10 Geologys&ec. of the Connecticut. 
near the mouth of Miller’s river, it appears in one or two 
detached eminences of considerable height; directly west 
of which, only a few rods, is another hill of puddingstone 
similar to that of Toby. The granite can be traced nearly 
all the way through Northfield at a low level, and in 
the north of this town it seems to pass under the geest and 
higher rocks, and to appear again in Winchester and Ches- 
terfield, of greater width, and here it is beautifully porphy~ 
ritic. As we go north, therock exists iv distinct beds in mi- 
ca slate and gneiss, and also it appears at the tops of moun- 
tains sometimes forming conical hills almost naked. Wit- 
ness the west partof Surrey and Alstead. 9 9) 0 
The texture of this granite is coarse, in some. instances 
very coarse, the plates of mica being several inches across. 
Ie main colour is white. A beautiful. variety, however, 
rs in Leverett, in which the felspar, which is abundant, 
is is of alight blue; the quartz of a dark a Repeal to 
black; and the mica the usual light gray. Thisa rare va- 
riety, and a fragment of a crystal of this blue ps wee meas- 
ured in its longest direction 8 inches. 
his range of granite contains several veins of metals, 
such as galena, copper pyrites, blende and iron ; which will 
be more pertieularly described hereafter. 
this range exists in the form of beds and ruins: 
yet so far as I have examined it, it will not be easy to prove 
that the whole of ican be referred to this form. . Lam yet 
of opinion that along the central parts of the range may be 
seen emerging an original fundamental deposit of granite. 
hese are all the depositories of granite of considerable 
extent, which Ihave discovered in the region embraced 
the map. Granite existsin many other places along this 
river in beds and veins; but not of sufficient extent to claim 
to be represented on the map. It is possible, however, that 
what I call beds and veins, may not in all cases be such: 
For it is generally allowed, I believe, that the basis rock in 
all New-England is granite, and this nucleus, if I may so 
call it, is doubtless very uneven, having many. prominences 
and corresponding hollows. In some places, perhaps, sage 
projections have never been covered by other rocks, such 
for instance, as black Mountain. In other cases pv is 
every appearance to indicate that the higher rocks have 
beem worn away, and thus the granite has been disclosed: 
