
ot DD, ae 
& lk ee ee 
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CONCLUDING EXAMINATION 195 
no fermentation subsequently occurred. In the other 
sixteen trials more or less distinct fermentation 
supervened—though in some the signs of change 
before opening the vessels were only slight. The 
characters of the organisms presented by these 
different fluids will be referred to in the next section. 
On another occasion, five tubes were charged 
with a neutralised hay-infusion, and after the tubes 
were sealed they were heated to 257° F. (125° C.) 
for thirty minutes. They were exposed to an 
incubating temperature of 110 to 115° F., and on 
the fourth day the fluids in each were found to be 
slightly turbid. On examination they showed an 
abundance of Torulz mixed with Bacteria. 
Six trials with neutralised Ao¢azo-infusion, having 
a specific gravity of 1o11, yielded no evidence of 
fermentation. Twice infusions were heated to 
e460 -F( 190. ©.) and four times to 230: Fe. (rio C.} 
for 30 minutes. 
Sixteen trials with a neutral cucumder-infusion, 
having a specific gravity of 1003, heated to tempera- 
tures varying from 221°-248° F. (105°-120° C.) for 20 
minutes were also attended by uniformly negative 
results. 
But in forty experiments with good cow’s mzlk 
heated in closed tubes half full of air to 230° F. 
(110° C.) for 5-60 minutes, and also in five other 
experiments in which the milk was heated to 240° F. 
(115°°5 C.) for 10 minutes, fermentation more or less 
marked occurred in each case in from 2-10 days. 
The great variation in these results, especially with 
