4 The Ancient Glaciers of the Rocky Mountains. [January, 
than among the Uintah and Wasatch mountains, three hundred 
and fifty miles further south. Here then was a great glacier ~ 
moving northwards, while in British Columbia, on a parallel only 
about two hundred and fifty miles further north, there was a mas- 
sive ice-sheet moving southward. It will be a point of no little 
interest to trace these two converging ice streams towards each 
other. : 
In ascending the Yellowstone valley towards the National 
Park, scattered moraine-mounds and abundant transported blocks 
continue to denote the course and size of the former glacier. I 
was wholly unprepared, however, for the intense glaciation of the 
second cafion. This ravine had been cut to a depth of at least 
eight hundred or one thousand feet in the schists and other older 
crystalline masses of the region. At its lower entrance a few 
prominent rocky knobs project from the steep declivity upon the 
flat alluvium on the left bank of the river. Great was my aston- 
ishment to find these spurs of the mountain-side as perfectly 
smooth, polished and striated as those at the margin of any Swiss 
or Norwegian glacier. The strize were directed upward over the 
ridge, and showed how the ice had been pressed out of the gorge 
- over this opposing barrier of rock, The steep sides of the cafion 
have been ground smooth and striated in the same way, as far up 
as I could see, certainly not less than eight hundred feet. Even 
from below the eye could follow the deep parallel scorings along 
the ice-worn sheets of gneiss. The glaciation reminded me more 
of the valley of the lower Aar glacier, above the Grimsel, than of 
any other European piece of ice-work. As the ice-worn surfaces 
descend to the modern alluvium of the river, it is clear that there 
has not been any large amount of erosion in the cajfion since the 
_ glacier left the scene. I think it is equally certain that the cafion 
already existed before the glacial period, and that the work of the 
ice has been to grind it out deeper and wider. 
Above the second cafion the moraine-heaps become more 
abundant and tumultuous. Here and there they enclose small 
lakes. The tributary valleys too have their moraines and erratics 
and must have been filled up with ice. Impressive testimony to a 
the magnitude of these ice-masses, is found in that section of the 
Yellowstone and its surroundings, between Gardiner’s river and — - 
Mount Washburn. The trail from the Mammoth springs by 
Blacktail Deer creek, over to the Yellowstone, leads the traveler e 
