Glaciatlon of British Columbia. ^Dawso)i- 251 
ed, the direction on the summit being that of the main (north- 
north-west) orographic valleys, while that at lower levels in 
the same vicinity followed more nearly the immediate valley 
of the river, which here turns locally to the east of north. 
Glaciation was also noted in several places in the more moun- 
tainous country to the south of the Yukon basin, in the Dease 
and Liard valleys, but the direction of movement of the ice 
could not be determined satisfactorily, and the influence of 
local action is there less certainly eliminated. 
Of the glacial deposits with which the greater part of the 
area of the inland region is mantled, it is not intended here to 
give any details,though it may be mentioned that true Boulder- 
clay is frequently seen in the river-sections, and that this gener- 
ally passes upward into, and is covered b}^, important silty beds, 
analogous to the silts of the Nechacco basin, further south in 
British Columbia, and to those of the Peace River Country to 
the east of the Rocky Mountains. It may be stated also that 
the country is generally terraced to a height of 4,000 feet or 
more, while, on an isolated mountain-top near the height of 
land between the Liard and Pelly rivers (Pacific-Arctic water- 
shed) rolled gravel of varied origin was found at a height of 
4,300 feet, a height exceeding that of the actual watershed by 
over 1,000 feet. 
Reverting to the statements made as to the direction of the 
general glaciation, the examination of this northern region 
may now be considered to have established that the main 
gathering-ground or neve of the great Cordilleran glacier of 
the west coast, was included between the 55th and 59th paral- 
lels of latitude in a region which,, so far as explored, has 
proved to be of an exceptionally mountainous character. It 
would further appear that this great glacier extended, between 
the Coast Range and the Rocky Mountains, south-eastward 
nearly to latitude 48°, and north-westward to lat. Go°, or be- 
yond, while sending also smaller streams to the Pacific Coast. 
In connection with the northerly direction of ice-flow here 
mentioned, it is interesting to recall the observations which I 
have collected in a recently published report of the Geological 
Survey, relating to the northern portion of the continent east 
of the Mackenzie River.® It is there stated that for the 
'^ Notes to accompany a Map of the Northern Portion of the Dominion 
of Canada, East of the Rocky Mountains, p. 57 R. Annual Rejiort, ISSB. 
