Trees before it were crushed down, and those alongside were thrown into a wild state of excitement by the violence of swiftly created and entangling gale-currents. From the maelstrom on the top I looked down upon the panic through the snow-dust-filled air and saw trees flinging their arms wildly about, bowing and posturing to the snow. Occasionally a treetop was snapped off, and these broken tops swirled wildly about, hurried forward or backward, or were floated upward on rotating, slower currents. The sides of the slide crumbled and expanded; so it became lower, flatter, and wider, as it slid forward on a moderate up grade. A half-mile after leaving the gorge, the slide collided at right angles with a high moraine. The stop telescoped the slide, and the shock exploded the rear third and flung it far to right and left, scattering it over a wide area. Half a minute later I clawed out of the snow-pile, almost suffocated, but unhurt. Toward the close of my last winter as government "Snow Observer" I made a snowshoe trip along the upper slopes of the Continental Divide and scaled a number of peaks in the Rocky Mountains of central Colorado. During this trip I saw a large and impressive snow-slide at a thrillingly close range. It broke loose and "ran"--more correctly, plunged--by me down a frightful slope. Everything before it was overwhelmed and swept down. At the bottom of the slope it leaped in fierce confusion from the top of a precipice down into a cañon. For years this snowy mass had accumulated upon the heights. It was one of the "eternal snows" that showed in summer to people far below and far away. A century of winters had contributed snows to its pile. A white hill it was in the upper slope of a gulch, where it clung, pierced and anchored by granite pinnacles. Its icy base, like poured molten lead, had covered and filled all the inequalities of the foundation upon which it rested. Time and its tools, together with its own height and weight, at last combined to release it to the clutch and eternal pull of gravity. The expanding, shearing, breaking force of forming ice, the constant cutting of emery-edged running water, and the undermining thaw of spring sent thundering downward with ten thousand varying echoes a half-million tons of snow, ice, and stones. Head-on the vast mass came exploding toward me. Wildly it threw off masses of snowy spray and agitated, confused whirlwinds of snow-dust. I was watching from the top of a precipice. Below, the wide, deep cañon was filled with fleecy clouds,--a bay from a sea of clouds beyond. The slide shot straight for the cloud-filled abyss and took with it several hundred broken trees from an alpine grove that it wrecked just above the precipice.