18KI.J ^^^^ [Spencer. 



a mile long, 300 feet deep and between 200 and 300 yards wide at its mouth. 

 At the head of this is Spencer Falls, 135 feet high, and joining it laterally 

 there is another canon, witli a considerable stream flowing from Webster's 

 Falls, which, however, is of less height than the other. The waters feed- 

 ing their streams come from northward of the escarpment, and belong to 

 a system of drainage diSerent from those streams which flow down through 

 the drift of the Dundas valley, and are of much greater length. At the foot 

 of Spencer Falls, the waters strike the upper portion of the Clinton shaly beds. 

 The Falls now are two feet deeper than twenty years ago. Yet the stream 

 is small, and makes a pond below in the soft shales. Bat this difference in 

 height does not represent the rate of wearing or recession of the precipice. 

 That the stream is much smaller than formerly is plainly to be seen, for at 

 present it has cut a narrow channel, from ten to fifteen yards in width, 

 above the falls, and from four to six feet deep, on one side of the more 

 ancient valley, which is about 50 yards wide and 30 feet deep, excavated in 

 the Niagara dolomites. 



The surfaces of the escarpment in both sides of Glens Spencer and 

 Webster present a peculiar aspect. That on the north-eastern side has a 

 maximum height of 520 feet above the lake. On the same side, a section 

 made longitudinally shows several broad shallow glens nearly a hundred 

 feet deep crossing it and entering Glen Spencer. The surface of the 

 rocks is glaciated, but not parallel with the direction of the channels. 

 On the south-western side of the same canon, we find that a portion of 

 the thin beds of Upper Niagara limestone have been removed. This ab- 

 sence is not general, for it soon regains its average height of about 500 feet. 



Dundas Marsh. The eastern end of the Dundas valley contains a large 

 swamp, nearly three miles long, with a breadth of about three-fourths of a 

 mile, known in the early settlement of the country by the name of Coote's 

 Paradise. 



This marsh was formerly connected by a small rivulet with Burlington 

 bay, but this was subsequently closed by the G. W. Railway, when the 

 cutting of Desjardin's canal through Burlington heights was completed. 

 Into this marsh all the drainage of the Dundas valley is deposited, causing 

 it to fill up at the rate of one-tenth of a foot per annum. 



Burlington Heights. Across the eastern end of the Dundas swamp and 

 some of its branches, are the Burlington Heights, varying from a few hundred 

 yards to nearly a quarter of a mile in width, and over 100 feet in height, which 

 have been an old beach, at a time when the lake level was at the same eleva- 

 tion, for we find that a lake beach extends along the flanks of the escarp- 

 ment, both eastward and northward for a considerable distance at the same 

 level. This is mentioned here as forming a most conspicuous terrace, 

 and as changing the physical character of the western extremity of Bur- 

 lington bay, and the outlet of the Dundas valley. Various terraces and 

 beaches are found, both at lower levels, and also fragments at higher alti- 

 tudes, or along the side of the "mountain," until some attain a height of 

 500 feet above Lake Ontario. 



