LINE OF THE CANADIAN PACIFIC RAILWAY. 387 
buffalo as rubbing-stones, and are surrounded by basin-shaped 
depressions formed by the feet of these animals *. 
That strong currents of water have traversed this upper plain, is 
shown not only by the occasional ridges of gravel, but by the 
depressions known as “slues,” which must have been excavated 
subaqueous currents. 
Near Medicine Hat a terrace of boulders was seen at an elevation 
of about 200 feet above the river ; and in sections of the drift observed 
in coulées, the boulders were seen to be arranged in layers; but 
whether these appearances had relation to fluviatile action, before 
the excavation of the deep valley of the Saskatchewan, or belonged 
to the original distribution of the drift, was not apparent. 
Laurentian boulders were seen all the way to Calgary, but with 
an increasing proportion of quartzite boulders from the Rocky 
Mountains ; and on the banks of the Bow river were large beds of 
rounded pebbles which must have been swept by water out of the 
valleys of the mountains, and are quite similar to those now observed 
in the bed of the Bow itself. 
Beyond this, Dr. G. M. Dawson has recorded Laurentian boulders 
and fragments of limestone from the eastern Paleozoic beds, at 
elevations of from 4200 to 4660 feet, at the foot of the Rocky Moun- 
tains, evidencing a driftage of at least 800 miles, and an elevation con- 
siderably above that of the sources from which they came. He well 
observes that any thing which would explain the origin of the coteau 
must also explain the transport of these boulders so far above it and 
beyond its limits, as well as the contemporaneous distribution of 
boulders from the Rocky Mountains to the eastward. These pheno- 
mena are explicable on the hypothesis of a glacial sea of varying 
depth, but not on that of land glaciation, which would also be 
inapplicable in a region necessarily of so smail precipitation of 
moisture and occupied by soft deposits so little suited to the move- 
ment of glaciers. There is nevertheless good evidence of the action 
of glaciers on a large scale in certain portions of the glacial period 
both on the Rocky Mountains and on the Laurentian hills and 
table-lands to the east. 
My observations of 1883 were extended only as far as the railway- 
cuttings then in progress a few miles west of Calgary ; but the road 
now extends 120 miles further through the disturbed and folded 
portions of the Laramie and Cretaceous, and the portions of the road 
to be opened this summer in the mountains may be expected to 
afford interesting exposures of these, as well as of the Paleozoic 
rocks which constitute the nucleus of the Rocky-Mountain chain. 
* The buffalo is now extinct on these plains; but abundant traces of its 
former presence exist in the rubbing-stones, wallows, deeply-worn paths, and 
bleached skeletons, and at one place on the Bow river we saw a large deposit of 
bones covered with earth washed down from above, and apparently indicative of 
the destruction of a herd from some natural cause, perhaps unusual cold and 
heavy snow. The latter, when followed by thaw and frost, producing a hard icy 
erust, has sometimes proved destructive to cattle on the higher plains. 
