412 J. W. S/xni-rr — Trrrorrs about Lake Ontario. 



and 830 feet above Lake Ontario. Near Owen Sound there 

 are others at 546, 496 and 466 feet above Lake Ontario. 



Along the Great Western Bailway, adjacent to the valley of 

 St. David's (near the Niagara Kiv.-i i. ih.-iv an- stratified sands 

 and gravels (of Hudson River epoch) from 383 to 250 feet above 

 the lake. 



In New York State, eastward of Lockport, the lake ridges 

 rise from 158 to 190 feet above the lake (Hall). On the south- 

 eastern margin of the lake basin there are old beaches at 400 

 feet, and at the north end of Skaneateles Lake, at about 625 

 feet above Lake Ontario, there are still others. But the col- 

 lected records of the New York terraces are too fragmentary 

 for general comparison. 



In theappended table the reader will be immediately impressed 

 with the relationship existing between the beaches at the various 

 elevations which surround the lake, and the continuity of the 

 slow recession of the waters. The higher beaches, of course, refer 

 to the time when the waters of all the Great Lakes were united 

 in one body. In Michigan there are beaches at 1350 feefcabove 

 Lake Ontario. Near Petits Ecrits, Lake Superior, beaches at 

 398, 408, 458, 592, 627, 635 and 699 feet above Lake Ontario 

 were measured by the Geological Survey of Canada, 



Again to the southwestward of Lake Erie, Messrs. Gilbert 

 and Winchell measured beaches or ridges at 65-90, 165, 195, 

 220, 350-408, 386-490 feet above Lake Erie. 



The belt of the Artemesia gravel may approximately be rep- 

 resented by the contour line of 1250 feet above the sea, but 

 extending southward of this line to somewhat beyond the con- 

 tour of 950 feet. It is thus described by Dr. Bell : " This great 

 belt of gravel has a ge <. the Niagara escarp- 



ment and follows the highest ground of the peninsula. The 

 materials composing it consist principally of the ruins of the 

 Guelph formation, on which the greater part lies, except to- 

 ward the southern extremity, where the Niagara formation is 

 largely represented. Pebbles of Laurentian and Huronian 

 rocks are everywhere mixed with the others, and sometimes 

 form a considerable proportion, while rounded fragments from 

 the harder beds of the Hudson River formation occur locally in 

 some abundance." (These last rocks are derived from lower 

 levels.) ''The gravel is all well rounded and generally coarse. 

 It often constitutes what might properly be called 'cobble 

 stones,' being loose and free from any admixture of clay ; and 

 it is distinctly stratified. Well worn boulders of Guelph, Lau- 

 rentian and Huronian rocks are dis h the whole 

 mass." In a few places this gravel overlies blue Erie clay. 

 From the eastern side of the Artemesia gravel ridges, there 

 extends a long comparatively narrow ridge for about 100 miles 



