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notwithftanding that the fpecific gravity of by far the greater part 

 of the ftones and earths it contains does not exceed and fcarcely 

 amounts even to three times the weight of an equal bulk of 

 water, and that the quantity of mineral fubftances whofe fpecific 

 weight exceeds four times that of water is alraoft infinitely fmall 

 in comparifon to the other known component parts of the globe, 

 and finally that the weight of moft iron ores is about four or 

 five times that of water ; all this I fay confidered, it is difficult 

 to avoid concluding that the interior part of the globe confifts 

 chiefly of iron ore difpofed in one or more aggregate maflTes; a con- 

 clufion that is farther confirmed, on refleding that volcanic lavas 

 ejected from the deepeft recefles with which we are acquainted 

 contain from 15 to 20 or 25 per cent, of iron in the ftate moft 

 favourable to magnetic attradion. 



Taking then this aflTertion to be as fully proved as its fubjed 

 matter is capable of being afcertained, we may deduce from it the 

 following corollaries : 



I ft. That as the ferruginous matter in the globe being by far 

 the moft copious, its univerfal attradive power is principally feated 

 in the ferruginous part. 



ad. That as all terraqueous matter was originally in a foft 

 ftate, its parts were at liberty to arrange themfelves according 

 to the laws of their mutual attradion, and in fad did coalefce and 



cryftalize 



