Now it was a roaring mass with a front steadily increasing in height, and far away in the rear it tossed up a tail of snow dust, a flying mist that gave Bull an impression of speed greater than the main wall of the snow itself.
The noise grew amazingly, and coming in range of the opposite wall of the valley, a low and steadily increasing thunder poured into the ears of Bull.

It was a fascinating thing to watch, and at this distance to the side he was quite safe.

But at the very moment that he reached this decision, the front of the slide smashed with a noise like volleyed canyon against the side of a hill, tossed immense arms of white in the air, floundered, and then veered with the speed of an express train rounding a curve and rocked away down the slope straight for Bull.

Turned cold with dread, he saw it hit the timberline with a great crashing, and the dark forms of the trees were dashed up by the running mass of stones and then swallowed in the boiling front of the slide.
He waited to see no more, but dashed on for the saving cliff.

Once his back was turned it seemed that the slide gained speed.