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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 in- 
dubitable 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 another 
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 dependance on vegetable decomposition, 
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 j so frequent, 
indeed, and so strongly do I find that observation extends the right 
of their claim to such an origin, that I can hardly help concluding, 
that many of the jaspers owe something in their composition, to 
changed vegetable matter. 
Yours, &c. 
