No. 4.] SPENCER — SURFACE GEOLOGY. 229 



•emptied by this valley? This sug;^estion did uot hold its grouud 

 for any length of time, because tlie 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 

 rsouthward 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 Fair- 

 •childs creek now flows. After a careful exauiin ition ol" the 

 region, and of the railway levels, I came to the conclusion that 

 this was an old buried valley. It then becam ; app ireut that if 

 the Grand river had occupied the site of the Fairchilds'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, 

 misjht have been a suflficent cause for the great excavation at the 

 western end of Lake Ontario. 'H;iving procured all the levels 

 that bore on the subject which were available, it became neces- 

 sary to connect several places myself by instrumental measure- 

 ments, which work w.is accomplished 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 :t local notice iu August, 1880. 

 Significant and interestinj: as this fact was, relative to the chaujje 

 •of systems in our Canadian drainage, a still more important issue 

 was involved. When taking the levels between the Dundas val- 

 ley (modern) and the Grand river, it was Ibund that the whole 

 calcareous floor was removed from a b isin 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 ba^in is 

 :several miles in width, but that from Seneca the valley is nar- 

 rower, 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, 

 <is has been pointed out in the section. 



Having observed the connection between the Dundas valley, 

 Grand river and Lake Erie, it dawned on me that I had esti- 

 'blished the knowledge of a channel having a very important 

 bearing on the surface geology of the lake region. It now be- 



