Dr. G. M. Dawson— Glaciation of British Columbia. 3051 
glacier ice in this region was Iron Mountain, at the junction of the 
Nicola and Coldwater rivers, the summit of which is 3500 feet 
above the neighbouring river valleys, or 5280 feet above the sea.’ 
Evidence of the same kind—all implying the movement of a great 
elacier-mass entirely independent of the local features of the country 
—has now been discovered on several still higher points, the most 
elevated being Tod Mountain, situated 25 miles north-east of 
Kamloops, and rising 7200 feet above the sea. The actual summit 
of this mountain is, however, but lightly glaciated, and in this 
circumstance and the apparent influence which local irregularities of 
rock-surface have had upon the direction of striation, evidence 
seems to be afforded that the summit was never deeply covered by 
the great glacier. This conclusion is further borne out by the fact 
_ that a few hundred feet only lower down the same mountain, the 
glaciation is much stronger, and fluted rock-surfaces and other easily 
recognized marks of heavy glacier ice are observed. Tod Mountain 
is the culminating point of a region surrounded on three sides by 
the wide and important valleys of the North and South Thompson 
Rivers and Adams Lake, the nearest points comparable in elevation 
to it being in the Gold Range, at a distance of over 25 miles in a 
north-easterly direction, or nearly at right angles to the direction of 
the glaciation. There can be no question as to the fact that the 
glaciation met with at this place is due to the general or Cordilleran 
glacier, and it is thus evident that at one period the glacier ice must 
have attained a thickness of about 6000 feet in the valleys above 
named, while it covered even the higher portions of the irregular 
plateau of this part of the interior of British Columbia to a depth 
of at least 2000 to 38000 feet. When it is taken into consideration 
that evidence has already been obtained of the south-easterly motion 
of this part of the Cordilleran glacier for a distance of at least 300 
miles to the north-west of Tod Mountain, it is apparent that the 
mass of névé-ice accumulated over the country north of the 55th 
parallel of latitude from which the southerly- and northerly-flowing 
extensions of the great glacier were fed must have been enormous. 
As previously stated by me, the condition of this part of the 
Cordilleran region, at the period of its maximum glaciation, must 
have been clearly analogous to that of Greenland at the present day, 
save that in the case of British Columbia it has been impossible for 
any large proportion of the ice to escape to the eastward or to the 
westward because of the bordering mountain ranges. 
Some of the principal new localities at which distinct evidence of 
the passage of the Cordilleran glacier over the southern part of 
British Columbia were observed during the summer of 1888, with 
the approximate position and height of each and the direction of 
motion indicated, are given below. The variation in direction found 
in comparing even the highest stations is generally explicable on 
consideration of the influence of adjacent important orographic 
features. A number of observations made at points somewhat lower 
than these here quoted show, as might be anticipated, an increasing 
1 Quart. Journ. Geol. Soc. vol. xxxiy. p. 272. 
