
OTHER NEW EXPERIMENTS 183 
with calcined retorts, and yielded just the same kind 
of results as were obtained in other experiments in 
which no such precaution was taken. It cannot be 
said, moreover, that in these experiments the fertility 
was really due to the turnip infusion containing 
minute particles of cheese, since, as Professor 
Huizinga showed, soluble peptones may take the 
place of cheese without any alteration in the 
experimental results. 
Still, in all the experiments subsequently to be 
referred to (except where, as we shall see, this pro- 
cedure was purposely omitted in the first set to 
which reference will be made) I have had recourse 
to this additional precaution, and the walls of the 
vessels have been thoroughly ffamdbés before they 
have been used. Yet all that Pasteur could say 
pointing to such a necessity, as a result of his 
examination of different waters made in concert 
with M. Joubert, was that the ordinary water of a 
laboratory (tap water), with which experimental 
vessels are washed, contains Bacteria and _ their 
germs ; and that vessels which were allowed sub- 
sequently to drip and dry, might or would contain on 
their walls some germs able to withstand a tempera- 
ture of ‘100° C., at least, when in the moist state 
during several minutes” (Comptes Rendus, 
July 23, 1877). This, indeed, was now supposed by 
him to be the source of the germs, which, after they 
had been boiled, were incapable of developing in an 
acid medium ; and such germs were further supposed 
by him to be spores of Bacztlz. 
How little this view is in accord with direct ex- 
