^"ounlLfoct rffT PROCEEDINGS OF SOCIETIES. 223 
only be settled by a careful examination of the lowest and minutest 
forms of life. Now, it was well known that if an " infusion " of animal 
or vegetable matter were placed in, say a glass vessel, and left for 
some hours, it teemed with life in its lowest forms — molecules, bac- 
teria, vibrios, and even ciliated animalcula. Nor was an " infusion " 
necessary. Water taken from a shower of rain after drought was 
equally efficient. What, then, is the origin of these ? Do they result 
from some physical force, uniting the fortuitous particles in the water ? 
or are the ova of these living forms — immeasurably minute — floating 
in the air, deposited in the water, the element of their development 
and life ? To answer this question in a scientific way it was evi- 
dently essential that we should be absolutely certain that the water 
does not contain the germs of these vital forms. To say that they 
are not seen when the infusion is first made, is — even if the asser- 
tion be granted — only to suggest that your powers of research are 
not equal to this discovery. There must be, not assumption, but 
certainty. This might be done by producing the water syntheti- 
cally from its pure element. This the author carefully did by 
reducing the black oxide of copper with hydrogen, procuring about 
a wine-glass of water. This was divided into three parts. One 
part was placed in an exhausted flask, and the ingress of air pre- 
vented. Another third was placed in a U-shaped tube, and the 
open ends plugged with cotton wool, thus causing the air to be 
" wiped " in its passage to the water. The third part was freely ex- 
posed. In five days the exposed vessel teemed with bacteria and 
vibrios. In eight days the water in the plugged tubes was searched 
and was almost entirely void of life. In twelve days that in the flask 
was carefully examined with the y^g^-inch and ^L_inch objectives of 
Powell and Lealand, and absolutely nothing was discovered. This 
was repeated with the same results. But in this instance the flask, 
at first exhausted of air, was next supplied with air of which the 
elements (oxygen and nitrogen) had been carefully produced in 
the laboratory. But no life resulted. The same water was then 
freely exposed to the air, and in four days abundance of bacteria 
were found. Infusions of hay were then used : some vessels, con- 
taining portions of the same infusion, being exposed to an artificial 
atmosphere, others to the natural. Life was found in both alike, only 
apparently in greater abundance in the former. Hence, then, the 
ova did not come from the air alone, if at all. Therefore if the 
germinal forms existed they must have existed in the infusion. 
After a few remarks from the President, the meeting concluded 
with the usual conversazione. 
