the coast rose upwards of twenty feet during the terrible disturbance of 1538, reducing the Lucrine lake to its present shallowness, and causing the sea to retreat from its former limit. But evidence exists of repeated changes of level along this coast, which has rendered it one of the most interesting and valuable regions to the geologist. Upon the shore near Pozzuoli, there are three remaining pillars of an ancient building, commonly called the Temple of Serapis, though antiquaries differ considerably respecting its character. The pillars exhibit unequivocal signs of having once, and for a long period, been immersed in the waves, exhibiting marks of the dactylides, a species of shell-fish which burrows in the stone. The lower and upper parts of the columns are uninjured, the former having been protected by accumulations of rubbish, and the latter having been above the level of the water; but a zone in the middle, twelve feet in height, is every where pierced by marine perforating bivalves. "The holes of these animals are pear-shaped, the external opening being minute, and gradually increasing downwards. At the bottom of the cavities, many shells are still found, notwithstanding the great numbers that have been taken out by visitors. The perforations are so considerable in depth and size, that they manifest a long-continued abode of the lithodomi in the columns; for as the inhabitant grows older, and increases in size, it bores a larger cavity, to correspond with the increasing magnitude of its shell. We must consequently infer a long-continued immersion of the pillars in sea-water, at a time when the lower part was covered up and protected by strata of tuff and the rubbish of buildings, the highest part at the same time projecting above the waters, and being consequently weathered, but not materially injured." It thus seems to be settled, almost to demonstration, that the floor of this temple or building, of course originally placed upon a site above the reach of the sea, has subsided so as to have sunk below the level of its waters, and afterwards been elevated again—an oscillation shared by the adjacent district. Captain Hall was shown, near the remains of an amphitheatre, what are called the ruins of Cicero's Villa-a mass of rubbish upon the dry land at the foot of the cliff, considerably above the present level of the sea, the guide describing the orator as having fished out of his parlour window. However doubtful the identity of the spot, it is perfectly possible for such a fact to have transpired; and, as the narrator observes, the gossip of the guide shows the established belief, and carries with it great interest, as corroborating the supposition that the ground has been raised by the volcanic forces which we know to be in action in that quarter. Loffredo, writing in 1580, is quoted by Mr. Lyell as affirming that, fifty years previously, the sea washed the base of the hills which rise from the level strip of land before alluded to, and expressly stating that a person "might have fished" then from the site of the ruins of the amphitheatre. An elevation of the coast transpired upon a grand scale during the great Chilian earthquake in 1822, so well described by Mrs. Graham, who was then a resident in that country. Upon the night of its occurrence, attracted by the fineness of the evening, she had been sitting in her verandah, watching the lightning which played uninterruptedly over the Andes till after dark, when a delightful calm moonlight night followed a quiet and moderately warm day. It was so pleasant, that she quitted the verandah with regret, and returned into the house, where she sat quietly conversing with her friends till about a quarter past ten, when they were all sensible of a violent shock, and heard a noise like the explosion of a mine. One of the party started up, exclaiming, "An earthquake! an earthquake!" and ran out of the house; but another -a connexion of the relatorin delicate health, and unfit to be exposed to the night air, and she, unwilling to leave him, remained. In a little time the motion of the earth, increasing, threw down the chimneys, and the walls of the house opened. The urgency of the danger now overcame lesser fears, and every body fled for refuge to the lawn. In a few minutes, the quick was vibration of the earth was changed to a rolling motion, like that of a ship at sea. Though there was not a breath of air, yet the trees were so agitated, that their topmost branches seemed on the point of touching the ground. The lowing of the frighted cattle, and the screaming of the sea-fowl, never ceased till the morning; while the rational witnesses of this awful convulsion of nature experienced, in its full extent, a sensation which only those who have felt it can entirely conceive- the certainty of great and sudden danger, which no exertion can avert or mitigate. Though they fled from the falling house, who could assure them that the next moment the ground would not open beneath their feet? The shock of this earthquake was felt throughout a tract of country extending 1200 miles from north to south. St. Jago. Valparaiso, and some other towns were much injured; but the chief peculiarity of the event was, that at Valparaiso the shore was found to have been lifted up three feet above its former level; and, on further examination, it appeared that the whole coast, for above one hundred miles, had been elevated in the same manner. Part of the bed of the sea was also raised, and remained bare and dry at high water, with beds of oysters, muscles, and other shell-fish adhering to the rocks on which they grew. The fish were all dead, and exhaled an offensive smell. Conical mounds of earth, about four feet high, were thrown up in several districts, by the forcing up of water mixed with sand, through funnel-shaped hollows. The whole extent of country lifted up above its former level was estimated at 100,000 square miles. The whole surface, from the foot of the Andes to a great distance under the sea, is supposed to have been raised, so that the soundings in the harbour of Valparaiso were in consequence materially altered, the depth of water being much less than before. In the course of a few hours the change of level was effected; but the shocks continued from November 1822 to September 1823, and even then two days seldom passed without one being experienced, and sometimes two or three were felt during twenty-four hours. After this earthquake, Mrs. Graham observed, that besides the beach newly raised above high-water mark, there were several more ancient lines of beach, one above another, consisting of shingle mixed with shells, and extending along the shore in parallel lines, the uppermost being fifty feet above the sea. Perhaps these may be indications of the coast having been repeatedly elevated by the same means. Mr. Lyell has introduced other particulars respecting this great disturbance, gathered from the Transactions of the Geological Society, confirmative of the leading phenomenon-the elevation of the coast. The wreck of a ship which could not be approached previously, became accessible from the land, although its distance from the original shore had not altered. The water-course of a mill, a mile from the sea, gained a fall of fully a foot in a hundred yards. The rise upon the coast was from two to four feet, but in some inland situations it amounted to as much as seven feet. CHAPTER XII. INTERIOR LAND CHANGES. ND surely the mountain falling cometh to nought, and the rock is removed out of its place." "The everlasting mountains were scattered; the perpetual hills did bow. I saw the tents of Cushan in affliction, and the curtains of the land of Midian did tremble." "The sea saw it, and fled; Jordan was driven back. The mountains skipped like rams, and the little hills like lambs. What ailed, O thou sea, that thou fleddest? thou Jordan, that thou wast driven back? Ye mountains, that ye skipped like rams; and ye little hills like lambs?" This language of the more ancient scriptures is not that of poetical exaggeration, but derived from an acquaintance with the physical history of the earth, obtained by testimony or observation. The trembling of the most solid masses the tottering of rocks, hills, and mountains, are not imaginative pictures, but representations founded upon the realities of nature; and when the earth is described as reeling to and fro like a drunkard, when the wilderness of Kadesh is declared to shake, and Lebanon and Sirion to leap like the unicorn, we know the source to which the statement is to be referred. The country of the writers, in almost every century since the first Hebrew patriarch pitched his tent upon its soil, has suffered from the eruption of violent eternal forces, acting with greater energy, perhaps, in ancient than in modern times; and from the great physical changes consequent upon these convulsions, they drew those lofty and terrible descriptions of terrestrial disturbance with which their songs, odes, and elegies abound. Before referring to these subterranean causes of superficial derangement and their phenomena, some of the more ordinary forms of interior land changes may be noticed. In mountainous regions, the detachment of fragments of rock and earth from abrupt and precipitous elevations is the gradual yet sure effect of the wear and tear of the atmosphere, accelerated by the occurrence of severe storms, heavy rains, and intense frost. Mam Tor, a hill on the Peak of Derbyshire, has become celebrated on account of the waste of its mass; and hence it is popularly called in the neighbourhood, the "shivering mountain." The summit of the hill rises about eight hundred feet above the level of the valley, and commands an extensive prospect of the high eminences of the district and its beautiful dales, retreats secluded from the bustle of the world, to which the imagination is ready to assign the attributes under which the happy valley of Rasselas is described. According to vulgar rumour, the shivering of the hill has been going on for ages, without occasioning any diminution of its bulk; but, apart from fable, Mam Tor is a mass consisting of alternate layers of shale and gritstone, and the former readily decomposes under the influence of the weather, falling into the valley below, bringing with it detached fragments of the grit. In the winter season, after unusual rains, or in severe frost, the decomposition is the most rapid, the Tor discharging from its side immense pieces of its material, the noise of which in their descent may be heard in the adjacent villages, and is described as singularly impressive in the night. In all Alpine regions, subject to great seasonal vicissitudes, frost is a powerful agent in the destruction of rocks. When the water that has entered their pores and fissures becomes frozen, it acts by its expansion with irresistible force, and detaches enormous masses, which fall from their parent bed thundering to a lower level. In the upper parts of North America, even in latitude 51° in some places, where the winter climate is so severe that brandy congeals and the lakes freeze eight feet thick, the rocks split with a noise resembling the explosion of artillery, and the shattered fragments fly to a considerable distance. - The action of water, in another way, operates to dislodge from their situation the higher parts of mountains, and sometimes to reduce their whole mass to ruins, producing land or mountain slips. This is by a slow process of erosion and undermining, which, having proceeded to a sufficient extent, brings on in a moment the catastrophe of a slide or fall. The occurrence cannot take place in the case of unstratified rocks, which are only subject to the gradual abrading of their entire mass, and the detachment of small fragments; but with reference to the stratified mountains, where layers of different kinds of rock overlay one another, it is easy to conceive of such slides transpiring. Water percolating by rents and fissures through an upper stratum, and reaching another which readily yields to its solvent power, the lower stratum may be so far carried away in the course of ages as to be unable to support the upper, which, in consequence, falls down. But little harm would ensue, if the different strata were of uniform breadth and horizontally disposed, like a number of equal volumes piled upon each other, instead of displaying varying thickness and all manner of inclination. It is this last condition chiefly-the differently inclined plane upon which the upper stratum descends that causes its precipitation upon the country at the base, covering it with its ruins, and occasionally overwhelming its inhabitants. Other circumstances concur to the production of land and mountain slips; but the principal agent is water, operating by a process of undermining, which, however slow and subtle, is grand and terrible in the crisis that ensues. Such events are by no means uncommon; but they generally occur in secluded and uninhabited sites, so as not to attract any wide notice, unless they happen upon a grand scale. On the night of the 29th of January 1840, in the district of Jura, a mountain called the Carnans came down in mass on the surrounding plain, and a portion of the royal road from Dijon to Portalier sunk with this eboulement to a depth of more than fifty mètres. That portion known as the Rampe de Carnans, the ladder or staircase of Carnans, was rendered impassable, and all communication between the places on each side was entirely suspended. A fresh mass of rock and earth, during the following day, was detached, and was distinctly seen from a great distance as it slid down. It was supposed that a fountain, which ceased to play upwards of a quarter of a century before, had then taken a new subterranean direction, and mined out a portion of the mountain. Switzerland has repeatedly exhibited these extensive falls from her giant mountains, which may form a subject of interesting reference. It has sometimes happened that the waters of an elevated lake have insinuated themselves between the strata composing the mass of a mountain, gradually loosening and removing a quantity of material, by which the superior body of rock or earth being deprived of its support has fallen. In this way, the catastrophe of the Rosenburg, otherwise called Mont Ruffi, is conceived to have been occasioned in the year 1806. Nearly in the centre of Switzerland, in the canton of Zug, is the lake of that name, a lovely sheet of water, and a smaller lake, startled the inhabitants of the valley, who little dreamt of the disaster that was impending. In the afternoon of the day the noises were repeated, becoming more frequent, and some pieces of rock were observed to fall down the declivities of the mountain. Larger masses descended towards five o'clock in the evening, and now the apprehensions of the people were thoroughly awakened; but they had little time either to fear or fly, for a few minutes afterwards a large part of the upper mass of the mountain was seen to give way, and to be coming down upon the valley. Its motion was at first slow, but in a few seconds it acquired a frightful velocity, and with a tremendous crash, the disjoined portion with its forests and buildings was precipitated upon the lower levels, darkening the air with clouds of dust, so as to obscure for a time all further perception of the catastrophe. Some of the spectators of this event were in a house at the base of Mont Righi on the opposite side, at an elevation of three hundred feet above the bottom of the valley; but such was the tremendous impetus given to the rocks in their descent, |