202 Geology, Mineralogy, Scenery, &e. 
subject of geology, on the part of readers who might be re- 
pelled by a severer method. 
August 26 1817.—On a very fine morning, with an ex- 
excellent travelling map of the State, and with the necessa- 
ry instruments, I commenced my tour in a gig. 
Upon the map (which was so folded as to lie constantly 
open at the desired place) I wrote down with a pencil, the 
“names of the strata at the moment of their occurrence, stop- 
ping frequently to break the rocks and to obtain specimens. 
West-Rock, Secondary Greenstone Ranges, &c. 
My course was nearly northwest on the great Litchfield 
road. From New-Haven to West-Rock, two miles, the 
country is alluvial, flat, sandy or gravelly. 
At West-Rock, which is a fine precipice of greenstone, 
reposing on sandstone, we enter a beautiful and very nar- 
row valley stretching to a great distance nearly North and — 
South. On the right are the bold ranges of secondary 
greenstone, about 400 feet high, with their rude perpendic- 
ular precipices, which (except at the South end of West- 
Rock where they terminate, and where the cliffs have been 
in some measure torn down and defaced to afford building 
stone for New-Haven,) present a time-worn aspect ;—and by 
the immense masses of broken rocks, which have accumu- 
lated at their feet, and slope half or two thirds of the way up 
their sides, evince that ages have passed since their cliffs 
were first exposed to the weather, and to the destroying in- 
fluences of time. As we go North, the cliffs become less dis- 
tinct, although probably not less elevated—but they are 
partially obscured by arable ground ; fields begin to slope 
up their sides, and cultivation appears, instead of the vene- 
rable ruins which abound farther South; still farther North, 
the cliffs appear only here and there, and finally at a dis- 
tance these hills assume a much more gentle outline, and 
appear in some measure to lose the peculiarities of aspect 
which characterise greenstone mountains. 
The valley at their feet is fertile, abounding with green 
meadows ; arivulet flows through its length and becomes 
the West-river, which empties into New-Haven harbour.— 
This valley is alluvial, although, in all probability, its foun- 
