Almost all the tops of the highest mountains are bare and pointed; which proceeds from their being continually assaulted by storms and tempests. All the earthy substances with which they might have been once covered, have for ages been washed away from their summits; and nothing is left but immense rocks, which no tempest has hitherto been able to destroy. Nevertheless, time is every day making depredations, and huge fragments are seen tumbling down the precipices, either loosened from their summits by the rains and frost, or struck down by lightning. Nothing can exhibit a more terrible picture than one of these enormous masses, commonly larger than a house, falling from its height, and rolling down the side of the mountain with a noise louder than thunder. Dr. Plot tells us of one in particular, which being loosened from its bed, rolled down the precipice, and was partly shattered into a thousand pieces. One of the largest fragments, however, still preserving its motion, travelled over the plain below, crossed a rivulet in the midst, and at last stopped on the other side of the bank! These fragments are often struck off by lightning, and sometimes undermined by rains; but the most usual manner in which they are disunited from the mountain is by frost: the rains first insinuate and find their way between the interstices of the mountain, and continue there until by the intense cold they are converted into ice, when the water swells with an irresistible force, and produces the same effect as gunpowder, splitting the most solid rocks, and thus shattering their summits. Sometimes whole mountains are, by various causes, disunited from each other. In many parts of the Alps, there are amazing clefts, the sides of which so exactly correspond with the opposite, that no doubt can be entertained of their having been once joined. At Cajeta, in Italy, a mountain was split in this manner by an earthquake; and there is a passage opened through it, that appears as if done by the industry of man.

In the Andes these breaches are often seen. That at Thermopylae in Greece has been long famous. The mountain of the Troglodytes in Arabia has thus a passage through it; and that in the late duchy of Savoy, which Nature began, and which Victor Amadeus completed, is an instance of the same kind, "In June, 1714, a part of the mountain of Dia-bleret, in the district of Valais, in France, suddenly fell down, between two and three p. m. the weather being very calm and serene. This mountain, which was of a conical figure, destroyed fifty-five cottages in its fall. Fifteen persons, with about one hundred beasts, were also crushed beneath its ruins, which covered an extent of ground of a league square. The dust it occasioned instantly enveloped all the neighbourhood in darkness. The heaps of rubbish were more than three hundred feet high. They stopped the current of a river that ran along the plain, which now is formed into several new and deep lakes. There appeared, through the whole of this rubbish, none of those substances that seemed to indicate that this catastrophe had been occasioned by means of subterraneous fires. Most probably, the base of this rocky mountain had been decomposing through the lapse of many ages, and thus fell without any extraneous violence."

In 1618, the town of Fleurs, in France, was buried beneath a rocky mountain, at the foot of which it was situated. Such accidents are produced by various causes : by earthquakes; by being decayed at the bottom; or by the foundation of one part of the mountain being hollowed by waters, and, thus wanting a support, breaking from the other. Thus it generally has been found in the great chasms in the Alps; and it is almost always the case in those disruptions of hills, called land-slips: these are nothing more than the sliding down of a higher piece of ground, driven from its situation by subterraneous inundations, and settling upon the plain below. There is not an appearance in nature that so much astonished our ancestors as these land-slips. To behold a large upland, with its houses, corn, and cattle, at once loosened from its place, and floating as it were upon the subjacent water, - to see it quitting its ancient situation, and sailing forward like a ship, - is certainly one of the most extraordinary appearances that can be imagined, and, to a people ignorant of the powers of nature, might well be considered as a prodigy. Accordingly, we find all our old historians mentioning it as an omen of approaching calamities. In this more enlightened age, however, its cause is well known; and, instead of exciting ominous apprehensions in the populace, it only gives rise to some very ridiculous law-suits among the several claimants, whose the property thus divided from its kindred soil shall be; whether the land shall belong to the original pos sessor, or to him upon whose grounds it has encroached and settled.

In the lands of Hatberg, in Ireland, there stood a declivity gradually ascending for nearly half a mile. On the 10th of March, 1713, the inhabitants perceived a crack on its side, like a furrow made with a plough, which they imputed to the effects of lightning as there had been a thunder-storm the night before. However, on the evening of the same day, they were surprised to hear a hideous confused noise issuing all around from the side of the hill; and their curiosity being awakened, they resorted to the place. There, to their amazement, they found an extent of ground, of nearly five acres, all in gentle motion, and sliding down the hill upon the subjacent plain. This motion, together with the noise, continued the remaining part of the day, and the whole of the following night; the noise proceeding, probably, from the attrition of the ground beneath. The day following, this strange journey down the hill ceased ; and above an acre of the meadow below was found covered with what before composed a part of the declivity. But such tremendous land-slips, when a whole mountain's side descends, happen very rarely.

There are some of another kind, however, much more common; and as they are always sudden, much more dangerous. These are snow-slips, or avalanches, well known, and greatly dreaded by travellers. They are justly described in the following beautiful lines of one of our poets:By an hundred winters piled, Where the glaciers, dark with death, Hang o'er precipices wild, Hang suspended by a breath.

If a pulse but throb alarm, Headlong down the steeps they fall; For a pulse will break the charm, Bounding, bursting, burying all.

It often happens, that when snow has long been accumulated on the tops and on the sides of mountains, it is borne down the precipice either by tempests, or by its own melting. At first, when loosened, the volume in motion is but small, but it gathers as it continues to roll; and by the time it has reached the habitable parts of the mountain, it is generally grown to an enormous bulk. Wherever it rolls, it levels all things in its way, or buries them in unavoidable destruction. Instead of rolling, it sometimes is found to slide along from the top; yet even thus, it is generally fatal. Nevertheless, we had an instance a few years ago, of a small family in Germany, that lived for above a fortnight under one of these snow-slips. Although they were buried during the whole of that time in utter darkness, and under a bed of some hundreds of feet deep, yet they were providentially taken out alive ; the weight of the snow being supported by a beam that kept up the roof, and nourishment supplied to them by the milk of a she-goat, that was buried under the same ruin.