Hupsox.—On Spontaneous Generation. 185 
Torula, Bacillus, and Miecrococci. It will be well now to examine briefly 
some typical experiments of the leading heterogenists—Pouchet, Jeffreys 
Wyman, and Bastian. 
Pouchet in one of his experiments introduces a flask into a vessel con- 
taining a decoction of barley which had been kept boiling for six hours; the 
flask being completely filled with this fluid was brought to the surface and 
corked, and then the circumference of the cork was surrounded by varnish. 
On the sixth day a deposit of yeast was seen, and the flask burst on the 
seventh. 
Here an impure vessel, cork etc., were used, and the heat was not 
applied to them for a sufficient length of time. Further, the fluid cannot 
have been boiling when the vessel was introduced and corked, otherwise, if 
he had done it efficiently, the operator would have sealded his fingers. It 
is, moreover, noteworthy that Pouchet only got organisms in one experi- 
ment of this kind. 
I may here say that Pasteur has completely upset all of Pouchet's 
experiments and deduetions. 
In Jeffreys Wyman's experiments such fluids as sugar gelatine and hay 
infusion, or flesh sugar and gelatine, were put into a flask, the neck of 
which was drawn out and bent at right 
angles, the extremity of the neck was in- 
serted into an iron tube and cemented 
there with plaster of Paris. The iron 
tube was filled with wires, leaving only 
very narrow passage-ways between them. 
The general relation between the quantity 
of fluid and the capacity of the flask was 
about 20 to 500. The flasks were then boiled for periods varying between 
a quarter and two hours, while at the same time the iron tube containing 
the wires was heated to redness. On withdrawing the lamp from the flask, 
the air which entered passed over these heated iron wires. When cold the 
flasks were sealed with the blowpipe. Fourteen vessels were prepared in 
this way, and in ten of these, when opened after the lapse of various periods 
of time, Vibriones and Bacteria were found. The other four remained barren. 
Curiously enough, Pasteur had made numerous experiments almost 
exactly similar and had obtained no organisms. Why this different result ? 
Pasteurs flasks were half filled with fluid, while Wyman's contained only 
from -p-s part, so that we can easily understand that in Wyman’s 
experiments a portion of the air and of the walls of the flask were never 
heated to within many degrees of the boiling point. Another source of 
fallacy is to be found in the fact that the air which passes through the iron 
tube with its contained wires is only exposed to dry heat, and it is within | 
