MEANS OF DEFENCE AGAINST MICROBES, 247 
In fact, direct experiments, made with a maximum 
registering thermometer enclosed in the dough, shows 
that the internal temperature of the loaf, that of the 
crumb, rarely rises to 100°. We know that this tem- 
perature does not suffice to destroy most microbes, 
still less their germs, for which a temperature of from 
115° to 160° is necessary. 
In 1884, Bouvet, a chemist, and Préaubert, a pro- 
fessor at the Lycée, were commissioned by the munici- 
pality of Angers to make a microscopic examination of 
numerous specimens of well-water used by bakers in 
their trade in different parts of the town. The exami- 
nation of deposits, either obtained spontaneously by 
allowing the water to stand for twenty-four hours, or 
by testing the water with osmic acid, in accordance 
with Certes’s process, almost invariably revealed the 
presence not only of the ova of ascarides, but of 
numerous microbes-—-some of them harmless, like 
Bacterium termo ; others doubtful, on account of their 
forming chains like the micrococcus (two species of 
different form), and resembling Micrococcus diphthe- 
ricus. Now, croup may be regarded as endemic at 
Angers. In four wells out of the twenty-five ex- 
amined these microbes were found in great numbers. 
It must be noted that micrococci are not found in 
strongly aérated water, but only in that of which 
the organic deposit is abundant. 
Well-water must, therefore, be generally condemned, 
both for drinking purposes and for the making of 
