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r 
and new substances are formed, differing much in their physical, as 
well as their chemical properties, from the substance from which 
they have proceeded. One particular point in which they almost 
always differ may be here very properly noticed. The combina- 
tions resulting from these spontaneous changes, occasioned by the 
intestine motions of the constituent principles, regularly produce 
substances less compounded than those which these principles pre- 
viously formed. Before the final change, however, is completed, 
certain regular periods in the process must be passed through ; and 
the substance exposed to the operation must necessarily exist in 
several intermediate states. In passing through these different states 
it acquires new and peculiar characters ; and may be arrested in any 
one of these stages of transformation, and so fixed, that it shall pass 
on to no further change. 
Between the phenomena of fermentation in general, and those 
which accompany that which I term the bituminous fermentation, 
I trust you will perceive a total agreement, when the latter are 
more particularly examined. But that this may more clearly appear, 
I will proceed to take a more particular view of the effects of this 
process, and compare them with those proceeding from the other 
species of vegetable fermentation. 
Vegetable matter, then, I consider as subject to five different 
species of fermentation, each of which appears to be, in a great 
measure, dependent on the degree to which the access of air and 
water is admitted. 
The saccharine fermentation takes place in those parts of vege- 
tables in which the saccharine principle seems to be present, and 
merely to require evolution, as in the roots of the parsnip, beet, &c. 
the monocotyledon seeds, &c. This principle acquires a saccharine 
form merely by the attraction of oxygen from the atmosphere, 
during the germination of these seeds; in which state it is pre- 
served by the common operation of malting. From other parts of 
