84 THE DEATH-POINT OF 
doubt more effectually, and also of refuting the 
unwarrantable conclusion* of M. Pasteur, to the 
effect that the germs of Bacteria and Vibriones 
are not killed in neutral or slightly alkaline fluids 
at a temperature of 212°F., I almost immediately 
after the reading of my last communication com- 
menced a fresh series of experiments. 
Nearly two years ago, in my ‘Modes of Origin 
of Lowest Organisms, I brought forward evidence 
to show that Bacteria, Vibriones, and their sup- 
posed germs are killed at a temperature of 140° F. 
(60°C.) in neutral or very faintly acid solutions 
containing ammonic tartrate and sodic phosphate, 
and also evidence tending to show that these living 
units were killed in neutral infusions of hay and 
in acid infusions of turnip at the same temperature. 
The crucial evidence adduced concerning the 
degree of heat destructive to Bacteria, Vibriones, 
and their germs, in the saline solution, was of this 
nature. The solution had been shown to be incapable 
of engendering Bacteria and Vibriones (under all 
ordinary conditions) after it had been boiled, although 
it still continued capable of supporting the life and 
* Reasons for this opinion have been fully set forth in ‘‘The Begin- 
nings of Life,” vol. i., pp. 374 é seg. ; or the discriminating reader may 
at once find my justification for this expression by reading pp. 58—66, 
of M. Pasteur’s memoir in ‘‘ Anr.. de Chim. et de Physique,” 1862, 
