Years. 1726. A violent storm changes the salt marsh of Araya, in the province of Cumana, into a gulf several leagues wide. 1770-1785. Currents and tempests hollow out a channel between the high and the low parts of Heligoland, and transform into two islets this island, so extensive before the eighth century. 1784. A violent storm, according to M. Hoff, forms the lake of Aboukir, in Lower Egypt. 1791-1793. New irruptions destroy the dykes, and carry off other parts of the already reduced island of Nordstrand. 1803. The sea sweeps away the last remains of the priory of Crail, in Fifeshire. The most remarkable alteration of the coast line mentioned in this record, as the effect of a sudden invasion of the ocean, is that which originated the present Zuider Zee, or the South Sea, so called to distinguish it from the North Sea, or German Ocean, a great gulf dividing Friesland, Drenthe, and Gelderland from Holland and Utrecht. This gulf covers an area of about 12,000 square miles, and is about twice the size of the county of York. It was not in existence in the time of the Romans, but a low swampy marsh occupied its place, drained by the river Yssel. In this district there were several lakes, particularly the great lake Flevus, mentioned by Tacitus and Pomponius Mela. The former relates the arrival at it of the Roman fleet under Germanicus, through the canal of Drusus, an artificial branch connecting the Rhine and the Yssel. No material change appears to have occurred here before the commencement of the thirteenth century. Then the sea broke over the isthmus which connected Friesland with North Holland, ultimately cut it away, forming the present Straits of Staveren. The lake Flevus was absorbed, a considerable portion of the surrounding country was submerged, and the Zuider Zee was constructed by the advance of the ocean in the form and depth which it still preserves. If, as the Persic verses affectingly state, describing the transitory nature of human greatness, "The spider has wove his web in the imperial palace, And the owl hath sung her watch-song on the towers of Afrasiab, it is no less true that the features of nature have alternated as strikingly, marine inhabitants sporting in sites where land animals have roamed in sylvan scenes; and we may fairly accept these changes, which are known to have transpired since the date of authentic history, as samples of the revolutions that occurred at a more remote period, of which no chronicle has been preserved. It has been supposed, that as the Straits of Staveren were closed prior to the thirteenth century, the sea then cutting its way through the isthmus, so were the Straits of Dover once occupied by an isthmus, connecting the coasts of England and France, which a violent irruption of the ocean partially destroyed, and then gradually scooped out the present channel. There is nothing contrary to the analogy of undoubted physical events in this supposition, and it is supported by some striking evidence. Desmarest argued in its favour from the identity of the cliffs in composition on each side of the channel, from the fact of a submarine chain running from Boulogne to Folkestone only fourteen feet under low water, and from the circumstance that the same noxious animals are common to both countries, which could never have themselves effected the passage of the straits, and which man would not have introduced. The bolder coasts seem to present an impregnable front to the attack of storms and tempests, both by their height and the rocky materials of which they are composed; yet, however they resist the farther progress of the waves, when the sea, swollen by tides, and agitated by the blast, rises and beats against them with inconceivable fury, the continual action of the water slowly consumes their masses. The perpetual play of waves, tides, and currents gradually wastes away the base of towering cliffs; and when this process of undermining has reached a certain extent, the upper parts, deprived of support, fall down, and, after their destruction, a fresh attack commences upon the coast line. This demolition proceeds at a varying rate, according to the hardness or yielding nature of the material that forms the shore. The granite rocks endure for centuries the wear and tear of the ocean with but little loss, while the limestone and chalk cliffs are more easily subdued. The chalk cliff at Dover has suffered large and repeated losses since Shakespeare wrote the notice of it in King Lear: "The crows and choughs that wing the midway air The fishermen that walk upon the beach Almost too small for sight. The murmuring surge, That on th' unnumber'd idle pebbles chafes, Lest my brain turn, and the deficient sight Immense fragments have frequently fallen from this cliff, owing to the undermining of its base, some of which have shaken the neighbouring town as by an earthquake, and the considerably abridged by these detachments, the slope of the The slipping down of large masses of steep coast is a phecause-the loosening of the foundations by the incessant height of the cliff has been hill being towards the land. nomenon due to the same assaults of the ocean upon it, in connection with the action of springs, which filter through, displace the softer strata, and leave the more solid formations destitute of support. The Undercliff in the Isle of Wight, a series of terraces, some of which have been long settled, while others are more recent and ruinous, is an example of these landslips. They occur upon a grand scale along the coast of the Crimea, where extensive tracts of the shore are often dislodged, sinking down as they slide forwards, sometimes bearing with them the trees, and the houses of the natives, uninjured. A slip of this kind took place at Folkstone, on the coast of Kent, about the year 1716, when a solid mass of chalk resting on clay moved gradually towards the sea, "just as a ship is launched on tallowed planks;" and part of the promontory of Beachy Head, three hundred feet in length, in a similar manner gave way in the year 1813. Hutchins records a memorable slide in his History of Dorsetshire, which happened on that shore in 1792 :-" Early in the morning the road was observed to crack. This continued increasing, and before two o'clock the ground had sunk several feet, and was in one continual motion, but attended with no other noise than what was occasioned by the separation of the roots and brambles, and now and then a falling rock. At night it seemed to stop a little, but soon moved again, and before morning the ground, from the top of the cliff to the water-side, had sunk in some places fifty feet perpendicular. The extent of ground that moved was about a mile and a quarter from north to south, and six hundred yards from east to west." - 66 Electricity the action of ordinary atmospheric changes the incessant percolation of springs the violent, and more gentle yet constant dash of the waves - these are causes which operate to dislodge the masses from a rocky coast which are found lying in chaotic confusion upon many a beach, doomed finally to decay from the still continued influence of some of the agencies that have effected their disruption. but undergoing great annual changes in their disposition when situated upon an exposed shore. In the Shetland Isles, upon which the Atlantic bears with unchecked power, enormous blocks are every winter shifted by the might of its waves, and sometimes transported to a considerable distance, even up the slope of an acclivity. "The Isle of Stenness," says Dr. Hibbert, "presents a scene of unequalled desolation. In stormy winters, huge blocks are overturned, or are removed from their native beds, and hurried up a steep acclivity to a distance almost incredible. In the winter of 1802, a tabular-shaped mass, eight feet two inches by seven feet, and five feet one inch thick, was dislodged from its bed, and removed to a distance of from eighty to ninety feet. I measured the recent bed from which a block had been carried away the preceding winter (1818), and found it to be seventeen feet and a half by seven feet, and the depth two feet eight inches. The removed mass had been borne to a distance of thirty feet, when it was shivered into thirteen or more lesser fragments, some of which were carried still farther from thirty to one hundred and twenty feet. A block, nine feet two inches by six feet and a half, and four feet thick, was hurried up the acclivity to a distance of one hundred and fifty feet." Speaking of the island of Roeness, he states: "A mass of rock, the average dimensions of which may perhaps be rated at twelve or thirteen feet square, and four and a half or five in thickness, was first moved from its bed, about fifty years ago, to a distance of thirty feet, and has since been twice turned over. But the most sublime scene is where a mural pile of porphyry, escaping the process of disintegration that is devastating the coast, appears to have been left as a sort of rampart against the inroads of the ocean; the Atlantic, when provoked by wintry gales, batters against it with all the force of real artillery, the waves having, in their repeated assaults, forced themselves an entrance. This breach, named the Grind of the Navir, is widened every winter by the overwhelming surge that, finding a passage through it, separates large stones from its sides, and forces them to a distance of no less than one hundred and eighty feet. In two or three spots, the fragments which have been detached are brought together in immense heaps, that appear as an accumulation of cubical masses-the product of some quarry." We have other examples of the resistless power of the element, in the hollowing out of caverns in the rocks exposed to a boisterous sea, and in the fretted and columnar appearance of promontories. Some fine instances occur in the Flamborough chalk cliffs, the Filey Bridge rocks, and those of schistus near Whitby, in the latter of which the cave called Hob-Hole had some years ago a most romantic appearance, having a double pillar in the middle of the entrance. But these aspects are destined to undergo further change, by the continuous agency of the cause which has produced them. The pillar in Hob-Hole has been demolished by the waves, insulated masses in its vicinity, plainly bespeak their original connection with the cliffs on shore, though now six hundred feet from them, the perforation of the former having been effected by the same devastating power to which the detachment of the rock itself from the parent island is to be attributed. In the same district, there can be no doubt that the five rocks called the Needles once formed the western extremity of the island, and have been insulated from it and from each other, and reduced to their present shape and size, by the fury of the waves. Though now of considerable extent and altitude, their ultimate fate is not questionable, the original Needle or spiral rock which gave the name to the group, and which was 160 feet high, having vanished below the surface of the water in 1764, in consequence of the undermining of its base. Since the year 1770, a current has cut a passage through the remaining portion of Heligoland, once a celebrated stronghold of the Saxons, but largely reduced by the sea during the middle ages, and ships now sail between the two islands into which it has been formed. The formation of Start Island out of the north-east promontory of Sanda, one of the Orkneys, divided by the sea, is an operation of modern times; and appearances indicate that the Isle of St. Mary-one of the Scilly group-will, in no long course of time, be cut in two. The authentic details which have been collected respecting the gradual waste of several parts of our own coast, are of singular interest, and exhibit a large amount of land swept away by the encroachments of the ocean. The Castle of St. Andrews, on the coast of Fife, had in Cardinal Beaton's time a tract of land intervening between it and the sea; but this has entirely disappeared, with some of the ruins of the castle, the rest of its remains, standing on the edge of a cliff, serving as a landmark for seamen. Mr. Stevenson, an engineer, states, that from St. Andrew's northward to Eden Water and the river Tay, the coast presents a sandy beach, and is so liable to shift, that it is difficult to trace the change it may have undergone. It is certain, however, that within a recent period the sea has made such an impression upon the sands of Barrey, on the northern side of the Tay, that the light-houses at the entrance of the river, which were formerly erected at the southern extremity of Buttonness, have been from time to time removed about a mile and a quarter farther northward, on account of the wasting and shifting of these sandy shores, and that the spot on which the outer light-house stood in the seventeenth century is now two or three fathoms under water, and is at least three quarters of a mile within flood-mark. At the ancient town of Burghhead, to the north of the Spey, an old fort or establishment of the Danes was built upon a sandstone cliff, which, according to tradition, had a very considerable tract of land beyond it, but it is now washed by the waves, and overhangs the sea. The old town of Findhorn has been destroyed by the ocean, and the site of it is now overflowed by every tide. At Fort George, some of the projecting bastions, formerly at a distance from the sea, are now in danger of being undermined by the water. Similar destroying effects have been gradually produced by oceanic action along the east coast of England. The Abbey of Whitby, at its first erection by Lady Hilda in 658, is reported to have been a mile from the sea; but the distance from the verge of Whitby east cliff to the nearest part of the abbey, measured in the line of the transept, was found in 1816 to be little more than 200 yards. Along the coast line of Yorkshire, from Bridlington Quay to Spurn Point, the shore has no important inlet or projection, and consists of beds of clay, gravel, sand, and chalk rubble; and exposed to a strong current from the north, as well as to the uncontrolled action of the waves, the annual devastation committed here is very extensive. Of the villages of Auburn, Hartburn, and Hyde, in the Bay of Bridlington, only the remembrance remains. Several places on the shore preserve, in the termination of their names, a memorial of meres, or fresh-water lakes, once having existed in their neighbourhood; as Skipsea, Kilnsea, and Withernsea, the Scandinavian sjo signifying a lake; but the sea has broken into these meres, and absorbed them, though recesses on the shore seem to mark the spots they once occupied. The mere at Hornsea still survives; but this place, which was once several miles inland, has been brought within half a mile of the water edge, and the hamlet of Hornsea Beck been utterly destroyed. The waste of the coast |