7-1 THE CANADIAN NATURALIST. [Vol. X. 



able remnant of one of gigantic proportions obscured by hundreds 

 of feet of drift. The question arose, could Lake Erie have ever 

 emptied by this valley? This suggestion did not hold its ground 

 for any length of time, because the present levels are all too high. 

 Near Gait, the traces of the true origin first presented themselves. 

 A branch of the Great Western Railway extends from Gait south- 

 ward for about four miles in the valley of the Grand River, after 

 which, without making any important ascent, it passes into the 

 broad older valley, described above as that in which Fairchild's 

 Creek now flows. After a careful examination of the rei2;ion and of 

 the railway levels, I came to the conclusion that it was an old 

 buried valley. It then became apparent that if the Grand River 

 had occupied the site of the Fairchild's Creek, that the latter 

 probably flowed down the Dundas valley, and that the Grand 

 River, being one of the largest of the rivers of Ontario, might have 

 been a sufficient cause for the s-reat excavation at the western end 

 of Lake Ontario. Having procured all the levels that bore on 

 the subject which were available, it became necessary to connect 

 several places myself by instrumental measurements, which work 

 was accomplished last July, with the aid of Prof. Wilkins. As 

 the whole floor of Niagara limestones is absent, as has previously 

 been shown, the proof that the ancient Grand River flowed down 

 the Dundas valley was completed, and of this discovery there was 

 published a local notice last August. Significant and interesting 

 as this fact was, relative to the change of systems in our Canadian 

 drainage, a still more important issue was involved. When taking 

 the levels between the Dundas valley (modern) and the Grand 

 River, it was found that the whole calcareous floor was removed 

 from a basin several miles in width, and that all the wells were 

 sunk to a considerable depth in the drift before water could be 

 obtained. On glancing at the map it will be seen that the Grand 

 River from Brantford to Seneca meanders through a broad course, 

 which in its ancient basin is several miles in width, but that from 

 Seneca the valley is narrower, and the course of the stream more 

 direct, as far as Cayuga. At Seneca the valley is two miles wide 

 and seventy-five feet deep. Also the bed of the Grand River at 

 Seneca is in drift which is only 37 feet above the lake into which 

 it now empties. This broad valley continues to Cayuga within a 

 few miles of the lake, whence its former probable course was by 

 nearly direct line to Lake Erie, now filled with drift, near the 

 present bend in the river towards the eastward. At Cayuga 



