3d Geology, Sc. of the Connecticut. 
The greatest part of this greenstone is greenstone slate, 
the strata having the same direction as that at Milford, and 
being nearly perpendicular to the horizon, bearing a few de- 
grees one way or the other occasionally. This slate is alse 
more crystalline than the same rock at New-Haven. tis 
however al sh 
es it from hornblende slate, towards which it verges sand i into 
which it probably passes. Notwithstanding the very deci- 
dedly fissile character of this slate, | have noticed in some 
instances a tendency in it to the trappose form ; some of the 
specimens having a cleavage, like many crystalsy:i in two di- 
rections, one coinciding with the direction of the strata and 
the other. ranning across the strata. The proportion of oa 
spar. in this rock is small, often alm 
rite, however, abounds as in the greenstone slate of Milford; 
and often it becomes a ‘oblate slate. Seams and beds 
of quartz are common in the Whately rock and also granu- 
Jar epidote. 
ome of the rock colored, as hornblende slate in | Shel- 
burnes. wines me resembles certain 
i t Bt | avi* 
eee an 
aifleale to. pre its line Soeae rote — d, by some, 
this Whately rock would probably be denominated horn- 
blende slate: but I think there is a distinction between the 
two rocks; and so long as any of the stratified rocks of Mil- 
ford retain the name of greenstone slate, it would seem the 
_ Whately rock, from its resemblance and similar associations 
with unstratified primitive greenstone, demands the same ap- 
pellation, An observer will be struck with the resem- 
blance of the greenstone strata at these two places, and with 
their similar situation in regard to mica slate; and he will 
be disposed to enquire whether these rocks were not once 
continuous between these two places ;—and in the interme- 
diate space, he will find sufficient evidence in the great quan- 
tity of mingled detritus of other rocks, that the higher strata 
have suffered much from some levelling agent in former 
days. 
