"A loud peal of thunder was heard; and shortly after I observed that a strange singing sound, like that of a kettle, was issuing from my alpenstock. We halted, and finding that all the axes and stocks emitted the same sound, stuck them into the snow. The guide from the hotel now pulled off his cap, shouting that his head burned; and his hair was seen to have a similar appearance to that which it would have presented had he been on an insulated stool under a powerful electrical machine. We all of us experienced the sensation of pricking and burning in some part of the body, more especially in the head and face, my hair also standing on end in an uncomfortable but very amusing manner. The snow gave out a hissing sound, as though a heavy shower of hail were falling; the veil on the wide-awake of one of the party stood upright in the air; and on waving our hands, the singing sound issued loudly from the fingers. Whenever a peal of thunder was heard, the phenomenon ceased, to be resumed before its echoes died away. At these times we felt shocks, more or less violent, in those portions of the body which were most affected. By one of these shocks my right arm was paralysed so completely that I could neither use nor raise it for several minutes, nor indeed until it had been severely rubbed; and I suffered much pain in it at the shoulder-joint for some hours."
The successive layers of snow which fall on the mountains do not remain there for ever. Unless got rid of in some way their thickness would mount up to an enormous extent. It is reckoned that on the Alps the average yearly fall of snow is thirty-three feet. In the course of a century, therefore, the height of these mountains would be increased by 3,300 feet, which we know is not the case. Various causes prevent its accumulating, among which we may mention the powerful influence of the sun's rays, the evaporation promoted by the atmosphere, the thawing influence of rain and mist, avalanches, and lastly, which is perhaps the most important, the fact that the snow composing the snowfields, as they are called, of the high regions slowly creeps down towards the valleys, where they move along as glaciers, the ends of which are gradually melted away by the warm air surrounding them, and thus the muddy glacier-streams are originated. Few perils are more dreaded by the inhabitant of the Alps than those of the avalanches. The particular way in which each avalanche descends is varied according to the shape of the mountain, the condition of the snow, and the time of the year. Hence there are three different kinds of avalanche. First, there is the ice-avalanche. The smaller glaciers, which, in the Alps, cling to the upper slopes of the higher mountains, frequently terminate abruptly on the edge of some precipice. Thus the ice, urged on by the pressure of the masses above it, moves forward until it plunges over and falls into the abyss below. Large portions break off; and these, as they bound down the cliffs, are dashed into countless pieces, which leap from crag to crag high into the air: now the falling mass, like some swollen torrent, dashes with sullen roar through a gully, now, emerging, crashes over a precipice, or spreads itself out like a fan, as it hisses down a snow-slope. These avalanches expend their force in the higher regions, and are harmless, unless any one happens to be crossing their track at the time; but accidents from this source can generally be avoided. In the distance the avalanches look like waterfalls of the purest foam, but when approached are found to be composed of fragments of ice of every size, from one, two, or more cubic yards down to tiny little balls. In spring and summer, when the white layers, softened by the heat, are falling away every hour from the lofty summits of the Alps, the pedestrian, taking up a position on some adjacent headland, may watch these sudden cataracts dashing down into the gorges from the heights of the shining peaks. Year after year travellers seated at their ease on the grassy banks of the Wengern Alp have watched with pleasure the avalanches rolling to the base of the silvery pyramid of the Jungfrau. First, the mass of ice is seen to plunge forth like a cataract, and lose itself in the lower parts of the mountain; whirlwinds of powdered snow, like clouds of bright smoke, rise far and wide into the air; and then, when the cloud has passed away, and the region has again assumed its solemn calm, the thunder of the avalanche is suddenly heard reverberating in deep echoes in the mountain gorges, as if it were the voice of the mountain itself.
The other two kinds of avalanche are composed of snow. The dust-avalanche usually falls in winter-time, when the mountains are covered deep with fresh-fallen snow. Such masses of snow, not yet compacted into ice, rest insecurely upon the icy slopes, and hang in festoons and curtains over the peaks, or lie on smooth banks of pasture, until some accident, such as a gust of wind, breaks the spell, and the whole mass slides down into the valley below. These avalanches are accompanied by fearful blasts of wind which work dire destruction. Almost the whole village of Leukerbad was destroyed by one of these on the 14th of January, 1719, and fifty-five persons perished. In 1749, more than one hundred persons were killed in the village of Ruaras (Grisons), which during the night was overwhelmed by an avalanche. So silently were some of the houses buried that the inhabitants, on waking in the morning, could not conceive why the day did not dawn. It is said, though it seems almost incredible, that in the time of the Suabian War, in the year 1498, one of these avalanches swept four hundred soldiers over a cliff, and they all escaped without serious injury.
The army of General Macdonald, in his celebrated passage of the Splügen in December, 1800, suffered severely from these dust-avalanches. A troupe of horse was completely cut through while on the march; and thirty dragoons were precipitated into a gulf below the road, where they all perished. And again, some days afterwards, in descending a gorge, the columns were repeatedly severed by avalanches; and more than one hundred soldiers, with a number of horses and mules, were lost. On one of these occasions the drummer of a regiment was carried away; and it is said that they heard him beating his drum in the gorge below, in the hope that his comrades would come to his rescue. Help, however, was out of the question. The sounds gradually became fainter, and the poor lad must have perished in the cold.
The ground-avalanches are different from those just described, consisting of dense and almost solid masses of snow which have lain for a long time exposed to atmospheric influences. They are much heavier than the dust-avalanches, and therefore more destructive; so that the inhabitants take great pains to protect themselves from this source of danger. Thickly planted trees are the best protection against avalanches of every kind. Snow which has fallen in a wood cannot very well shift its place; and when masses of snow descend from the slopes above, they are unable to break through so strong a barrier. Small shrubs, such as rhododendrons, or even heaths and meadow-grass, are often sufficient to prevent the slipping of the snow; and therefore it is very imprudent not to allow them to grow freely on mountain-slopes. But it is still more dangerous to cut down protecting forests, or even to do so partly. This was illustrated by the case of a mountain in the Pyrenees, in the lofty valley of Neste; after it had been partially cleared of trees, a tremendous avalanche fell down in 1846, and in its fall swept away more than fifteen thousand fir-trees.
The Swiss records tell us what a terrible scourge the avalanche can be in villages which in summer-time appear such calm and happy scenes of pastoral life. M. Joanne, in the introduction to his valuable "Itinéraire de la Suisse"[13] gives a list of twelve of the most destructive avalanches that have fallen in Switzerland. In old days they seem to have been as great a source of danger as in modern times. Thus we find that in the year 1500, a caravan of six hundred persons was swept away in crossing the Great St. Bernard; three hundred were buried under an avalanche which fell from Monte Cassedra (Ticino). Another one in the year 1720, at Obergestelen, in the Rhone Valley, destroyed one hundred and twenty cottages, four hundred head of cattle, and eighty-eight persons. The bodies were buried in a large pit in the village cemetery, on the wall of which was engraved the following pathetic inscription: "O God, what sorrow!—eighty-eight in a single grave!" ("Gott, welche Trauer!—acht und achtzig in einem Grab!")
It is a curious fact that animals have a wonderful power of anticipating coming catastrophes. When human beings are unaware of danger, they are often warned by the behaviour of animals. Country people sometimes say that they can tell from the birds when the weather is about to change; and there is little doubt but that sea-gulls come inland before rough, stormy weather. But in the case of earthquakes the behaviour of birds, beasts, and even fishes is very striking. It is said that before an earthquake rats, mice, moles, lizards, and serpents frequently come out of their holes, and hasten hither and thither as if smitten with terror. At Naples, it is said that the ants quitted their underground passages some hours before the earthquake of July 26, 1805; that grasshoppers crossed the town in order to reach the coast; and that the fish approached the shore in shoals. Avalanches, it is well known, produce tremors similar to those due to slight earthquake shocks; and there are many stories in Switzerland of the behaviour of animals just before the catastrophe takes place. Berlepsch relates that a pack-horse on the Scaletta Pass, which was always most steady, became restive when an avalanche was coming; so that he was valuable to his owners in bad weather. One day, when near the summit of the pass, he suddenly stopped. They foolishly took no notice of his warning this time; but he presently darted off at full speed. In a few seconds the avalanche came and buried the whole party.
If these stories can be relied upon, it would seem that animals are either more sensitive to very slight tremors of the earth, or else that they are more on the lookout than human beings. Perhaps North American Indians have learned from animals in this respect, for they can tell of a coming enemy on the march by putting their ears to the ground and listening.
But there are worse dangers in the mountains than falls of snow and ice, for sometimes masses of rock come hurtling down, or worse still, the whole side of a mountain gives way and spreads ruin far and wide. Perpendicular or overhanging rocks, which seem securely fastened, suddenly become detached and rush headlong down the mountain-side. In their rapid fall, they raise a cloud of dust like the ashes vomited forth by a volcano; a horrible darkness is spread over a once pleasant valley; and the unfortunate inhabitants, unable to see what is taking place, are only aware of the trembling of the ground, and the crashing din of the rocks as they strike together and shatter one another in pieces. When the cloud of dust is cleared away, nothing but heaps of stones and rubbish are to be seen where pastures once grew, or the peasant ploughed his acres in peace. The stream flowing down the valley is obstructed in its course, and changed into a muddy lake; the rampart of rocks from which some débris still comes crumbling down has lost its old form; the sharpened edges point out the denuded cliff from which a large part of the mountain has broken away. In the Pyrenees, Alps, and other important ranges there are but few valleys where one cannot see the confused heaps of fallen rocks.
Many of these catastrophes, known as the "Bergfall," have been recorded; and the records tell of the fearful havoc and destruction to life and property due to this cause. In Italy the ancient Roman town of Velleja was buried, about the fourth century, by the downfall of the mountain of Rovinazzo; and the large quantity of bones and coins that have been found proves that the fall was so sudden that the inhabitants had no time to escape.