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XXXIII. An Examination of various Ores in the Mufewn 
of Dr. William Hunter. By George Fordyce, M. D. 
F. R. S. and Mr. Stanefby Alchorne. 
Read May 20, 1779. 
TV /T INERS and aflay-mafters being generally em- 
^ “*■ ployed in finding out metals for profit, without 
inquiring into the ftate or combination they are in, have 
made ufe of procefies adapted, in many cafes, to invefti- 
gate the quantity of metal, guefling often at its ftate or 
combination; and fpecimens being procured from them 
for cabinets, an erroneous account has not only been 
given of their contents, but thefe errrors have alfo crept 
into books of natural hiftory : for this reafon Dr. fordyce 
determined to aflay many of the doubtful fpecimens, by 
procefies better adapted to find the ftate or combination 
of the metal than thofe commonly in ufe ; and procured 
the afliftance of his friend Mr. alchorne. The refult 
of fome of their inquiries they now lay before the So- 
ciety. 
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