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by a peculiar species of fermentation. The change, to which I allude, 
is one which takes place in the product of the vinous fermentation ; 
and which seems to point out a strong analogy between that species 
of fermentation and the process of bituminization. 
In the vinous fermentation, during the stage of sensible effer- 
vescence, as has been already observed, a considerable quantity of 
oxygen is dissipated, in a gaseous form, in combination with a 
portion of carbon, sufficient to form with it carbonic acid gas : this 
escape of these two principles, leaving, we may suppose, an in- 
creased proportion of hydrogen in the remaining mixture. In the 
next stage of the process, that which is accomplished in the closed 
vessels, part of the remaining oxygen, which is denied the oppor- 
tunity of thus liberating itself, with carbon, in a gaseous form, enters 
into another kind of combination with the same principle, and 
forms the acid of the wine ; which, according to the opinion of Four- 
croy, is the malic acid : whilst the hydrogen, uniting with another 
part of the oxygen, and holding a portion of carbon in solution, 
forms with it the spirituous or intoxicating part ; the whole forming 
WINE. This vinous fluid being subjected to the distillatory process, 
a new arrangement of these principles ensues : and a combination of 
them, in which hydrogen is highly predominant, comes over in the 
form of ALCOHOL. 
If to this alcohol an acid, but particularly the sulphuric, be 
added, then a substance will be separated, by distillation, the most 
light and inflammable of all fluids, termed ether ; and which, in 
consequence of its possessing these properties of the purest fluid 
bitumen, is often described by the same name, naphtha. But if 
the distillation be continued beyond this, a heavier and less volatile 
fluid comes over, containing a larger dose of carbon ; and is called, 
from its oily appearance, the oil of wine ; a gas being also at the 
same time separated, which, on being mixed with the oxygenized 
muriatic acid gas, actually produces an oil possessing peculiar pro- 
