Lead Mines, &c. of Hampshire County, Mass. 253 
ows: there 
hill; 6, c, d, the strata of mica slate, greenstone and mica- 
ceous limestone, in a vertical 
Ite: m, the vein of quartz 
branching off from the metallic 
which are several feet deep. The druses are studded with 
crystals, beautifully approaching to a green, owing appar- 
ently to the colouring matter of the greenstone having pen- 
etrated the quartz r 
By going west one half mile from the last mentioned vein, 
another is seen, marked 5 on the map. his is also in 
granite, on a moderate elevation, and seems to rise from un- 
der the mica slate, but in the course of five or six rods, it 
between the fingers ; it is in cavities in the gangue, some ©: 
which are twe or three inches in diameter, completely 
filled with the oxide. Several blocks of the gangue contain- 
ed black manganese, somewhat granular. Upon break- 
ing the manganese, jt had a metallic lustre, or at least it con- 
tained minute particles of a mineral scattered through it, 
of a steel gray, which I took to be iron; but it was insensi- 
ble to the magnet, Sometimes the manganese was attached 
to the outside of the blocks only, then again it filled cavities ; 
and in one instance, it appeared to be a kind of cement to 
hold two or three different blocks together. The width of 
this vein, where it is seen, is two or three feet. : 
Geest seems to cover all the rocks in the vicinity of this 
mine, to a considerable depth, and it is only where the vein 
. 
js seen that the granite and mica slate appear to rise above 
