THE GEOLOGICAL HISTORY OF NEW YORK STATE 1 GAT 
first named valley only to make a very sharp turn back on its 
course to flow across the mountains and into the Hudson at 
Luzerne. A preglacial divide was located at Conklingville as 
shown by the gorge there; the perfectly graded condition of the 
valley bottom westward from that place; and the flaring of the 
valley westward. This remarkable deflection of the river was 
caused by the building of a morainic blockade across the southern 
end of the Paleozoic rock valley from Broadalbin to Gloversville. 
The peculiar courses of Hans and Kennyetto creeks are thus also 
easily explained. 
The Hudson river now flows through a gorge more than 1000 
feet deep just above Stony Creek station, and thence to the north 
end of the Paleozoic rock valley at Corinth where it turns abruptly 
to the northeast to flow across the Luzerne mountain ridge. The 
preglacial Hudson certainly did not flow through the Stony creek 
gorge, but rather, where the gorge now is, there was an important 
divide. Among other proofs for this former divide are: the deep, 
narrow gorge of recent origin; the flaring of the valley both north- 
ward and southward from the gorge; and the anomalous turns of 
both the Hudson and Schroon rivers toward the southwest through 
a highland region of hard rock, instead of southeastward across 
the much lower land between Warrensburg and Lake George. The 
most probable preglacial channel was past Warrensburg, Caldwell, 
and Glens Falls as shown on the map. The now extinct Luzerne 
river started on the Stony creek divide, and flowed southward past 
Corinth and thence through the Paleozoic rock valley to the west 
of Saratoga Springs. The cause of the passage of the Hudson over 
the Stony creek divide was partly due to a lowering of the divide 
by ice erosion, but mostly to the fact that during the ice retreat the 
ice lobe in the Lake George depression forced the Hudson river to 
take a more westerly course which was continued after the melting 
of the ice. The deflection of the river across the Luzerne mountain 
divide was certainly caused by heavy drift accumulations in the 
Paleozoic rock valley south of Corinth. 
The famous Ausable chasm in Clinton county is a fine illustra- 
tion of a deep, narrow gorge cut through the Potsdam sandstone 
by the Ausable river since the Ice age. The river was deflected 
from its preglacial channel by heavy drift filling. 
According to evidence recently presented by Fairchild, the lower 
portion of the Black river did not flow, as now, westward past 
Watertown and into the Ontario basin, but continued northward 
to northeastward into the St Lawrence valley and in perfect 
