280 
GEOLOGY OF THE FIRST DISTRICT. 
is five hnndred and thirty-nine feet.* From Tappan slote, near the New-Jersey line, the 
height of the trappean hills is less across Orangetown and the southern part of Clarkstown to 
two miles north of Nyack, where it sweeps around to the northeast to the Hudson, at the 
north end of Tappan bay ; and it forms a bold mural escarpment on the shore at Verdrietige 
hook, the southern knob of which is six hundred and sixty-eight feet, and the north peak 
is six hundred and forty feet above tide water of the Hudson. The Verdrietige-hook range 
sweeps then around to the northwest, along the shore of Haverstraw bay, to within about 
two miles of Haverstraw, where a deep valley, called the Long clove, presents a passage for 
a road between that and the high peak called the High Torn, the highest point of the range. 
This is elevated eight hundred and fifty feet, according to Capt. Partridge’s measurement.! 
From the High Torn, the range is very broken in its outline, consisting of very craggy masses 
of the trappean rock, but all connected, sweeping west in its general trend to the Little Torn, 
and thence southwest until it nearly unites with the Highland range of mountains. From the 
High Torn, the general height of the summits continually diminishes to the west and south¬ 
west, until it becomes merged in and below the red sandstone level, along the base of the 
Highlands, two or three miles southwest of Laden’s, called Ladenton on the map-! Be¬ 
tween Long clove and the High Torn, is another valley, through which a road is made. It 
is called the Short clove. 
Rockland lake, a beautiful sheet of water, is situated half a mile west of the Hudson, and 
south of the Long clove. The Verdrietige-hook range of trap rock intervenes between it 
and the Hudson, and the lake is skirted on its northeast shore by that rock. The ridge of 
trap between the lake and Hudson river, is six hundred and forty feet above tide water. 
The lake is one hundred and fifty feet above the level of the Hudson river, “ No stream of 
magnitude is seen to enter the lake, but it is the source of one of the most considerable 
branches of the Hackensack. Fed from below by mountain springs, it retains a greater uni¬ 
formity of temperature than is observed in ponds formed by the expansion of a river in a 
valley, and remains unfrozen after the North river is closed; this must be attributed to its 
great depth, and the warmth of its auxiliary streams” (springs), § 
“ The waters of the lake are soft and pure ; and as they repose on a sandy bottom, no 
water weeds or swamps are seen on its borders, except at the river’s outlet. The adjacent 
inhabitants are not subject to the fevers and early fogs of autumn; the waters of the lake re¬ 
maining colder than the air, morning exhalations do not arise to be condensed. The elevation 
* The following intennediate heights are taken from the geological section of the Hudson, by Mr Ackerly, which I copied many 
years ago. I regret that 1 have not the book, that I might draw from his observations, and give him credit for his labors. 
1. Fort Lee,. 311 4. Bluff north of 3 
2. Lydioher’s bluff,. 378 5. Pompey’s hook,. 
3. Bluff opposite Spuytenduyvel creek. 407 6. Bluff north of 5 
+ Pierce on the Geology of New-York and New-Jersey. (American Journal of Science, Vol. 2, p. 186.) 
t Burr’s County Map. 
4 Pierce on the Geology of New-York and New-Jersey. (American Journal of Science, Vol. 2, p. 187.) 
479 
517 
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