344 R. S. TARR — LAKE CAYUGA A ROCK BASIN. 



hand, it seems well to state his views, since they are exactly those to 

 which Ave are driven by recent studies. While his conclusions seem cor- 

 rect, his reasons were not convincing, as will be seen by an examination 

 of the following pages, in which the opinions of later students are given- 

 He says,* Ontario and the other lakes — 



"are excavated basins, wrought out of once continuous sheets of sedimentary 

 strata by a mechanical agent, and that ice or water, or both." 



Again he says : t 



"No other agent than glacial ice, as it seems to me, is capable of excavating 

 broad, deep, boat-shaped basins like those which hold our lakes." 



Essentially these conclusions are repeated by this author in other 

 publications, both earlier and later.J In one of them § he says : 



"I had claimed the existence of an ancient river flowing from Lake Superior 

 through the lake basin and down the Mohawk valley into the trough of the Hud- 

 son, and thence to the ocean by New York. The valley of this stream, locally 

 expanded into boat-shaped basins by glacial action, according to my view, formed 

 the basins of the Great lakes." 



Simonds II shows that there are iu this region two classes of valleys — 

 gorges, " true valleys of erosion," and rounded, smoothed valleys. Of 

 the latter he says : 



'' Notino; in addition (to their even slope) the depth at which the water flows, 

 and the small number of cascades and waterfalls, the conclusion is at once reached 

 that these valleys have been acted upon by some agency not now in operation." 



He can easily understand the gorges, but cannot explain the broad 

 valleys by erosion, and therefore concludes that " these deep, well worn 

 valleys are undoubtedly the result of glacial action." According to this 

 author, the glacier divided near the present site of Ithaca, one lobe mov- 

 ing southward, the other carving out the valley of Six-mile creek. 



This, which seems to be the first statement of the glacial origin of 

 Cayuga valley, is based upon the inability of the author to conceive of 

 the formation of a broad, deep valley by river erosion and transporta-. 

 tion. It seems strange that he should not have noticed that this valley 

 was but one of a type which exists in that region with directions vary- 

 ing through all degrees of the compass, and hence that all are not capa- 

 ble of explanation by glacial erosion. 



* Geological Survey of Ohio, vol. ii, 1874, p. 72 



t Geological Survey of Ohio, vol. ii, 1874, p. 74. 



JProc. Boston Soc. Nat. Hist., vol. ix, 1862, pp. 42-46; Annals New York Lyceum Nat.. Hist., vol. ix, 

 1870, pp. 213-234; Proe. New York Lyceum Nat. Hist., vol. ii, 1874, pp. 136-138; Proe. Am. Phil. Soc. 

 vol. XX, lS82-'83, pp. 91-95; and elsewhere. 



gProc. Am. Phil. Soc, vol. xx, 1882-'83, p. 93. 



U Am. Nat., vol. xi, 1877, pp. 49-51. 



