On scree at a lower angle we shall have to continue the plunging strides, leaping from heel to heel and travelling as far as possible on the stones set moving by each foot. The stronger the leg the longer may be the stride. The massing of the stones under the foot will stop each step with the softness of a slow spring, and if we are thrown out of balance by one too abrupt foot check, we can generally recover it on the next stride.
Towards the end of the slope the scree grows larger, and whether sliding or plunging, we have to look out for knee and ankle twisting. We go cautiously, but driving always harder with the heel, until the stones refuse to yield to the thrust; and then we call in our loose legs under control, and proceed to stumble or dance down the rest according to the perfection of our ankles and balance. A man light of foot and supple of joint can let his feet drift, as it were, over even large rolling stones, letting them adjust themselves to the varying resistances without checking his pace. A man who judges his scree not by its size but by its angle, its shape and the way it sits on the surface, can continue his glissade often well beyond the point where the less expert begin to fall or crawl.
Once the blocks grow too big to be kicked into harmless motion, and the drifting feet begin to slip over them into the interstices, the wise man begins to look for other shoots to carry him farther. By using the swinging cross-step described already, we can make diagonal descents of slopes on a succession of connected parallel glissades. By choosing a line well ahead, and crossing from shoot to shoot, many hillside descents of weary prospect can be charmed into a few moments of stimulating racing. It is well to remember that up-running spits of light scree often conceal themselves in depressions between ribs of rock or in hollows between slopes of heavier scree, especially near the bottom of the slopes.
The light screes that lie in these lower furrows on hillsides are among the deepest and pleasantest. Our zagging from furrow to furrow will divert our thoughts if not our feet from the last tiresome steep grass drop. Where the lower spits of light shilla thin out, generally at their lower ends, it is wise to look out for the catch to the ankle of rocks or wet earth or grass, stripped of their scree varnish by the driving heel.
It is best for each member of a party to choose a different line, otherwise the larger stones dislodged, often accumulating a torrent, may surprise a speedier forerunner. Similarly, it is safer to leap sideways occasionally ourselves, and wait while our own attendant torrent passes.
The angle of inclination at which small scree lies is invariably the angle of disinclination for big scree. Big scree, when we cannot avoid it, is an unqualified worry, and we worry out of it as we can. The method, traditionally recommended, of sitting or standing on one large stone and tobogganing down on it over the others, would seem to be only successful for distances not yet ascertained.
In Winter Gullies.
Except in the North, where winter snow gives much the same conditions for glissading as the summer Alps, winter glissading in Britain is usually upon snow-covered scree or mixed snow and scree. The end of our glissades in this case has a special risk: where the snow thins and weakens among the larger blocks, which it yet continues to cover—to our downfall. To glissade near emerging rocks is risky, on account of the probable holes and hidden pockets in the snow round them.
In gullies alone we find snow over rock. Here there is another special risk in the rock steps or pitches, which may be only partially covered with snow. The drop is often invisible from above, and an inexperienced glissader may be unable to stop himself in time, when he is close enough to recognize a break in the continuity of the snow slope. Sometimes there is a frail lid of snow more deceptive than an open break; and I have seen a man shoot over a pitch of this sort through the snow lid and down the wet rock channel under the lower snow. Where the rock of such pitches is visible, we have still to look out for another trap. We may count upon stopping as we reach the rock; but the very end of the slope, where the melting snow has run down and refrozen over rock, is usually of harder surface, if not of ice. Hence we have to allow for a sudden and surprising acceleration just where we intended to slow up.
No man should start glissading down a gully or slope that he does not know; or that he cannot see throughout its whole length; or until he is expert enough to know what the snow, as he finds it, will do with his feet.