REPORT OF THE DIRECTOR, 1922 169 
lowering ice surface in this basin is marked by sand-plains built 
over and against its thin edge by the Sacandaga river near North- 
ampton and by the high level kame-terraces west and southwest 
of Corinth (the latter mapped and described by Stoller).1° Both 
of these deposits are below the contour line of 1,000 feet. The 
southward outflow from the Sacandaga was not investigated. 
The waters of the Hudson coming from the Adirondacks car- 
ried considerable quantities of coarse detritus out over the ice at a 
level as much above the sagging kame belt above Corinth (elevations 
from 600 to goo feet) as the thickness of the ice margin onto which 
it was built. Much of this coarser material was not moved far 
and remained for the river to rehandle and sort over as the body 
of the ice shrank, but the finer sands at this level and lower levels 
were carried to great distances and covered parts of the stagnant 
glacier so effectually that they were not floated by the rising 
waters of Lake Albany, and remained partly unmelted even after 
this body of water had disappeared. In addition to the basins of 
Round and Saratoga lakes there are other evidences of buried ice 
which outlasted Lake Albany in the same district. Both the 
Hoosick river and the Batten Kill built deltas over stagnant ice 
occupying the Hudson gorge. The gradual melting of the block 
covered by the former gave rise to those stream terraces behind 
it which are not represented by corresponding terrace levels else- 
where in the vicinity. The delta still covers the gorge and forces 
the Hudson westward onto the higher floor of the valley. The 
delta of the Batten Kill also forced the Hudson into what has 
been called the Coveville channel as long as the ice block which 
it had covered remained unmelted. The melting of the buried 
ice permitted the river to again take its course through the gorge 
as in Preglacial time. (See Cohoes and Schuylerville quad- 
rangles.) The basin of Ballston lake has had no mysterious 
origin ; together with the basins of Otsego lake and a few smaller 
bodies of water, it represents, east of the Adirondacks, the same 
kind of glacial ploughing exhibited west of that barrier by the 
basins of the Finger and associated lakes. It is not a graben and 
is not of Postglacial origin. It could not have escaped being 
filled with sand if crossed by a river engaged in cutting away 
the section of sand plain which formerly filled the Mohawk valley 
* Glacial Geology of the Saratoga Quadrangle. N. Y. State Mus. Bul. 
183. 
