THE 



CANADIAN NATURALIST 



AND 



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DISCOVERY OF THE PREGLACIAL OUTLET OF 

 THE BASIN OF LAKE ERIE INTO THAT OF 

 LAKE ONTARIO ; WITH NOTES ON THE ORIGIN 

 OF OUR LOWER GREAT LAKES. 



The above is the title of a lengthy paper by Prof. J. W. 

 Spencer, of King's College, Windsor, N. S., read before the 

 American Philosophical Society in March last. 



We present our readers with the more important parts of the 

 paper concerning the Preglacial Outlet of Lake Erie and a sum- 

 mary of the whole. 



Basin of Lake Oiitar'iG. As is well known. Lake Ontario 

 consists of a broad, shallow (considering its size) basin, excavated 

 on the southern margin out of the Medina shales, and having its 

 southern shores from one to several miles from the foot of the 

 Niagara escarpment. The Medina shales form the western 

 margin (where not covered with drift) to a point near Oakville. 

 From this town to a point some distance eastward of Toronto, 

 the hard rocks are made up of the different beds of Hudson River 

 Epoch; while the soft Utica shales occupy the middle portion, 

 and the Trenton limestones the portion of the Province towards 

 the eastern end of the lake. 



The country at the western end of the lake consists of slopes 

 gently rising to the foot of the Niagara escarpment. Sometimes 

 this elevation is by terraces, and again by gentle inclines, as 

 between the foot of the encarpment at Limehouse (on the G. T. 

 Railway) and the lake, where the difference of altitude above the 

 water is more than 700 feet, without any very conspicuous features. 



Vol. X. E No. 2. 



