rough bowlders and tangling underbrush.

Of a sudden a low rumbling sounded faintly from seemingly beneath their
feet. The ground wavered dizzily. Trees swayed, rocks started rolling
down the canyon side, and the very bowlder they were on tilted till they
had to make a quick leap for it. It was just one of the slight
earthquake shocks to which all Californians are accustomed. But never
before had either Norris or Long Lester been on such dangerous footing
when one happened.

Quick as thought, the old man went leaping up over the bowlders, yelling
frantically to Norris to follow him. The geologist knew in a theoretical
way what to do when a snow-slide threatened, and with that lightning
speed with which our minds work in an emergency he had seen that the
shock of the 'quake would precipitate snow-slides, and that they were
directly in the path of one.

He knew theoretically,--as the old prospector knew from observation of
several tragedies,--that the river of snow and rock-slide would flood
down canyon till it came to a turn, then hurtle off in fine spray--on the
side of the curve! (It all happened in an instant.) Their one salvation
lay in taking the _short_ side of the curve,--though the going was
rougher.

With the roar of an express train,--whose speed it emulated,--the
oncoming slide tore down at them. Down 3,000 feet of canyon the crusted
snows of what was still spring at that altitude rushed like a river at
flood. The wind of its coming swayed tall trees.

The two men escaped by the skin of their teeth!

"It shore would'a scrambled us up somethin' turrible!" the old man kept
exclaiming.

Next day, he knew, they would find a clean swath cut down the
mountainside,--tall pines swept away, root and branch. He had seen many
of these scars, which in later years had become a garden of fire-weed and
wild onion, a paradise for birds and squirrels and onion loving bears.

He had seen steep mountains fairly striped by the paths of slides, the
forest still growing between stripes. For the steeper the slope, the
swifter the slide, as might be expected.

Lucky for them this had been a Southwest slope; for on the North, away
from the sun, a slide is even swifter!

He had seen one man buried by crossing the head of a slide which gave way
under his foot. Its roar had been heard for miles. Frost-cracked from the
solid granite, the side rock that accompanied it had been weathered from
the peak. Thus are high mountains wo