Snow slope

“ The thaw seemed to have ceased and an icy wind got up, moaning dismally in the tree-tops. The river, which had been always rather narrow, widened out within a sort of gorge of rocks and brushwood. The bed of it began to slope slightly in a long series of what would be rapids when the water was flowing, and then, on a turn, they came to the rocky dip of a high waterfall. Frozen it was still, of course. One mass of ice and snow. Rather a terrible place in the strange stillness of its hold-up. And everywhere rocks--rocks and steep, difficult places blending with the forest. ”

“ Pressing onward up the gently ascending slope, we came at length to a gap in the mountains bordered on the north by a towering cliff fully a thousand feet high, and were rejoiced to find that the snow surface on the opposite side of the divide inclined westward with a grade as gentle as the one we had ascended. Looking far down the western snow-slope, we could see where it joined a large glacier flowing southward past the end of the great cliffs which extended westward from the divide. ”

“ Nothing moves, slides, stirs, or bends; all is inflexible and fixed. The very trees, loaded with piled-up masses of snow, stand like things of steel pinned motionless against the background of running slope or blue-black sky. ”

“ Each one of us grasped the cordage which held the cushions together, and the rapidity of the motion forced us almost to hold our breath.
Down the smooth, white slope we sped as a bird skims through the air. It seemed to me as if we passed over miles and miles of snow. Sometimes my face was turned down the mountain where the snow surface seemed to stretch out illimitably, and then it was turned upward towards the apparently illimitable slopes over which we had passed. ”

“ The inclination of a hanging slope of snow always appears still more exaggerated as seen from in front if it lies on the face of what is mainly a rock peak. We have in such case to discover if the snow is lying on ice, or only forms a coating to the rock. If it is on ice, the lower edge of the slopes, where the snow runs out on to the rock, will generally betray a rim or broken wall of ice. To judge of the quality of such a snow surface, and of the strength of its attachment to its ice or rock sub-surface, the slopes below it must be examined, and snow, stone or water furrows looked for. ”

“ And among the high mountains the slopes are often, as you know, very steep. When snow gathers deeply on sloping ground, there comes a time when the force of gravity overcomes the tendency of the pressed snow to remain where it is, and then the snow begins to slide slowly down the slope. From one slope it passes on downward to the next, joined continually by other sliding masses from neighboring slopes until they all unite into one long tongue which creeps slowly down some valley to a point where it melts. This tongue from the snow-fields is the glacier. ”

“ For when about a quarter of the height has been ascended, the first flight, as it were, up to the snow drift, the traveller looking above him, puffing and panting with his violent efforts, sees above him what appears to be the summit close at hand, which is but the top of the lower ridge, from which runs a somewhat level path on the slope to the snow drift—an enormous mass of snow, some half-mile long, and, I suppose, from one to two hundred yards broad, and, I fancy, from fifty to a hundred feet deep, filling a gorge of the mountain which commences quite at the summit. ”

“ As the hard snow slopes were mostly much too steep to climb, without resorting to the tedious expedient of cutting steps with an ice-axe, we kept as much as possible to the rocky arêtes. Occasionally, however, the arête would terminate upwards in a large snow slope, and in such cases we cut steps across the névé to any arête which seemed to persist for some length in an upward direction. ”

“ At three o’clock we got to the head of the snow slope before mentioned, and found it to be in a most dangerous condition, with hard ice eight inches from the surface. We now decided to take advantage of the warm rocks, on which we might have a spell, and perhaps a sleep, until the snow became firmer, when we would be able to proceed with greater ease as the sun went down. Graham and I volunteered to cut steps down the slope, while the others, who complained of not having had enough sleep, might stay on the rocks, enjoy a spell, and join us at the bottom. ”

“ The wind plays strange pranks with snow; snow is the most plastic medium it has to mould into images and symbols of its moods. Here one of these promontories would slope down, and the very next one would slope upward as it advanced across the open space. In every case there had been two walls, as it were, of furious blow, and between the two a lane of comparative calm, caused by the shelter of a clump of brush or weeds, in which the snow had taken refuge from the wind’s rough and savage play. ”

“ From this place they could see it slowly creeping down the long slope towards another precipice, and where, when it reached the brink, it fell over in another cataract, producing another long peal of thunder, which, being repeated by the echoes of the mountains and rocks around, filled the whole heavens with its rolling reverberations. In this manner the mass of ice and snow went down slope after slope and over precipice after precipice, till at length it made its final plunge into the great chasm at the foot of the mountain and disappeared from view. ”

“ We were able to struggle on without regarding dangers, half-dazed with the heat and the glare and with mere fatigue, occasionally encouraged by a glimpse of the skyline above us, a clean edge of snow where the angle set back to the pass, more often enveloped in the scorching mist which made with the snow a continuous whiteness, so that the smooth slope, even so near as where the foot must be placed next, was usually indistinguishable. ”

“ From this position the last man could in an instant have been down the slope to his right, and have held us with the greatest ease.
We advanced a yard or two further, and then the entire surface upon which we stood commenced to move! A moment more and we were struggling for our lives, dashing our axes through the rushing snow, and endeavouring to arrest our wild career, which, unless checked at once, would cause us to be precipitated down the entire face of the mountain, to the glacier below. Then it was that the firm bed of snow beneath the newer layer stood us in good stead. ”

“ Proceeding carefully up the snow-slope, we crossed to the right and following the ridge, which one of the guides had traversed some weeks before, had some good rock climbing. In some place the foot-holds were rendered easier by the hard snow, particularly on a narrow ledge skirting the right shoulder of the mountain near the top; but elsewhere the rocks were unpleasantly slippery through melting snow. ”

“ The loose snow was shovelled away and the steps dug in the hard snow beneath, and the creepers upon our feet gave good grip in it. Thus, slowly, step by step, we descended the ridge and in an hour and a half had reached the cleavage, [Pg 124] the most critical place in the whole descent. With the least possible motion of the feet, setting them exactly in the shovelled steps, we crept like cats across this slope, thrusting the points of our axes into the holes that had been made in the ice-wall above, moving all together, the rope always taut, no one speaking a word. ”

“ I have always escaped the snow slide, I always test the snow as I go. If I get on a slope where Snowslides are frequent I prod deep into the snow to ascertain its actual depth, where the snow is thick it is most apt to slide. The cry is keep close to the rocks and you are safe. After many days of severe suffering and fighting cold we came to a perpendicular ridge of ice which we discovered was a long ridge, there seemed to be no way around so we prepared to let over each other. ”

“ There is also the final test of touch, which is made on the spot, before any snow slope is traversed. The change in the condition of the snow, which may be produced by a day of sun before we can return down the slope, must not be left out of the calculation. Many slopes whose surface may be adjudged and found safe for passage in the early morning cannot be trusted by nightfall. ”

“ To have an idea of our situation, you must imagine us marching in single file on the steep mountain side, placing with the greatest care our feet in the steps, which the hardness of the snow rendered it necessary for our leader to cut with an axe, supporting ourselves with our poles against the upper side of the slope, and having on the other side, the same rapid slope terminating below in a precipice several hundred feet in height, over which we saw rapidly hurried all the small pieces of ice, that we loosened with our feet. ”

“ All the minor ridges and valleys are levelled and concealed under a general covering of snow, but here and there some steep mountains protrude abruptly from the icy slope, and a few superficial lines of stones or moraines are visible at certain seasons, when no snow has fallen for many months, and when evaporation, promoted by the wind and sun, has caused much of the upper snow to disappear. ”

“ I am aware that all authorities agree in preferring ice to incoherent snow, but when the ice slope is measured by hundreds of feet, and when the northern couloir of the "Lion," swept by the afternoon avalanches, is below, I will frankly confess that any snow, however bad, is a delight, and its treacherous aid most thankfully accepted. ”

“ Of the snow, the greater mass lay on that slope directly nearest us, covering the slope wherever its inclination was not too great. The largest bed of snow would cover a space measuring about 600 by 300 feet, and of such a depth that in only two spots did the black rock crop out above its surface. ”

“ On the upper glacier where the slope becomes steep, the ascent is made over fields of ice and snow and ledges of glaciated rock to vantage points along- side and above the rugged and picturesque ice-fall. ”

“ Slopes of a certain angle and conformation.
6. Differences of density, moisture, and consistency in superposed layers of snow.
A study of the statics of snow is the royal road to the understanding of avalanches.
On a slope snow is in a state of more or less pronounced instability.
A first fall of dry winter snow upon dry slopes is extremely avalanchy, provided it be heavy enough. If it be a fall of wet snow on a porous surface—that is, neither frozen ground nor hard rock—the snow will as it were flop together in a slithering mass, but is not likely to form itself into a dangerous compact floe. ”

“ My guide continually admonished me to make my footing sure, and to fix at each step my staff firmly in the consolidated snow. At one place, for a short steep ascent, the slope became hard ice, and our position a very ticklish one. We hewed our steps as we moved upward, but were soon glad to deviate from the ice to a position scarcely less awkward. The wind had so acted upon the snow as to fold it over the edge of the kamm, thus causing it to form a kind of cornice, which overhung the precipice on the Lyskamm side of the mountain. ”

“ This action of the wind, denuding the exposed ridges and feeding the hollows and lee-sides, takes place on both a large and a small scale: on a large scale, when snowy valleys are fed from the snow blown off the exposed ridges that rise out of them, and on a small scale on any slope exposed to wind which is divided by ridges, however small. Any tributary ridge on a slope across which a wind is blowing will have a wind-side and a lee-side, and will accumulate snow on the lee-side and give off snow on the wind-side. ”

“ But in the zone of variable temperature, where the summer melts the surface of the snows which winter had collected, the snowy mass becomes first bathed with water, and afterwards more or less consolidated by frost; it becomes in fact nevé, and, pressed downwards by gravity, begins to glide on its bed, or on surfaces of separation formed within itself, more or less parallel to the local slope of the valley. As we descend below the limit of perpetual snow, the ground, growing warmer, maintains fluidity below the glacier [2] , the descent of which thus becomes less impeded. ”

“ If on account of the nature of the ground you decide to run straight down a steep slope instead of taking it in zigzags, you must, of course, be ready to drop into Telemark position for any sudden undulations or difficult snow.
Remember that the quality of the snow depends to a great extent on the direction in which the slope faces.
On slopes with a north aspect, especially if they are steep, the snow gets little or no sun, and is generally soft and easy, though even here it may sometimes get crusted by very strong winds or by frost after a warm wind or rain. ”

“ At the upper termination of nearly all highly situated ice slopes there almost invariably occurs between the rocks above, or between the ice slope and the permanent clinging ice above, a large gap or crevasse, partially filled or bridged with new snow during the winter months, but more open as the warmth of spring and summer causes the snow to melt and the ice to shrink away. ”

“ When a sufficient depth of snow collects upon the earth's surface, the lower portions are squeezed out by the pressure of the superincumbent mass. If it rests upon a slope it will yield principally in the direction of the slope, and move downwards.
5. In addition to this, the whole mass slides bodily along its inclined bed, and leaves the traces of its sliding on the rocks over which it passes, grinding off their asperities, and marking them with grooves and scratches in the direction of the motion. ”

“ The cold, foggy clouds are hiding the summits and will soon envelop the spot where we stand. We go down by a different path, but over almost continuous snow-fields, for more than two miles. The return is much easier than the ascent, although if one lost his footing upon some steep slope, it would mean a long slide or tumble. The solid earth is reached without accident. ”