d thorough consideration of another
subject, more important if possible than the foregoing one, but like
it somewhat difficult to seize by reason of the very opulence of the
phraseology, logical and rhetorical, in which it has been set forth.
The subject now to be considered relates to what has been called 'the
death-point of bacteria.' Those who happen to be acquainted with the
modern English literature of the question will remember how challenge
after challenge has been issued to panspermatists in general, and to
one or two home workers in particular, to come to close quarters on
this cardinal point. It is obviously the stronghold of the English
heterogenist. 'Water,' he says, `is boiling merrily over a fire when
some luckless person upsets the vessel so that the heated fluid
exercises its scathing influence upon an uncovered portion of the
body-hand, arm, or face. Here, at all events, there is no room for
doubt. Boiling water unquestionably exercises a most pernicious and
rapidly destructive effect upon the living matter of which we are
composed.' [Footnote: Bastian, 'Evolution,' p. 133.] And lest it
should be supposed that it is the high organisation which, in this
case, renders the body susceptible to heat, he refers to the action of
boiling water on the hen's egg to dissipate the notion. 'The
conclusion,' he says, 'would seem to force itself upon us that there
is something intrinsically deleterious in the action of boiling water
upon living matter-whether this matter be of high or of low
organisation.' [Footnote: Bastian, 'Evolution,' p. 135.] Again, at
another place: 'It has been shown that the briefest exposure to the
influence of boiling water is destructive of all living matter.'
[Footnote: Ibid. p. 46]

The experiments already recorded plainly show that there is a marked
difference between the dry bacterial matter of the air, and the wet,
soft, and active bacteria of putrefying organic liquids. The one can
be luxuriantly bred in the saline solution, the others refuse to be
born there, while both of them are copiously developed in a sterilised
turnip infusion. Inferences, as we have already seen, founded on the
deportment of the one liquid cannot with the warrant of scientific
logic be extended to the other. But this is exactly what the
heterogenist has done, thus repeating as regards the death-point of
bacteria the error into which he fell concerning the germs of the air.
Let us boil our muddy mineral sol