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And firft, it is gratuitous, not only becaufe it is unnecfTary, 

 as we have already fliewn, but alfo becaufe it is inconfiftent 

 with our author's own theory. According to him thefe ftrata 

 which were contfolidated by heat were compofed of materials 

 gradually worn from a preceding continent, cafually and 

 fucceilively depofited in the fea ; where then will he find, and 

 how will he fuppofe, to have been formed thofe enormous 

 mafles of fulphur, coal, or bitumen neceffary to produce that 

 immenfe heat neceffary for the fuuon of thofe vaft mountains 

 of flone now exifting ? All the coal, fulphur, and bitumen, 

 now known, does not form the ---'--_ part of the materials 

 depofited within one quarter of a mile under the furface of 

 the earth; if therefore they were, as his hypothefis demands, 

 carried off and mixed with the other materials, and not formed 

 in vaft and feparate colledlions, they could never occafion, by 

 their combuftion, a heat capable of producing the fmalleft 

 effe(fl, much lefs thofe gigantic effedls which he requires. 

 Again, it is contrary to all we know of the aEliott of heat ; by this 

 we are informed that heat may be produced among hard bodies 

 by attrition, and in inflainmable bodies by combuftion. To 

 produce heat by attrition it is neceflkry that the bodies rubbed 

 together be fo hard as that their particles fliould not eafily 

 be abraded, and alfo that they be pcrfecflly dry ; if, therefore, 

 the ftrata formed in the bed of the ocean were loofe, porous, 

 and fpongy, previous to the produdlion of heat, and alfo inti- 

 mately penetrated with water, as our author repeatedly afferts, 

 it is evident, from all we at prefent know, that no degree of 

 attrition which they might endure could produce the fmalleft 



I 2 degree 



