Niagara Falls 



1898 to a depth of 240 feet. In thus establishing the ancient drainage 

 Spencer Q f t ^ e Ontario basin, after years of observation, often represent- 



ing but little progress, the phenomena of the basin were discov- 

 ered without the glacial theory of erosion. Then the writer 

 found that the drowned channels across Lake Huron, and pass- 

 ing through Georgian bay, continued beneath hundreds of feet 

 of drift, eastward of the Niagara escarpment, and joined the 

 Ontario valley a few miles east of Toronto. A similar channel 

 (the Huronian) crossed the State of Michigan, passed through 

 Saginaw bay, and over the sub-lacustrine escarpment, to the 

 deeper channel of the Huron basin. 1 The Erie (Erigan river) 

 drainage had been found to pass into the head of the Ontario 

 basin. Thus was discovered the course of the ancient Laurentian 

 river and its tributaries of antiquity. These upper basins were 

 also affected by the terrestrial tilting recorded in the beaches, as 

 well as by the drift obstructing them. 



Prof. Gilbert, who had, many years before, mapped beaches 

 at the head of lake Erie, 2 afterwards measured the deformation 

 recorded in the deserted shore at the eastern end of the lake; 

 while the writer surveyed the old water margins across Michigan, 

 and on the Canadian sides of Lakes Ontario, Erie and Huron, 

 and in portions of New York/ After this, very little work was 

 done upon the deserted shores for several years, when Mr. F. B. 

 Taylor commenced his researches about the northeast portion of 

 Georgian bay, Lake Michigan, etc., 5 and Dr. A. C. Lawson 



1 Origin of the basins of the Great Lakes. Q. J. G. S. (Lond.), 

 vol. XLVI, 1890, pp. 523-533. 



2 See Geology of Ohio, II, 1874. 



8 The history of the Niagara river. 6th Rep't Com'rs State Reserv. 

 Niag. 1890, pp. 61-84. 



4 The Iroquois beach, cited before. Deformation of the Iroquois 

 Beach and Birth of L. Ontario, Am. Jour. Sci., XL, 1890, 443-451 ; 

 Algonquin Beach and L. Huron, XLI, 1891, 11—21; High Level 

 Shores in the Region of the Gt. Lakes, and their Deformation, XLI, 

 1891, 201-21 1 ; Lundy Beach and L. Erie, XLVIII, 1894, pp. 207- 

 212. 



5 Numerous papers recently published in Am. Jour. Sci., Am. Geol., 

 and Bull. Geol. Soc. Am. 



616 



