Page:Canadian Alpine Journal I, 1.djvu/232

Rh was much larger and far more powerful than at present. The accompanying illustration shows the dividing rock embossment surrounded by moraine and the wildly broken séracs extending across the glacier. The action of the glacier as an irresistible plane, shaving off the mountain side, is well depicted on the left hand.

The main stream of the Yoho river issues from a fine cave which it has hollowed out in the ice-tongue. The front of the forefoot is precipitous, rising sharply about 150 feet. The slope then assumes a more gentle phase, and walking on the ice between the crevasses, which are here longitudinal, is an easy matter.

On the 14th of July, a committee of five members of the Alpine Club left camp with one of the daily parties making the round trip of the Yoho valley. They stopped for the night at Laughing Falls camp and started early next morning for the glacier. On the road they picked up Mr. George and Miss Vaux, who were camped several miles nearer the ice.

Three independent sets of observations were made to establish initial data from which to start a series of annual observations: (1) to obtain rate of flow; (2) to ascertain retreat or advance; (3) to observe the annual change in the ice formation at the snout. For the first, a row of metal plates were fixed in position across the main ice stream. A suitable base line was then carefully measured along the mountain slope on the eastern side, at a height overlooking the ice. While reaching this position, an interesting feature was noticed in a long line of piled-up tree trunks in various stages of decay, parallel to the trend of the glacier. The adjoining slopes have been swept clear of timber by an avalanche, and are now covered by scrub growth and a few small trees, indicating that, at the time of the avalanche, the ice of the glacier was on a level with the tree trunks. It is at the present time several hun-