76 EFFECTS of HEAT™ 
the immenfity of the natural agents, whofe operations he fup- 
pofed to lie far beyond the reach of our imitation; and he 
feemed to imagine, that any fuch attempt muft undoubtedly 
fail, and thus throw difcredit on opinions already fufficiently 
eftablifhed, as he conceived, on other principles. I was far, 
however, from being convinced by thefe arguments ; for, with- 
out being able to prove that any artificial compreflion to which 
we could expofe the carbonate, would effectually prevent its 
calcination in our fires, I maintained, that we had as little 
proof of the contrary, and that the application of a moderate 
force might poflibly perform all that was hypothetically, af- 
fumed in the Huttonian Theory. On the other hand, I con- 
fidered myfelf as bound, in prattice, to pay deference to his 
opinion, in a field which he had already fo nobly occupied, 
and abftained, during the remainder of his life, from the pro- 
fecution of fome experiments with compreflion, which I had: 
begun in 1790. 
Ln 1798, I refumed the fubject with eagernefs, being ftill of 
opinion, that the chemical law which forms the bafis of the 
Huttonian Theory, ought, in the firft place, to be inveftigated. 
experimentally ; all my fubfequent refleftions and obferva-. 
tions having tended to confirm my idea of the importance 
of this purfuit, without in any degree rendering me more ap- 
prehenfive as to the refult. 
In the arrangement of the following paper, I fhall firft con- 
fine myfelf to the inveftigation of the chemical effects of Heat 
and Compreflion, referving to the concluding part, the appli- 
cation of my refults to Geology. I thall, then, appeal to the 
volcanoes, and fhall endeavour to vindicate the laws of ac- 
tion aflumed in the Huttonian Theory, by fhewing, that lavas, 
previous to their eruptions, are fubjec&t to fimilar laws; and 
that the volcanoes, by their fubterranean and fubmarine exer- 
tions, 
