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at the same time displays all the characters of the jaspis sanguinaris, 

 or blood-stone. Jasper, indeed, manifests so frequently the indu- 

 bitable traces of wood, as to give room to believe that its origin 

 has been derived much more often from vegetable composition, than 

 has ever been supposed. It has often occurred to me to notice, in 

 a specimen of polished jasper, appearances which, though striking, 

 conveyed no idea of vegetable remains ; but which obviously did 

 so, after the judgment had been aided by the examination of ano- 

 ther specimen, which at the same time that it possessed the same 

 general features, and characters, of the former specimen, manifested 

 more plainly the marks of vegetable origin. Specimens of jasper, 

 which excite no suspicion of their dependence on vegetable decom- 

 position, in the minds of those unused to such inquiries: but which 

 display indubitably such an origin, to those who have been in the 

 habit of examining specimens of fossil wood, are very frequent ; so 

 frequent, indeed; and so strongly do I find that observation extends 

 the right of their claim Jo such an origin, that I can hardly help 

 concluding, that many of the jaspers owe something in their com- 

 position, to changed vegetable matter. 



Yours, &c- 



