Distillation of Ardent Spirit. 263 
charine matter can be fermented, and the indefati- 
gable Lavoisier has proved, “that sugar is a true 
vegetable oxyd with two bases, composed of hydro- 
gen and carbon, brought to the state of an oxyd by 
means of a certain portion of oxygen. Fermentation 
is the mere separation of its elements into two por- 
tions, in which one part is oxygenated at the ex- 
pence of the other so as to form carbonic acid; 
whilst the other part is disoxygenated in favour of 
the former, and is converted into the combustible 
substance called alcohol.” 
It was from a consideration of these circum- 
stances, that I was induced to try what effect an at- 
mosphere of some factitious airs would have on 
fermentation. « 
My experiments on this part of the subject have 
been confined to hydrogen, oxygen, and a mixture 
of the two. The hydrogen gas was made by de- 
composing water on iron-filings by heat, not by 
the sulphuric acid; and the oxygen gas was obtained 
from the oxyd of manganese. The processes 
were conducted in the following manner. I took 
three bottles similar to that represented in PI. [V, 
fig. 1. into each of which was put thirteen quarts 
of ‘wort of forty-five degrees of density, To 
each bottle was added four ounces of yest. “Af. 
ter the fermentation had begun I fixed a bag, 
containing one of the gases, in the stopper of 
each vessel, by means of a stop-cock and screw, 
