
THERMAL DEATH-POINTS 83 
hours to be turbid with Bacilli. At the expiration 
of 48 hours all the other 22 fluids were quite clear, 
but by the end of the third day two of them had 
become turbid, while the remaining 20 underwent 
no change. 
Here again, then, out of 27 trials with a favour- 
able nourishing fluid inoculated with desiccated 
Bacilli spores, under conditions most favourable for 
their survival,1 in only two cases where they had 
been heated merely for 12’ were they able to sur- 
vive an exposure to 212° F. ; while out of the total 
63 trials in which these ‘‘old hay germs”? (that is, 
actual spores desiccated for over five years) were 
used as the inoculating material, only once was 
there evidence that any of them could resist an 
exposure for 20’ to a temperature of 212° F.—and 
it is quite possible that this isolated positive result 
might have been due to some accidental contamina- 
tion after the heating. 
With the last microscope slip containing these 
desiccated Bacillus spores an attempt was made to 
see what the influence of 80° C. (176° F.) upon 
them would be. Some acid urine was first sterilised 
by boiling it for 10’ in a purified Lister’s receiver. 
To this some of the emulsion containing Bacillus 
spores, without any prolonged soaking, was added 
in the proportion of two minims to the ounce, as 
before. 
1 Most favourable because in their dried state, just like a parched 
pea, they might be able to withstand for a time the influence of the 
boiling water, and subsequently undergo development while in the 
incubator. 
