502 
SEDGWICK AND WIN SLOW 
BACILLUS OF TYniOID FEVER. 
is iiuLliiiig mysterious about the act of freezing, no mechanical crushing of bacteria- 
the |)iocess of destruction Is continuous above and below the freezing-point, dependintj- 
iipou the two main factors of time and temperature. 
Series K and III of Races B and C cover longer periods of time and higher tein- 
pcrat 
Half of the tub 
kept 
10 
o 
d half 
20^b 
marked differences appeared as the result of these two modes of treatment, and the two 
I 
sets arc averaged together in each series. The tubes were kept in these experiments 
for two weeks, one-half of them being sampled on the second and the seventh day, the 
others on the third day and the fourteenth. The tubes were, of course, protected from 
the action of light. 
■V 
Race B. 
Race C. 
Time. 
1 day 
3 clays 
7 days 
14 days 
Reduction per cent. 
Series II. Series III 
Reductiou per cent. 
Series II. Series III. 
92.2 
99.3 
99.9 
99.9 
78.7 
86.7 
99.3 
98.8 
88,4 
90.4 
94.1 
99.9 
71.0 
83.3 
89.6 
99.9 
It will be noted 
with each race the second 
sho 
greater 
d. The explanation for this lies in the fact that these expe 
carried on some time after the regular experiments on freezing 
During the intervening period the germs had been grown on i 
P 
first 
f 
perunents with each race showed 
day 
The results of 
have not b 
dinary reduction, over 99 per 
jen tabulated. The second 
while by 
of each race, Series II above, showed more moderate, but still high reduction 
third series was inoculated, a week later, the cultures, by 
bouillon, had regained their normal 
The tubes inoculated with Race D were kept for twenty-four hours only, sampl 
being planted after 3, 6, 12, and 24 h 
Series I was kept at 20" and Series II at 10 
After 3 hours. 
Series I (20°) ..... 70.S 
Series II (10°) q^^ 
C hours. 
72.6 
74.0 
12 hours. 
85.7 
87.4 
24 hours. 
88.4 
95.5 
CONCLUSIO 
bel 
From these experiments it appears that typhoid fever bacill 
few minutes' exposure 
uch as they do 
A 
arge proportion of 
killed 
the unfavorable conditions ; during the next few hours th 
3n proceeds pari passu with the duration of the 
for ^ome time. 
periment ; while a few germs 
