On Spontaneous Generation, By Henry J, Slack, 167 
made fecund if we communicate to them a slight alkalinity. The 
novelty introduced by Dr. Bastian in having recourse to a tem- 
perature of 50° C. is only apparent, since this condition is super- 
fluous. There is then between us only a difference in the inter- 
pretation of facts common to both. Dr. Bastian says these facts 
prove spontaneous generation, and I reply not at all, they only 
demonstrate that certain germs of inferior organisms resist a tem- 
perature of 100° C. in neutral and slightly alkaline solutions, 
doubtless because under such conditions their envelopes are not 
penetrated by the water, and that they are so if the medium in 
which they are heated is slightly acid. In reference to this I will 
recall that the workmen of Eouen, as M. Pouchet informed us, 
noticed that certain seeds attached to wool coming from Brazil 
germinated after four hours' exposure to boiling water, and 
M. Pouchet proved that when the germination occurred after 
such treatment the grains had preserved their natural size, their 
hard horny envelope not having been penetrated by water or 
steam ; when the contrary was the case, germination was impos- 
sible. With regard to germs disseminated in atmospheric dust, 
I proved that they perish in an acid medium at 100° 0., but 
they remain fertile if the medium is alkaline. (See p. 65 of my 
paper.) 
If Dr. Bastian wishes to assure himself of his errors of inter- 
pretation he can easily do it. He obtains bacteria by saturating 
boiled urine with potash. I simply suggest that instead of em- 
ploying an aqueous solution of potash, he should drop into the 
urine solid potash after making it red hot, or even only to 110° C. 
His experiment will then never succeed ; that is, he will obtain 
no formation of bacteria in urine exposed to 30°, 40°, or 50° G. 
The conclusion he has drawn from our common experiments is 
thus inadmissible, for it would be absurd to pretend that the primum 
movens of life is in melted caustic potash. Such is the way of 
obtaining a decisive result. In one word, I only ask Dr. Bastian 
to eliminate the bacteria germs which were contained in the aqueous 
solution of potash he employs. If Dr. Bastian finds it difficult, 
from the apparatus he uses, and does not describe, to bring the 
potash to a red heat previous to cooling it, and dropping it as a 
solid into the urine, let him, instead of heating it to 100° C, heat 
it to 110° C, and he will then find sterility if he operates with 
vigorous accuracy. If he still preserves his doubts, let him sup- 
press the preUminary condition of causing the urine to boil ; for it 
is a remarkable fact that urine in its absolutely normal state as it 
leaves the bladder of a healthy man remains sterile if a certain 
quantity of potash is dropped into it, with the precautions I have 
described, in chapter iii. of my recent work on beer, to avoid 
contact with atmospheric germs. Dr. Bastian conscientiously 
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