REPORT OF THE DIRECTOR I915 185 



from the 120 foot contour near the present lake shore to the 200 

 foot contour. The village of Crown Point stands on this marine 

 terrace, at approximately the 180-200 foot contours. 



The southern shore line of this bay skirts the base of Sugar hill 

 near the 200 foot contour. Bare wave-cliifs are exposed behind the 

 schoolhouse, and a gentle shore line traverses the park near the old 

 brick store and the soldiers' monument. The three Hammond 

 houses stand on clay knolls where the till sheet rises above the 

 marine level, while the Congregational Church and the parsonage 

 stand on the sandy delta terrace. 



Farther west, the marine shore line can be seen where it crosses 

 the top of Brevoort hill from north to south by Mr Barney's house. 



Between Sugar hill and Breed hill a tiny brook runs eastward 

 to the lake down the bottom of the old cove (plate 4, upper figure). 

 It cuts the strip of marine clay to reach the lake, but between the 

 160 and 180 foot contours it formed a delta. This is a loamy ter- 

 race several acres in extent. It lies to the south of the present 

 course of the brook. The state road crosses it near Joe Ross's 

 house as it skirts the northeast base of Breed hill. 



7 SUBSEQUENT MODIFICATIONS OF TOPOGRAPHY 

 Tilting 



The shell deposits that have been discussed above give the best 

 evidence to be had to show the extent and rate at which the land 

 has risen since glacial times. According to Woodworth (1905, 

 p. 205) " The marine limit of this epoch is now tilted more steeply 

 to the south than the shore lines of the earlier water levels [are 

 tilted] to the south. It appears to follow from the divergence of 

 these ancient water plains that before the invasion was established 

 the land was tilted down to the north, thus determining the extent 

 of the submergence ; since then the land has risen." 



The subsequent elevation of the land to the north has raised these 

 shell deposits far above the present sea level. At Montreal they 

 are found at from 540-560 feet above tide, according to Spencer.^ 

 Professor Goldthwaite, General Lamothe and Professor Wood- 

 worth collected Saxicava rugosa on Mount Royal at an 

 elevation of 585 feet. At Crown Point (Fort Frederick) they 

 occur at about 100 feet. Between these two points the shells are 



1 Spencer, J. W., 1912, p. 471. " Dawson's figure of 560 feet has been corrected 

 on the recent Canadian Geological Survey map to 572 feet from datum frorn 

 Lake St Peter to mean tide at New York." 



