REVIEWS 505 



sand in these valleys, the cobble bars, the wave-cut terraces, the deltas, 

 and many other evidences of high-level standing water, with no known 

 barriers to hold this water in, is strong evidence that the land in this 

 region once stood below sea-level. This marine shore line has been 

 uplifted and tilted and is now less than 100 feet above sea-level a short 

 distance north of New York City and 740 feet above sea-level at Covey 

 Hill on the International boundary, a distance of about 350 miles. 

 Diagrams are given to show the profile of this tilted marine shore line 

 and also the shore line of Lake Iroquois, the last of the glacial lakes to 

 occupy the Ontario basin. In the St. Lawrence-Ontario basin the 

 Iroquois plane is 290 feet above the marine plane and thus when one is 

 found in the field it is easy to locate the position of the other. Also 

 knowing the present elevation of these two planes and the total amount of 

 uplift of the region, the amount of either glacial or post-glacial uplift 

 can easily be determined. From numerous measurements and calcula- 

 tions of this sort it appears that northern New York State was not raised 

 as a rigid body but by a progressive wave movement, as the southern 

 side of Iroquois basin received one-half its total uplift during Iroquois 

 time while the northern end of the same basin received very little 

 uplift until after Iroquois time. The uplift of the land seems to 

 have been wavelike and to have followed the margin of the retreating 

 ice front. 



Detailed descriptions of shore features in the various sheets along 

 the Hudson, Champlain, and St. Lawrence valleys and the Ontario 

 basin are given. The shore features at Covey Hill, the point of junction 

 of the Champlain and St. Lawrence valleys and of the Champlain marine 

 waters and the Lake Iroquois waters, are described in detail. Some of 

 these shore features are at present somewhat above what the level of the 

 water should have been at these particular localities. Many complica- 

 tions probably enter the Pleistocene history as there may have been 

 many up-and-down land movements and the present height of the 

 summit plane above the sea must represent only the excess of land 

 uplift over the rise of the ocean surface and the arithmetical sum of 

 aU the up-and-down movements. 



A large number of photographs are inserted to show summit shore 

 features and at the end of the report a classified bibliography is given. 

 This report summarizes in a very thorough and clear manner Professor 

 Fairchild's interpretation of the various glacial and post-glacial deposits 

 and physiographic features of this region. 



J. F. W. 



