IIo 
THE DEATH-POINT OF BACTERIA 
Description of 
Experiments. 
Results. 
Inferences. 
A. Boiled ammonic-tar- 
trate solution, inoculated 
with an unheated drop of a 
similar solution turbid with 
Bacteria, &c. 
B. Boiled ammonic-tar- 
trate solution, inoculated 
witha drop of a turbid saline 
solution previously heated 
to 140° F. 
C. Boiled turnip-and-hay- 
infusions, inoculated with a 
drop of a turbid saline solu- 
tion previously heated to 
140° F. 
D. Boiled turnip-and hay- 
infusions, inoculated with a 
drop of an unheated turbid 
saline solution, the inocu- 
lated fluid being  sub- 
sequently heated to 140° F. 
E. Boiled turnip-and hay- 
infusions, inoculated with a 
drop of an unheated saline 
solution, the inoculated fluid 
being subsequently heated 
to 140° F, 
Turbid in 40 hours. 
Clear at the expira- 
tion of Sth day. 
Turnip-infusions tur- 
bid in 2} days. 
Hay-infusions clear 
at expiration of 8th 
day. 
Turnip-infusions tur- 
bid in 24 days. 
Hay-infusions clear 
at expiration of 8th 
day. 
Turnip-infusions tur- 
bid in 28 hours. 
Hay-infusions turbid 
in 38 hours. 
That boiled ammonic-tar-° 
trate solution is a fluid 
inoculable by living Bac- 
teria, &c., and favourable 
for their growth and rapid | 
multiplication. 
That Bacteria, Vibriones, 
and their supposed germs 
are either killed or de- 
prived of all power of 
multiplication when heat- 
ed to 140° F. in this fluid. 
The precisely similar be- 
haviour of the turnip- 
and hay-infusions of 
series C and series D re- 
spectively shows that the 
Bacteria, Vibriones,and 
their supposed germs are 
as inoperative in series 
Das they are known to 
be in series C; whilst 
the behaviour of the hay- 
infusions shows that they 
are little amenable to the’ 
influence of the drop of 
the saline fluid when its 
living units are killed. 
Shows that the heat of 131° 
F. is not sufficient to kill 
Bacteria, Vibriones, and 
their supposed germs in 
organic infusions, and, 
again, that turnip-infu- 
sions are more rapidly in-. 
fluenced by such an inocu- 
lating agent than some 
hay-infusions.* 
No experiments could speak more decisively. Those 
of series B show that Bacteria, Vibriones, and their 
* These experiments of series C, D, and E were many times repeated 
with specimens of the same turnip- and hay-infusions, the specific gravity 
of the former being about 1008 and that of the latter 1005. 
Different 
Specimens [of the material to be infused, and] of hay especially, vary so 
much that it becomes absolutely essential to use portions of the same 
infusion for the comparative experiments of these different series. 
