350 A. P. COLEMAN — IROQUOIS BEACH IN ONTARIO 



the larger bays has generally been mapped also when well enough 

 marked to be followed. 



Niagara River to Hamilton 



The cutting of the gorge at Niagara from the front of the escarpment 

 at Queenstown heights is generally held to have begun when the water 

 fell from higher levels to the Iroquois stage, but the lower gorge from 

 the heights toward lake Ontario has not generally been considered in 

 the treatment of the subject. For reasons which will be given later, it 

 is probable that the water level at the beginning of the Iroquois time 

 was much lower than at its end, and that the cutting of the river chan- 

 nel through boulder clay and Medina shale toward the north began at 

 the same time as the main fall commenced its work on the escarpment 

 to the south ; but to what extent the channel was complete when the 

 last and highest stage of lake Iroquois was reached is uncertain. 



The fine bar at Lewiston, with its wonderfully cross-bedded gravels 

 dipping to the south, represents, of course, the final stage of lake Iro- 

 quois and now stands between the contours of 360 and 380 feet above 

 sea, according to the United States survey, or from 114 to 134 feet above 

 Ontario. By hand level I made the highest point at the end of the bar 

 toward the river 122 feet above it, or 124 feet above Ontario ; but Doctor 

 Gilbert, as quoted by Doctor Spencer, makes it 139 feet, having prob- 

 ably found some higher beach level which was overlooked by myself. 



On the Queenstown side gravel deposits were not seen, but the water- 

 line is clearly marked as a cut terrace at the foot of the Niagara escarp- 

 ment, just to the north of the road leading to Saint Davids. It keeps 

 this position for a mile or two west, when the Saint Davids valley cuts 

 far back into the escarpment, and the shore cliff sinks almost to the Iro- 

 quois level with a gently rolling plain to the south, and these conditions 

 last as far as Homer, where gravel bars commence, the shore cliff hav- 

 ing disappeared, and a shallow bay is cut off to the south. 



From Homer to the city of Saint Catharines the gravel bar grows 

 more extensive, and at Saint Catharines it crowds the river, followed by 

 the old Welland canal, a mile or two westward, much as the Don and 

 Humber have been forced westward by gravel bars near Toronto, on the 

 north side of Ontario. At Saint Catharines hand leveling from the 

 Grand Trunk railway station, which is just below the shore cliff, makes 

 the top of the bar 122 feet above lake Ontario. Beyond this the usual 

 low shore cliff extends to the west as far as Fifteen-mile creek, where a 

 ravine discloses stratified gravel, and then to Jordan, where the Niagara 

 escarpment once more forms the shore for a mile or two. From Jordan 

 to Beamsville there is little change, except that the escarpment with- 



