118 THE DEATH-POINT OF BACTERIA 
distinct groups, though of course any such divisions 
as I am now about to sketch are purely artificial and 
are connected with one another in nature by innumer- 
able transitions, 
Nature of Fluids. 
A. Turnip-infusion with cheese, 
turnip - infusion neutralized by 
liquor potasse, ordinary turnip- 
infusion, strong hay-infusion, &c. 
B. Turnip-infusion neutralized 
by liquor potassze, ordinary turnip- 
infusion, ordinary hay-infusion, 
&e, 
C. Beer-wort,* &c. 
D. Weak hay-infusions, urine, 
solutions containing ammonic car- 
bonate and sodic phosphate with 
minute organic impurities, &c. 
Nature of Results. 
Within two to four days marked 
turbidity, owing to the appear- 
ance of swarms of Bacteria and 
Vibriones. Fluids more or less 
foetid. (Putrefaction.) 
No uniform turbidity, but growth 
of flocculi in a more or less clear 
liquid. After a time the flocculi 
(composed of aggregated Bac- 
teria and Vibriones) gradually 
subside, and the activity of the 
process ceases. Fluids either 
foetid or having a mere sour 
odour. 
Fluids which become more or less 
‘uniformly and rapidly turbid, 
owing to the appearance of 
swarms of Zorula, 
Do not become visibly turbid or 
produce visible flocculi, although 
on microscopical examination 
they may be found to contain 
living Bacteria pretty uniformly 
distributed, but in comparatively 
small quantities. The odour is 
often not more appreciably 
altered than the clearness of such 
solutions. 
* Ihave had no experience with such a fluid myself. M. Pouchet’s 
observations were, however, most striking on this subject (see his ‘‘ Nou- 
velles Expériences,” Paris, 1864, p. 190). 
