292 W. J. Miller — Ice Movement and Erosion. 



The strise described above and plotted on the map (fig. 1) 

 indicate that in the northern part of the region here discussed 

 the southeasterly movement changed to the more nearly easterly 

 movement farther south, and this is just what would be 

 expected according to the statement of Chamberlin. It should 

 be noted that the Black river and upper Mohawk valleys, 

 which are the chief topographic features of the district, had 

 much to do with determining the direction of the flow of the 

 ice. Both of these valleys existed in preglacial times and the 

 close parallelism between the directions of the striae and the 

 directions of the valleys shows the influence of the latter in 

 determining the ice movement. 



There is other evidence, derived from the distribution of the 

 drift, to show the general southeasterly ice movement in the 

 region. Thus, within the Remsen quadrangle north of Hinck- 

 ley, fragments of Utica shale and Lorraine sandstone may be 

 found at least five or six miles east of the nearest parent ledges. 

 This strongly suggests a southeasterly current of ice. Also 

 the presence of marginal morainic materials and delta deposits 

 extending many miles along the southwestern Adirondacks 

 show that a border ice mass existed there during the time of 

 melting. Along the northwestern border of the Adirondacks 

 the ice undoubtedly moved southwestwardly. The writer has 

 seen magnificent displays of glacial grooves and strise bearing 

 southwestwardly, especially near Clayton. Along the eastern 

 border of the Adirondacks, the general southerly movement 

 of the ice has been well established, as has also the westerly 

 movement up the Mohawk valley towards Little Falls. Thus 

 the statement of Chamberlin, regarding ice flow around the 

 Adirondacks, harmonizes almost perfectly with observed strise. 



But the question still arises, what was the direction of the 

 current during the height of glaciation ? We have abundant 

 evidence to prove that this main current was a southwesterly 

 one. The Long Lake quadrangle is located in the midst of 

 the Adirondacks and upon the geological map of that area 

 Prof. Cushing* has recorded a number of striae, all of which 

 point toward the southwest. Over the region south of the 

 Adirondacks and the Mohawk valley the numerous observa- 

 tions of both Brighamf and Chamberlin;}; show that the ice 

 moved in a general southwesterly direction. Along the south- 

 western Adirondacks the writer has seen a number of good 

 examples of roches moutonnees, all of which bear southwest- 

 wardly. Among these one forms a narrow ridge about two 

 miles long which crosses Moose river above Fowlersville (Port 



*N. Y. State Museum, Bull. 115, p. 495, 1906. 



\ This Journal, vol. xlix, p. 216, 1895. % Op. cit., p. 365. 



