5?2 FRAGMENTS OF SCIENCE. 
in such things, and apparently also as regards a large 
portion of the medical profession, our clever countryman 
succeeded in restoring the subject to a state of uncertainty 
similar to that which followed the publication of Pouchet's 
volume in 1859. 
It is desirable that this uncertainty should be removed 
from all minds, and doubly desirable on practical grounds 
that it should be removed from the minds of medical men. 
In the present article, therefore, I propose discussing this 
question face to face with some eminent and fair-minded 
member of the medical profession who, as regards 
spontaneous generation, entertains views adverse to mine. 
Such a one it would be easy to name; but it is perhaps better 
to rest in the impersonal. I shall therefore simply call 
my proposed co-inquirer my friend. With him at my 
side, I shall endeavor, to the best of my ability, so to con- 
duct this discussion that he who runs may read and that 
he who reads may understand. 
Let us begin at the beginning. I ask my friend to step 
into the laboratory of the Eoyal Institution, where I place 
before him a basin of thin turnip slices barely covered 
with distilled water kept at a temperature of 130 degrees 
Fahr. After digesting the turnip for 
four or five hours we pour off the 
liquid, boil it, filter it, and obtain an 
infusion as clear as filtered drinking 
water. We cool the infusion, test its 
specific gravity, and find it to be ]OOG 
or higher water being 1000. A 
number of small clean empty flasks, 
of the shape shown on the margin, 
are .before us. One of them is 
slightly warmed with a spirit-lamp, 
and its open end is then dipped into 
turnip the infusion. The warmed 
glass is afterward chilled, the air within the flasks cools, 
contracts, and is followed in its contraction by the infusion. 
Thus we get a small quantity of liquid into the flask. 
We now heat this liquid carefully. Steam is produced, 
which issues from the open neck, carrying the air of the 
flask along with it. After a few geconds y ebullition, the 
open neck is again plunged into the infusion. The steam 
within the flask condenses, the liquid enters to supply its 
