224 J. W. SPEXCER— POSTGLACIAL EARTH-MOVEMENTS 



parallel to the "height of land" for 60 miles, before turning southward 

 to Lake Saint John. 



The deformation extending to the "height of land" is further shown 

 by the Montreal River, flowing 60 miles northward, before being turned 

 abruptly southward (Bell). t 



By referring to the map, it is seen that the axis of the Laurentian 

 Mountain plateau, after trending southwestward from Labrador, turns 

 abruptly westward, and farther on again bends to the northeastward. 

 Thus the region of the greatest deformation coincides with the most 

 southern lobe of the Laurentian plateau. 



From the data given in my Xiagara book and earlier papers, it will be 

 seen that there is very little deformation about the head of Lake Erie. 

 This increases, so that the rise about the head of Lake Ontario is 2 feet 

 per mile in direction north 22° east. Beyond the outlet of Lake Ontario 

 the eastern equivalent in the rise disappears, but. as in the Mohawk A al- 

 ley the tilting is 3 or 1 feet per mile in a northward direction. This in- 

 creases to 5 or 6 feet per mile on proceeding toward the Saint Lawrence 



'passing this meridian (longitude 76° west) of exclusive northward 

 deformation, the direction of the warping is north 23° west, reaching 6 

 feet per mile, as in triangle number 12, which extends to Panshville. 

 Consequently the isobar of this elevation trends north 67° east. The 

 isobars of any height can be located in the various triangles by drawing 

 lines through the points of equal deformation at right angle to the direc- 

 tion of mean rise in each triangle. 



The direction of the earth-movements is thus seen to bend, after pass- 

 ing Watertown, in conformity with, the change in the course of the 

 "height of land/' east of the 76th meridian. This observation is further 

 shown in the next paragraph. 



Iroquois Plaxe ix the Region of Covey Hill 



If the isobar of Parishville (903 feet) be produced, its course of north 

 67° east passes 4 or 5 miles south of the delta or plain (at 930 feet, 

 barometer, above tide) east of Malone. The continuation of this line 

 passes Covey Hill, where Woodworth and myself noticed the remains of 

 an old water level at about 900 feet. 



But the most important feature about Covey Hill is located on its 

 eastern side, known as the "Gulf." This is a narrow, deep gorge, a few 

 hundred yards in length, situated in an outer canyon over a mile long, 

 with a pond at its head, at an elevation of 915 feet, This corresponds to 



