394 The American Geologist. Juno, 1897 
of wave action was looked for on the exposed outer slope, at 
levels corresponding to the valley terraces, but none was 
found. Afterward I learned from credible sources that 
there are sandy terraces in the valley of the east fork of the 
Au Sable river near Keene, at levels which seem to correspond 
with those near Redford. 
The reconnoissance which we made was not a thorough one 
and the facts gathered are too few for positive statements. 
But it seems pretty clear that at least in the Saranac valley 
there was still water at the level of the Wilcox terraces, and later 
at that of the High falls and Dannemora terraces. The absence, 
so far as observed, of any evidence of wave action at these 
levels, even on the outer exposed slopes, suggests that this body 
of water was not of great size, but was confined to this valley 
and perhaps one or two other adjacent valleys separated by 
cols a little below the terrace level. Apparently the only ex- 
planation of such a lake is that it was held up by an ice-dam 
— by the great glacial tongue that extended southward in the 
valley of lake Champlain. It is not certain, but seems likely 
that at its greatest extent this lake included the valleys of 
both the east and west forks of the Au Sable river. This 
would give it a quite irregular shape with three expanded 
parts. For this lake I propose the name lake Adirondack. 
There was probably no other glacial lake of equal size within 
the Adirondack area. 
The outlet of lake Adirondack was not found, but the Wil- 
cox terraces are close up to the general tloor or half-tinislied 
])eneplain of the Adirondacks. Nearly all the modern lakes 
in the central area of the mountains lie in basins only slight- 
ly depressed below this plain, which is between 1,400 and 
1,600 feet in altitude, and the higher mountain peaks stand as 
monadnocks or clusters of monadnocks upon it. 
In one or two seasons after our joint excursions Prof. Spen- 
cer carried his explorations into the mountains of New Eng- 
land. He reported his results at the Springfield meeting of 
the American Association for the Advancement of Science in 
August, 1895, and claimed to have found evidences on both 
the north and the south sides of the mountain masses of New 
England that indicate post-glacial or glacial submergence to 
