ALLUVIAL DIVISION. 
81 
In Albany county, stalactites and stalagmites were observed in some parts of the caves in 
Bethlehem, near Clarksville. The stalagmites in some places formed thick masses, highly 
crystalline. Tufa was also observed near a copious limestone spring near Clarksville.* 
In Greene county, tufa was seen near a limestone spring three miles west of Athens ; also 
about three miles west of Coxsackie ; also about three miles west of New-Baltimore ; also 
at several localities by limestone springs along the base of the limestone cliff by the road-side, 
between Catskill and Saugerties.f 
In Washington county, tufa occurs near Whitehall, as a deposit from springs.t 
In Ulster county, tufa was observed on the banks of Stony creek, on the land of David 
Schoonmaker, about two miles south of Rochester, at the base of a cliff of the water lime¬ 
stone series. It contained helices and impressions of leaves. It was white and porous, and 
specimens of incrusted moss were observed. 
In Columbia county, tufa, enclosing helices and encrusting moss, occurs in several places 
around Becraft’s mountain; but it is more easily found at the spring that supplies the city of 
Hudson with water. 
The localities thus far mentioned, are all at or near the base of the Water-lime group of 
the Helderberg division of rocks. The waters that issue from this junction of the water lime¬ 
stones with the “ Salt group,” or with the rocks of the Hudson slate group, are all strongly 
impregnated with carbonate of lime, and in many places with several other mineral ingre¬ 
dients, giving rise to mineral springs. A large share of the sulphur springs of the First dis¬ 
trict have this geological situation. 
In Saratoga county, tufa was observed on the banks of the Hudson between Glen’s and 
Baker’s falls. The most beautifully incrusted moss was obtained from this locality. It is 
said to abound at Saratoga.^ 
In Schenectady county, tufaceous marl in a loose form was observed a few miles above the 
city of Schenectady, near the left bank of the Mohawk. Tufa is also said to occur near the 
city. II 
These localities in Saratoga and Schenectady counties, are near the Trenton limestone. 
Concreted carbonate of lime was seen in small quantity, at and near the “ Spook hole,” a 
cave near Barnegat in Dutchess county. Tufa is mentioned by Cleaveland (p. 175), near 
Rhinebeck. 
Tufaceous marl occurs on the farm of Mr. Tilden in New-Lebanon, Columbia county. It 
is deposited from the water of a limestone spring. The deposit is abundant, and may be 
used as a marl. 
Calcareous tufa is deposited in abundance from the thermal waters of the New-Lebanon 
springs. 
* Calcareous tufa is said to have been found at Albany, by Mr. J. Eiokts. (Webster’s Catalogue of the Minerals of New- 
York, 1824, p. 5; and Robinson’s Catalogue of Minerals, p. 114.) 
t Robinson’s Catalogue of Minerals, p. 116 - 120; and Silliman’s Journal Vol. 3, p. 236. 
t Robinson’s Catalogue of Minerals, p. 158. Prof. Wells. ^ Ib. p. 150. || Ib. p. 150. Prof. Silliman. 
Geol. 1st Dist. 11 
