiment the amount 
of solids was slight and the germicidal effect of the chloroform. 
was at its maximum. | 
The influence of added proteid is shown in the following test 
with skim-milk which contained 3 per ct. of proteids. 
Twenty litres of skimmed milk was mixed with 250cc. of slime 
from a centrifugal separator and there resulted a germ content 
of 672,500 per cc. Duplicate bottles of this mixture received 
O21, :0.3,.-0.5, 0.6,,0.8,; 1.0, 1.5, 2.0,.10:0 and 20. pen. ch ghecuuemae 
form. The bottles were: held at 32.5° C. (80° F.). The eftect of 
the chloroform upon the germ content is shown in Table I]. 
TABLE I].— GERMS PER CUBIC CENTIMETER IN CHLOROFORMED SKIM MILK.* 
| a EE a a a eT AEN AES GONE URE SEES RE LTE IE SRE AE EE SESE SE AE AES ORR ST Gi SANE Ts AN SRE SS a 
PERCENTAGE OF CHLOROFORM BY VOLUME, 












INTERVAL. 
0.1 0:3) 4.0.5 1-0 GL 0.8 184 Ofte 10. | 20. 
Initial 672, 500 ONS ty 
B hire teak A 241,000} 62,500'4,000/10, 500/1,000/1,000/ 10,000! 10 000/19 ,000 7,500 
227/000) 34,500/3,000|/38,000/2,000/1,200] 2/000] 3,000)...... “pe eels 
Slates atl xs 181,000,000! 100/1,000/ 100; 200/1,700| 140 30 
21/000,000| 1,000) ' 40 20! 100] '200/ 100} 100):.....1.. it 
eet Mae Ree 72,200 24) 21 31; 14| 13) 13 9 13| 12 
4,500 17| 268 26 9} 22 10 11 40} 22 
Sine n ees 40 39| 27 60}! 15}. 12 8 10 ee 
100 621 8 20/ 12} 68 7 3 ; 7 
G-md, dark k <4 20 30} . 37 89} 30) 25 75 32 19). PG8 
11 67| 20 331 36, 89 19 26 19 24 



x a ’ 
*Determined hy Mr. Nicholson. 
