124 
GEOLOGY OF THE FIRST DISTRICT. 
being still flexible. The continuation of these beds of clay and sand to the lower part of 
Lake Champlain, abounds in fossils. They have been examined and described by Prof. 
Emmons, the Geologist of the Second District,* and are almost identical, it is said, with those 
now existing on our seacoast. Among them are a sanguinolaria, saxicava, modiola, mytilus, 
balanus, and some undetermined bones.f 
This formation has been deposited since the erosive action that has caused most of the 
scratches and smooth surfaces of the rocks, and it is believed to be very extensive in our 
country, though it has not been described, except locally, where it has been classed with the 
alluvial, drift, or tertiary deposits. Its general distribution in the valleys of the Hudson and 
Lake Champlain, and the islands at the southern extremity of this valley, have been already 
alluded to. Dr. Emmons has described the same in the valley of the St. Lawrence, and a 
similar formation exists around the lakes of the upper part of that valley, and is extensively 
distributed in Ohio, Pennsylvania, Michigan, and probably in both Upper and Lower Canada. 
The same formation, it is believed, as that of the Champlain and Hudson valley, is found in 
almost all the reenterings of the coast of New-England, and in the valleys of the principal 
streams, as the Connecticut, Thames,^ Housatonic, Pawcatuck, Blackstone, Charles, Mer- 
rimac, and along the coasts of Maine.§ It is also described in Delaware,|| and occurs exten¬ 
sively in the Middle and Southern States. It is not a very thick deposit, generally not 
exceeding one hundred feet; and on Lake Champlain, according to Prof. Emmons, it averages 
about twenty-five feet, and its upper level reaches two hundred feet above the lake, or two 
hundred and ninety-three feet above tide waterIn the valley of the Connecticut,'its thick¬ 
ness is supposed not to exceed one hundred to one hundred and fifty feet ;** and in the valley 
of the Thames and its tributaries, to be even less, generally not exceeding fifty feet.J In 
the valley of the Hudson, it attains a greater thickness than I have seen in other places, being 
in some instances more than two hundred feet, and attains an elevation of three hundred feet 
near the Hudson river, and perhaps still more above tide water towards the heads of the tribu¬ 
tary streams on the flanks of the main valley. 
* Geological Report of New-York, 1837, p. 120. 
t Idem, 1838, p. 236.—The following notice of fossils found at Brooklyn, is from the Albany Journal of June 10, 1842. If 
the description be correct, they are alluvial; and if the roots and peat be much below the level of tide water, would be an evi¬ 
dence of subsidence. I have not seen the locality, and the roots and peat may have been covered to that depth by the wash from 
the hills, or in filling marshes in grading for streets, making docks, etc. 
“ Fossils. We are told that in the excavations now making in the Atlantic dock at South-Brooklyn, at the depth of twenty 
feet, a good many roots of trees have been found, evidently in the position in which they grew ; and still lower down, a bed of 
peat.” 
X Mather on the Geology of Windham and New-London counties. Conn., 1834, p. 31. 
^ Hayden’s Geological Essays: Cleaveland, pp. 67, 105; Jackson’s Geol. Report, 1838, p. 95; Ib. 1837, p. 19. 
II Booth on the Geology of Delaware, 1841, pp. 94, 106. 
^ Emmons. Geological Report of New-York, 1838, pp. 233, 234. 
'** Stated to exceed one hundred feet: Silliman’s Journal, Vol. 9, p. 29. 
