508 
SEDGWICK AND WINSLOW. 
BACILLUS OF TYPHOID FEVER. 
]). EXTERIMENTS ON THE VIABILITY OF TYPHOID FEVER BACILLI IN EAETII 
AT VAEIOUS TEMPERATURES. 
These experiments were carried 
a rcM 
of the number of typhoid bacilli 
der to compare the conditions affecti 
in soil, with those operating on them 
organism. 
water and ice. The general method pursued was the same, the inoculation of 
inimerous small portions of a sterile medium with a pure culture of the micro- 
In each series of experiments about one hundred grains of sifted clayey 
soil were sterilized by baking for sixteen hours, on two successive days. The whole 
of the earth was then inoculated by mixing with it a bouillon culture two or three 
days old, of B. typhi, Race B; and an even distribution was accomplished by stirring 
kneading with a spatul 
The 
th, having been dried by the previous bak 
J 
)d the bouillon culture without becoming visibly damp. Fifty portions of 
tod earth of one gram each were then weighed out and placed in fifty ste 
(y test-tub 
Of 
fifty portions, ten were at once mixed with sterile 
d two check plates made from each flask. The remaining forty tubes were carried 
the coki storage warehouse or kept at the room temperature, as the case might be, 
in either condition being protected from the action of light. 
After one day, th 
da\ 
week, and two week 
tub 
were 
gram of earth was mixed 
noved and planted. In every 
hundred or nine hundred cubic 
The 
of sterile water ; and two check plates were made from the dil 
and tubing of th 
th 
nducted 
a 
gla 
chamber some three feet square, with a sliding door raised only sufficiently to admit 
of th 
bef 
perator. Control plates were made from four portions of 
ore 
the portions of 
g 
like the regular tubes 
apie 
being 
tubed and planted 
rth 
tly 
The following were the results per gram 
Colonies per Gram. 
1 
2 
14 
1 

3 
3 


4 
SCO 

The tubes of the first three series were kept at the cold storage warehouse durin 
the period of the experiment, at 0° C. Those of the fourth series were kept at the 
room temperature. The summarized average results of these four series are as 
follows: 
