156 EFFECTS of HEAT 
in the laft-mentioned experiment, whilft the fubftance of the 
contiguous ftrata retained a confiderable degree of firmnefs. In 
this ftate of things, the ftratum juft mentioned, would very na- 
turally become the fcene of a flip, occafioned by the unequal 
preflure of the furrounding maffes. By fuch a fliding motion, 
accompanied by great compreflion, a tree would be flattened, 
as any fubftance is ground in a mortar, by the combination of 
a lateral and direé& force. At the fame time, the fhells along 
with the trees, would be flattened, like thofe defcribed by BErc- 
MAN; while thofe of the fame fpecies in the neighbouring 
limeftone-rock, being protected by its inferior fufibility, would 
retain their natural fhape. 
TX. 
Application of the foregoing refults to Geology.—The fire employed in the: 
Huttonian Theory is a modification of that of the Volcanoes.—This mo- 
dification muft take place in a lava previous to its eruption.—An Inter- 
nal Lava is capable of melting Limeftone.—The effects of Volcanic Fire 
on fubftances in a fubterranean and fubmarine fituation, are the fame as 
thofe afcribed to Fire in the Huttonian Theory.—Our Strata were once 
in a fimilar fituation, and then underwent the action of fire.—All the 
conditions of the Huttonian Theory being thus combined, the formation 
of all Rocks may be accounted for in a fatisfactory manner.—Concli- 
Sion. 
Havine inveftigated, by means of the foregoing experi- 
ments, fome of the chemical fuppofitions. involved in the Hut- 
tonian Theory, and having endeavoured to affign a determi- 
nate limit to the power of the agents employed ; I fhall now 
apply thefe refults to Geology, and inquire how far the events 
fuppofed 
