Part 10 (1/2)
I have already noticed the colour of the fresh snow upon the summit of the Stelvio pa.s.s. Since I observed it there it has been my custom to pay some attention to this point at all great elevations. This morning, as I ascended Monte Rosa, I often examined the holes made in the snow by our batons, but the light which issued from them was scarcely perceptibly blue. Now, however, a deep layer of fresh snow overspread the mountain, and the effect was magnificent. Along the kamm I was continually surprised and delighted by the blue gleams which issued from the broken or perforated stratum of new snow; each hole made by the staff was filled with a light as pure, and nearly as deep, as that of the unclouded firmament. When we reached the bottom of the kamm, Lauener came to the front, and tramped before me. As his feet rose out of the snow, and shook the latter off in fragments, sudden and wonderful gleams of blue light flashed from them. Doubtless the blue of the sky has much to do with mountain colouring, but in the present instance not only was there no blue sky, but the air was so thick with fog and descending snow-flakes, that we could not see twenty yards in advance of us. A thick fog, which wrapped the mountain quite closely, now added its gloom to the obscurity caused by the falling snow. Before we reached the base of the mountain the fog became thin, and the sun shone through it. There was not a breath of air stirring, and, though we stood ankle-deep in snow, the heat surpa.s.sed anything of the kind I had ever felt: it was the dead suffocating warmth of the interior of an oven, which encompa.s.sed us on all sides, and from which there seemed no escape. Our own motion through the air, however, cooled us considerably. We found the snow-bridges softer than in the morning, and consequently needing more caution; but we encountered no real difficulty among them. Indeed it is amusing to observe the indifference with which a snow-roof is often broken through, and a traveller immersed to the waist in the jaws of a fissure. The effort at recovery is instantaneous; half instinctively hands and knees are driven into the snow, and rescue is immediate. Fair glacier work was now before us; after which we reached the opposite mountain-slope, which we ascended, and then went down the flank of the Riffelberg to our hotel. The excursion occupied us eleven and a half hours.
FOOTNOTES:
[A] My staff was always the handle of an axe an inch or two longer than an ordinary walking-stick.
(19.)
On the afternoon of the 11th I made an attempt alone to ascend the Riffelhorn, and attained a considerable height; but I attacked it from the wrong side, and the fading light forced me to retreat. I found some agreeable people at the hotel on my return. One clergyman especially, with a clear complexion, good digestion, and bad lungs--of free, hearty, and genial manner--made himself extremely pleasant to us all. He appeared to bubble over with enjoyment, and with him and others on the morning of the 13th I walked to the Gorner Grat, as it lay on the way to my work. We had a glorious prospect from the summit: indeed the a.s.semblage of mountains, snow, and ice, here within view is perhaps without a rival in the world.[A] I shouldered my axe, and saying ”good-bye” moved away from my companions.
”Are you going?” exclaimed the clergyman. ”Give me one grasp of your hand before we part.”
This was the signal for a grasp all round; and the hearty human kindness which thus showed itself contributed that day to make my work pleasant to me.
[Sidenote: A DIFFICULT DESCENT. 1858.]
We proceeded along the ridge of the Rothe k.u.mme to a point which commanded a fine view of the glacier. The ice had been over these heights in ages past, for, although lichens covered the surfaces of the old rocks, they did not disguise the grooves and scratchings. The surface of the glacier was now about a thousand feet below us, and this it was our desire to attain. To reach it we had to descend a succession of precipices, which in general were weathered and rugged, but here and there, where the rock was durable, were fluted and grooved. Once or twice indeed we had nothing to cling to but the little ridges thus formed. We had to squeeze ourselves through narrow fissures, and often to get round overhanging ledges, where our main trust was in our feet, but where these had only ledges an inch or so in width to rest upon.
These cases were to me the most unpleasant of all, for they compelled the arms to take a position which, if the footing gave way, would necessitate a _wrench_, for which I entertain considerable abhorrence.
We came at length to a gorge by which the mountain is rent from top to bottom, and into which we endeavoured to descend. We worked along its rim for a time, but found its smooth faces too deep. We retreated; Lauener struck into another track, and while he tested it I sat down near some gra.s.s tufts, which flourished on one of the ledges, and found the temperature to be as follows:--
Temperature of rock 42 C.
Of air an inch above the rock 32 Of air a foot from rock 22 Of gra.s.s 25
The first of these numbers does not fairly represent the temperature of the rock, as the thermometer could be in contact with it only at one side at a time. It was differences such as these between gra.s.s and stone, producing a mixed atmosphere of different densities, that weakened the sound of the falls of the Orinoco, as observed and explained by Humboldt.
[Sidenote: SINGULAR ICE-CAVE. 1858.]
By a process of ”trial and error” we at length reached the ice, after two hours had been spent in the effort to disentangle ourselves from the crags. The glacier is forcibly thrust at this place against the projecting base of the mountain, and the structure of the ice correspondingly developed. Creva.s.ses also intersect the ice, and the blue veins cross them at right angles. I ascended the glacier to a region where the ice was compressed and greatly contorted, and thought that in some cases I could see the veins crossing the lines of stratification. Once my guide drew my attention to what he called ”_ein sonderbares Loch_.” On one of the slopes an archway was formed which appeared to lead into the body of the glacier. We entered it, and explored the cavern to its end. The walls were of transparent blue ice, singularly free from air-bubbles; but where the roof of the cavern was thin enough to allow the sun to s.h.i.+ne feebly through it, the transmitted light was of a pink colour. My guide expressed himself surprised at ”_den rothlichen Schein_.” At one place a plate of ice had been placed like a ceiling across the cavern; but owing to lateral squeezing it had been broken so as to form a V. I found some air-bubbles in this ice, and in all cases they were a.s.sociated with blebs of water. A portion of the ”ceiling,” indeed, was very full of bubbles, and was at some places reduced, by internal liquefaction, to a mere skeleton of ice, with water-cells between its walls.
[Sidenote: STRUCTURE AND STRATA. 1858.]
High up the glacier (towards the old Weissthor) the horizontal stratification is everywhere beautifully shown. I drew my guide's attention to it, and he made the remark that the perfection of the lower ice was due to the pressure of the layers above it. ”The snow by degrees compressed itself to glacier.” As we approached one of the tributaries on the Monte Rosa side, where great pressure came into play, the stratification appeared to yield and the true structure to cross it at those places where it had yielded most. As the place of greatest pressure was approached, the bedding disappeared more and more, and a clear vertical structure was finally revealed.
FOOTNOTES:
[A] In 1858 Mr. E. W. Cooke made a pencil-sketch of this splendid panorama, which is the best and truest that I have yet seen.
THE GoRNER GRAT AND THE RIFFELHORN. MAGNETIC PHENOMENA.
(20.)
At an early hour on Sat.u.r.day, the 14th of August, I heard the servant exclaim, ”_Das Wetter ist wunderschon!_” which good news caused me to spring from my bed and prepare to meet the morn. The range of summits at the opposite side of the valley of St. Nicholas was at first quite clear, but as the sun ascended light c.u.muli formed round them, increasing in density up to a certain point; below these clouds the air of the valley was transparent; above them the air of heaven was still more so; and thus they swung midway between heaven and earth, ranging themselves in a level line along the necks of the mountains.
[Sidenote: GENERATION OF CLOUDS. 1858.]
It might be supposed that the presence of the sun heating the air would tend to keep it more transparent, by increasing its capacity to dissolve all visible cloud; and this indeed is the true action of the sun. But it is not the only action. His rays, as he climbed the eastern heaven, shot more and more deeply into the valley of St. Nicholas, the moisture of which rose as invisible vapour, remaining unseen as long as the air possessed sufficient warmth to keep it in the vaporous state. High up, however, the cold crags which had lost their heat by radiation the night before, acted like condensers upon the ascending vapour, and caused it to curdle into visible fog. The current, however, continued ascensional, and the clouds were slowly lifted above the tallest peaks, where they arranged themselves in fantastic forms, s.h.i.+fting and changing shape as they gradually melted away. One peak stood like a field-officer with his cap raised above his head, others sent straggling cloud-balloons upwards; but on watching these outliers they were gradually seen to disappear. At first they shone like snow in the sunlight, but as they became more attenuated they changed colour, pa.s.sing through a dull red to a dusky purple hue, until finally they left no trace of their existence.