102 J. D. Dana— Flood of the Connecticut River Valley. 



along the steeply escarped Dundas Valley.* He states that in 

 has been penetrated to a depth of 227 feet 

 below the level of the lake without reaching a rocky bottom, and 

 that the depth of the drift is probably as much as 1,000 feet. 

 He also points out. that the channel of Lake Ontario, which has 

 its greatest depth abruptly near the southern side and gradually 

 shallows northward, is a channel of erosion and probablj oi 

 cotemporaneous erosion with that of the Dundas Valley. 



Keported examples of this kind are so numerous that they 

 1 ict. Such exca\ a- 

 ti< aa could not have been made by running water while the 

 land was at its present level ; and much less could they have 

 been made when the land was lower than now. Their origin 

 was hence before the Champlain period in Glacial or pre- 

 Glacial time. 



The accounts speak of these deeply-eroded valleys as filled 

 with drift; and if with true norther,) drift ;is is implied by the 



tioif— they were open to their bottom to receive the drift dur- 

 ing the Glacial era. For otherwise they would be found 

 filled in each case with the sand and gravel of the drainage- 

 area instead of with material from a more northern source. 

 And if open in the Glacial era, the land was at a higher level 

 than in the Champlain period, or that of great deposition ; high 

 enough for a flowing stream to have kept the trenches clear of 

 deposits. Many of these valleys, like that of Dundas Valley, 

 have a different course from that of the movement of the gla- 

 cier, and hence, no aid could have been afforded by the gla- 

 cier in the excavation if the level was as now; and the aid 

 would have been ineffectual whatever the course. 



The facts thus prove that if the material filling these buried 

 valleys is true drift, the land in the <i aei-.d ma wu> higher 

 than now ; and much higher, if the drift of the Dundas Valley 

 is 500 to 1,000 feet deep. The valleys may have been pre- 

 Glaeial in origin, but their depth would have reached its low- 

 est limit from the latest erosion or that of the Glacial era. 



The argument from the deep river-made channels intersect- 

 ing sea-border regions, and now occupied by the sea — that is 

 from long bays and fiords 100 to 3,000 feet" or more in depth 

 of water — which characterize the shores in the higher latitudes 

 on all the continents, north and south, still stands good so far 

 *Proc. Amer. Phil. Soc. 1881, and Proc. Amer. Assoc. Adv. ScL 1881. 



