A FORM OF OUTWASH DRIFT.^ 
A FRANK CARNEY. 
The triangular area indicated in fig. i encloses a formation of 
outwash drift in an association undescribed in the literature so 
far as the writer is aware. This drift forms a terrace in the grad- 
ual slope to the north, the decline being about 500 feet in three and 
one-half miles. Approaching the area along the highway from 
Bluff Point postoffice (v. Penn Yan quadrangle, N. Y.), one 
notes the closeness of rock to the surface and the general absence 
of glacial drift. The slope, though gradual, is presumably the 
resultant of stream work, being the south wall of an old valley, 
and of ice-corrasion; but the marked change as one nears this 
triangle is due to an unusual accumulation of drift which is some- 
what interlobate in origin; but the further differences between 
this and the typical outwash plain are so marked as to warrant 
a more definite description, and possibly a distinct designation. 
[topography of the region. 
The drift under consideration lies on the north slope of HalFs 
peninsula,^ designated on the Penn Yan quadrangle as Bluff 
Point, which attains an elevation of 700 feet above lake level. A 
nine-mile cross section, having a general east-west direction 
through the highest part of Bluff Point, resembles the letter “W, ’’ 
the inner legs being steepest but symmetrical to a vertical axis, 
while the left or west of the outer legs is the longer and has a gentler 
slope. The general relation of the two. arms of Lake Keuka is 
strikingly suggestive of an originally south-flowing stream, the 
valley of which has been blocked by a great mass of glacial drift 
southwest of Hammondsport, a village at the southern end of this 
body of water, thus giving rise to the lake, which now has an out- 
^ Reprinted from The American Journal of Science, vol. xxiii, May, 1907. 
^ James Hall, Geology of the Fourth District, Natural History of N. T., Part 
IV, p. 459> 1843. 
