Glacial Lakes. — Upham. 22C> 
feet or more above the lake. In the west part of Albany such a 
lower delta forms a plain 200 to 225 feet above the sea, extend- 
ing westward from Washington park. Another is well devel- 
oped at the west side of lake Saratoga, which is 204 feet above 
the sea, the plain being at 270 to 280 feet, a few miles east from 
the delta of Saratoga Springs. A third is at Sandy Hill, on the 
Hudson, about two miles southeast of Glens Falls, having a 
hight of 290 to 300 feet above the sea, with an extent of two' 
miles from south to north and a width of one mile. 
Adjoining the last, and continuing to the south, east, and 
northeast, is a still lower delta, reaching from Fort Edward 
about eight miles northeast, with its margin mostly about a 
third of a mile west of the railroad and the Champlain canal. 
Its hight, which decreases northward, is about 100 to 75 feet 
above the canal, or 250 to 225 feet above the sea. The several 
levels of the deltas, from the highest, at Glens Falls, to these 
last noted, mark stages of the gradual elevation of the land 
and consequent lowering of the shore lines along the sides of 
the valley. 
The delta at Fort Edward and northeastward probably is 
referable to the glacial lake St. Lawrence, which would then 
have covered the low divide between the Hudson and lake 
Champlain on the route of this canal, 147 feet above the sea, 
and 50 feet above the lake. There is no evidence that any 
stream has flowed across the divide, which is a wide and nearly 
flat tract of the glacial and modified drift, only four miles dis- 
tant from the Hudson at Fort Edward. Wood creek flows 
thence north-northeasterly about twenty miles to the river-like 
southern end of lake Champlain at Whitehall. About ten miles 
from Fort Edward, the creek passes from the open valley of 
the Hudson into a very narrow defile inclosed by rock 'cliffs, 
with bold hills rising near at each side, and ascending north- 
westerly to the front range of the Adirondacks ; but the lower 
valley, approaching Whitehall, expands to a width of nearly a 
mile. 
After the ice-sheet blockade on the lower part of the St. 
Lawrence basin was melted through, the sea came in, as is 
known by its fossiliferous deposits, reaching to the south part 
of the basin of lake Champlain, to the Thousand Islands at the 
mouth of lake Ontario, and at least to Pembroke and Allumette 
