330 Glacial Phenomena of Canada. 



valley in the rocks, through which an older river ran previous to the 

 drift-period. When the country emerged from the sea, and a new 

 drainage was formed, the river was turned aside by this accumulation 

 finding it easier to form a new channel in the present gorge, 350 feet 

 deep. 



At Onondaga the drift is 640 feet thick. 



Drift is equally characteristic of Connecticut and Massachusetts. In 

 the New Red Sandstane Valley of Connecticut, the drift seemed mixed, 

 but mostly local. 



It is also well known that large far-transported boulders occur on 

 the south bank of the Ohio, — a circumstance less remarkable than at 

 first sight appears, when we consider that it is stated that icebergs have 

 been seen as far south as the Azores. 



Wherever the drift is freshly removed, the rocks are found to 

 be smoothed, striated, and often rounded. On the Isle Perrot, 

 near Montreal, Mr. Billings observed striae running S.W. ; and 

 near Ottawa, by the river, in several places they run south-easterly. 

 These instances are both at low levels ; and during a late period 

 it is easy to understand how, during a former extension of the 

 Gulf of St. Lawrence, icebergs drifting up the Gulf, as they do 

 now, would produce scratches running S.W. in the strait between 

 the Laurentine hills and the Mountains of Adirondack, while 

 in the open sea south of Ottawa (now a great plain) the drift 

 passed in an opposite direction. About halfway between Ottawa 

 and Prescott, on the St. Lawrence, near Kempville, the striae runs S- 

 from 5° to 10° E. on a smoothed surface of Calciferous Sandrock; 

 and at Niagara, on the limestone, S. 30° W., with minor stria- 

 tions crossing each other at various angles. Near Avon, at Conesus 

 Outlet, in the Genesee Valley, on the Corniferous Limestone, the 

 chief striae run S. 10° W., crossed by many minor scratches, having 

 a general southern course. These crossings might be expected, if 

 the striae were produced by floating ice subject to minor variations 

 of the currents, and to the influence of winds. The rock is over- 

 laid by clay containing scratched subangular stones. At Genesee, 

 under 6 feet of drift-clay full of scratched stones, the striae run 

 S. 5° W.; and near Portage, on the top of the gorge, 350 feet 

 deep, the striae run a little west of south. 



The rocks of the St. Lawrence, where it flows from Lake On- 

 tario, deserve more special notice. Above its junction with the 

 Ottawa, the banks of the St. Lawrence are low and shelving, and 

 the rocks are in general obscured by drift ; but between Brock- 

 ville and Lake Ontario, where the river widens and winds amid 

 the intricacies of the Thousand Isles, while the larger islands are 



