THEORY of the EAR%H. 267 



from whence has come the metal into his vein ? Not from the 

 earth or air above, not from the flrata which the vein traverfes ; 

 thefe do not contain one atom of the minerals now cotifidered : 

 There is but one place from whence thefe minerals may have 

 come ; this is, the bowels of the earth, the place of power and 

 expanfion, the place from whence muft have proceeded that in- 

 tenfe heat by which loofe materials have been confolidated into 

 rocks, as well as that enormous force by which the regular flra- 

 ta have been broken and difplaced. 



OUR attention is here peculiarly called upon, where we have 

 the opportunity of examining thofe mineral bodies, which have 

 immediately proceeded from the unknown region, that place 

 of power and energy which we want to explore ; for, if fuch 

 is the fytlem of the earth, that materials are firfl depofited at 

 the bottom of the ocean, there to be prepared in a certain man- 

 ner, in order to acquire folidity, and then to be elevated into 

 the proper place of land, thefe mineral veins, which contain 

 matter abfolutely foreign to the furface of the earth, afford the 

 mod authentic information with regard to the operations which 

 we want to underftand. It is thefe veins which we are to con- 

 fider as, in fome meafure, the continuation of that mineral re- 

 gion, which lies necefTarily out of all poffible reach of our ex- 

 amination. It is, therefore, peculiarly interefling to know the 

 flate in which things are to be found in this place, which may 

 be confidered as intermediate between the folid land, upon the 

 one hand, and the unknown regions of the earth, upon the 

 other. 



WE are now to examine thofe mineral veins ; and thefe "may 

 be confidered, firfl, in relation to their form, independent of 

 their fubftance or particular contents ; and, fecondly, in relation 

 to the contained bodies, independent of their form. 



IN examining confolidated flrata, we remarked veins and 

 cutters as a proof of the means by which thofe bodies had been 

 confolidated. In that cafe, the formation of thefe veins is 



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