274 
BASALTIC ROCKS. 
commences at West Rock, near New-Haven, and 
extends from thence almost in a direct line to 
Mount Tom, near Northampton, in Massachusetts. 
From hence it stretches north through the Connec- 
ticut Valley, in connexion with the red sandstone, 
and so on into Vermont and New-Hampshire, asso- 
ciated with argillaceous and mica slate. We also 
meet with ridges and beds of greenstone in other 
parts of Connecticut, and particularly east of the 
main ridge already described. The greenstone in 
the eastern part of Massachusetts is of a dark green 
colour, from the presence of epidote, while that in 
the Connecticut Valley exhibits a gray or iron-rust 
colour, from the presence of oxide of iron. It 
seems to be a fine-grained mixture of hornblende 
and feldspar ; sometimes columnar^ frequently amyg- 
daloidal* and amorphous.] The scenery of the Con- 
necticut Valley derives its boldness, wildness, and 
beauty principally from the greenstone ridges that 
liave been described. The Palisades, or Cloister 
Mountain, on the Hudson, near New-York, are ba- 
saltic greenstone : and, as we go west, we strike it 
again at Patterson, where it forms the Falls of the 
Passaic, and the First and Second Mountains ; and, 
a little farther west, Freakness Ridge. A few miles 
south, and midway between the Hudson and the 
Delaware, we find it forming a considerable eleva- 
tion near Somerville, called the Somerville Trap 
Ridge. A section of the state still farther south, 
striking through Trenton, presents several ridges 
of greenstone or trap formation, as at Goat Hill, 
Belle Mount, Smith's Hill, &c. ; there being, in fact, 
a double or triple chain of trap hills extending north 
and south near the centre of the state, commen- 
* From " amygdala,^^ an almond. Any rock containing glob- 
ular masses scattered through it, like almonds in a cake, is said 
to be amygdaloidal. 
t From " a," without, and " morphe;' form : destitute of reg- 
ular form. 
