476 A. W. G. WILSON SHORELINE STUDIES ON ONTARIO AND ERIE 



A study of old maps of Toronto harbor shows that there has been a 

 progi'essive growth westward since the first map was prepared^ in 1793. 

 The record of successive recurvements at the western end of the island is 

 still preserved in the numerous lagoons found on the island at this end. 

 Sir Sanford Fleming/ in an able article read before the Canadian Insti- 

 tute in 1850, attributes the groundwork of the peninsula to the Don 

 river. The peninsula proper he attributes solely to the mechanical action 

 of the waves. The sand and gravel of which it is composed he considered 

 to have been transported from the eastward gradually and deposited on 

 the delta of the Don, and the delta was then raised above the surface of 

 the water and extended far beyond its original limits. "While the -writer 

 agrees in the main with this opinion, he is inclined to attribute to the 

 Don and its delta a very minor importance. 



one Mile. 



PiGTJEB 1. — Toronto Island, ISSO 

 City Engineer's Survey 



The Don, the Humber, the Eouge, and a number of other streams in 

 the district have cut wide, deep valleys in the glacial debris back of the 

 lake shore and have undoubtedly brought large quantities of material 

 down to the shore. A very considerable portion of this erosion took 

 place not only prior to the building of the peninsula, but also prior 

 to the formation of the present lake. Evidence of this is found in the 

 fact that east of Toronto there are a number of valleys which show 

 mature development and grading accordant with abandoned lake levels 

 below the Iroquois but above the present lake level, and more recent ad- 



2 Proceedings of the Canadian Institute, vol. ii, 1853-1854, pp. 105-107 and 223-230. 



