Thomson's theory of combustion.

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SECT. II.

THOMSON’S

THEORY OF COMBUSTION.

T HOUGH the preceding theory of combustion is simpleand beautiful, it appears from what we are now going to state,to be by no means satisfactory.

It has misled chemists by confining the term combustion tothe act of oxigenation, and considering that all bodies, duringtheir combustion, combine with oxigen, without at the same timerecollecting, that this latter effect may take place without any ofthe phenomena usually attendant on combustion; and that,though certainly all combustion pre-supposes the combination ofoxigen with a base, yet this combination may be, and repeatedly iseffected where no combustion can possibly take place. Nothingcan be more evident than the difference which in numberlessinstances prevails between the act of oxigenation in bodies, andthat of combustion, in as much as neither the phenomena at-tending on, nor the results arising from them are the same. Thata distinction therefore should be made between these processesis obvious ; and it is on this account that Dr. Thomson has of-fered a theory which considers this subject in a new point ofview, and which bids fair to enable us to estimate the pheno-mena of combustion much better than has hitherto been done.

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