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XXXII. ANALYSIS 
OF SULPHATE OF BARYTES, FROM HATFIELD, MASSACHUSETTS. 
By JOHN GORHAM, um... a.a.s. 
Adjunct Professor of Chemistry and Materia Medica in Harvard University. 
mee 
HAVING lately read in the New York Mineralogical Journal, 
an account of the chemical examination of heavy spar from New Jer- 
sey, by Mr. George Chilton, I could not avoid remarking the great 
resemblance in external characters between the substance above 
mentioned and the Sulphate of Barytes of Massachusetts. In order 
to ascertain whether they equally agree in chemical composition, 
the latter has been subjected to analysis, an abstract of which I haye 
the honour of presenting to the Academy, together with specimens, 
from a portion of which this analysis was made. 
This mineral is found i in great abundance in Hatfield in this state, 
also less pure and in smalier quantities at the lead 1 mine near North 
Hampton. Ihave beeninformed by Gen. Maltby, to whose politeness 
1am indebted for these specimens, that it is found in veins running 
through beds of gneiss or granite, and forming with the horizon an an- 
gle of 40° or 50°. These veins make their appearance at the surface 
of the ground, but are there very narrow ; but they rapidly increase 
in width as they descend, and at a short distance from the surface 
their diameter i is from 3 to 4 feet. Large quantities of it have been 
thrown up from a vein, opened for the purpose of obtaining lead and 
copper, of which there are some indications. | When pure it is ofa 
pure white, translucent and of a pearly or porcelain lustre. Some 
specimens are tinged with a reddish yellow colour, arising from the 
presence of oxide of i oe 
