GLACIAL POT-HOLES AT CROWN POINT, NEW YORK 461 
axis coincides with a joint-plane. The pot-hole shows four stages 
of grinding, each deeper than the preceding, excentric to it, and 
somewhat larger in diameter (Fig. 2). The first and shallowest 
is farthest to the north. This might indicate that during the first 
stages of its formation the ice mass was moving southward. Its 
greatest diameter is 7 feet 4 inches, and is found just below the 
second shoulder. Beyond this the deep cylindric bore is attained. 
The inside surface is very smooth in places, but in part is marked 
with a low relief of ridges due to differential erosion of the harder 
and softer portions of the rock (Fig. 3). The pot-hole, when dis- 
covered, was filled with its original content of glacial débris intact. 
Many wagon loads of this material, consisting of large bowlders 
smoothly rounded, smaller cobblestones, with a filling of gravel 
and sand, were removed and piled in a cairn near by. They are 
mostly crystalline rocks, and are of great variety, representing 
nearly all of the formations found in the region to the north. The 
large bowlder that lay in the apex of the hole, together with two 
beautifully rounded smaller ones that lay on either side of it, has 
been preserved. The largest is shown just inside the railing in 
Figs. 1 and 3. These stones were evidently the active tools of the 
glacial torrent at the time when grinding ceased and the hole became 
clogged with the mass of débris with which it was filled. The sur- 
face of the surrounding rock is planed smooth and is scored with 
glacial striae. 
Another glacial pot-hole occurs on Towner Hill, about six 
miles west from Lake Champlain, and about eight or ten miles 
southwest from the locality described above. This pot-hole was 
filled with ice when the photograph was taken, but it is said to be 
8 or 10 feet deep (Fig. 4). At the surface of the ice its diameter 
measured 5 feet by 4 feet 4 inches. Its original depth must have 
been considerably greater, because it has suffered erosion since its 
formation that has truncated it obliquely to its perpendicular 
axis. The rear wall rises 5 feet 6 inches above the surface of the 
ice that filled it to the lowest portion of the rim at the time it was 
seen (Fig. 4). It is located half-way down the face of a cliff of 
hard gneiss at an altitude of about 1,260 feet according to the U.S. 
Geological Survey sheet (Paradox Lake Quadrangle, N.Y.). The 
