206 Cincinnati Society_of Natural History. 
south side of Echo lake 8. 55° W.; half a mile below S. 70° W.: in a 
depression north of Walker lake S. 17° W.; Thessalon river above 
Rock lake S. 25° W.; west and south sides of Rock lake S. 15° W.; 
east side of bay at Bruce Mines S.; northwest end of Wahbiqueko- 
bingsing lake 8.; southeast end of same lake S. 12° W. 
Instances* of the abraded and polished surfaces of rock are very 
numerous on the Canoe route from Lake Superior to Lake Winnipeg. 
Near Baril Portage, 143 miles from Lake Superior, and 1,500 feet 
above the sea, gneissoid hills and islands are smooth and sometimes 
roughly polished on the northerly side, while on the southern side 
they are precipitous and abrupt. On Sturgeon lake, 208 miles from 
Lake Superior, and 1,156 feet above the sea, the northeastern extremi- 
ties of hill ranges slope to the water’s edge, and when bare are always 
found to be smoothed and ground down. The aspect of the south and 
southwestern exposures, is that of precipitous escarpments. The 
summits of the granite hills near Lake Winnipeg are abraded and 
frequently so smooth and polished as to make walking upon them 
difficult, if not impossible in moderately steep places. ' 
On the south branch of the Saskatchewan the drift is exposed in 
cliffs 50 to 80 feet in altitude at the bends of the river. The drift con- 
sists of clay with long lines of bowlders ‘in it at different elevations. 
Some of the fragments of shale, slabs of limestone and small bowlders 
imbedded in the clay, stand in the drift with the longest axis vertical, 
others slanting, and some are placed as it were upon their edges. Long 
lines of bowlders lie horizontally from ten to twenty feet below the 
surface or top of the cliff, while below, in many places, close to the © 
water’s edge, and rising from it in a slope for a space of 25 to 30 feet, — 
the bowlders are packed like stones in an artificial pavement, and 
often ground down to a uniform level by the action of ice, exhibiting 
ice grooves and scratches in the direction of the current. This pave4 
ment is shown for many miles in aggregate length at the bends of the © 
river. Sometimes it resembles fine mosaic work, at other times it is 
rugged, where granite bowlders have long resisted the wear of the ice, 
and protected those of softer materials lying less exposed. i 
Two tiers of bowlders, separated by an interval of 20 feet, are often 
seen in the clay cliffs. The lower tier contains very large fragments of 
water-worn limestone, granite and gneissoid bowlders, above them 
is a hard sand containing pebbles; this is followed by an extremely — 
fine stratified clay, breaking up into excessively thin layers, which 
* Assiniboine and Saskatchewan Expl. Exped. 
