46 EVOLUTION AND THE 
Secondly, the fact, which he discredited, of the ap- 
pearance of Bacteria in closed flasks after the boiling 
of their contents, has been fully substantiated by 
' Professor Sanderson, Professor Huizinga, and others. 
They have satisfied themselves as to the correctness 
of my statements, and have found that swarms of 
Bacteria will appear in the course of a few days 
within sealed experimental flasks whose fluids have 
been previously boiled. Meanwhile it has been shown, 
and is believed by the majority of biologists, that the 
briefest exposure to the influence of boiling water 
(212° F.) is destructive to all living matter. Whilst 
_ those who have attempted accurately to define the 
precise degree of heat which suffices to kill the 
lower infusorial organisms have invariably found 
that none of them could survive exposure to a tem- 
perature of 140° F. for five minutes.* Indeed all 
the simplest forms which can be individually watched 
are found to be killed when suddenly exposed to 
temperatures below 131° F., and Max Schultze} as 
well as Kiihne has ascertained that many of them 
perish even at or below 122° F. 
Thus it has been established that living protoplasm 
is certainly destroyed by sudden exposure to a tem- 
perature of 140° F. when in the moist state, irre- 
* Proceedings of Royal Society, No. 145 (1873), pp. 325—33I. 
+ Das Protoplasma, 1863, p. 63.. 
