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the last fifteen years, been thrice removed inland, in consequence of the advance of the sea.
Along the whole eastern eoast of England, changes similar to these are going on. In some places by the silting up of estuaries,
land is forming, but not near as much, as is being removed. The isle of Sheppey, which is a tertiary formation, now about six miles long, by four in breadth, is rapidly decaying on its north side, fifty acres of land having been lost within the last twenty years. To the east of Sheppey stands the Church of Reculver, upon a cliff of clay and sand, about twenty-five feet high. This place was formerly an important military station in the time of the Romans, and even so late as the reign of Henry VIII, was nearly one mile distant from the sea.
We here give a view of the Church of Reculver taken in the year 1781, copied from the Gentleman's Magazine. At this time the spot had become interesting from the encroachment of the water. It represents considerable space as intervening between the churchyard and the cliff. In the year 1782, the cottage at the right was demolished; nearer the church is shown an ancient chapel now destroyed, and at the extreme right is the Isle of Sheppey. In the year 1806, a part of the Churchyard with some
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of the adjoining houses was washed away, and the ancient church with its two lofty spires, a well known land-mark, was abandoned. The following view of it as it appeared in 1834, is taken from Mr. Lyell’s Principles of Geology, from which the preceding statement is also derived. This ancient building would.
probably, have fallen long since been checked by an artificial causeway of stones, and large wooden piles, driven into the sands to break the force of the waves. There are good reasons for believing that the coasts of France and England were formerly united, this is inferred from the identity of the composition of the cliffs on the opposite sides of the channel, and also of the noxious animals in England and France, which could hardly have been introduced by man. This opinion is advocated by many distinguished geologists, and it is by no means incredible, that in the course of ages the sea may have forced its passage through. The separation of Friesland, which was once a part of North Holland, from the mainland, by the action of the sea in the thirteenth century, and the formation of a strait of about half the width of the English channel in 100 years, lends countenance to this opinion. The inroads of the sea have no where been more severe than in Holland, and even at the present day 12,000 windlinills are employed to drain the Netherlands and to prevent at least two-thirds of the kingdom from returning to the state of bog and morass, and during the past year three immense steam engines, capable of discharging 2,800,000 tons of water in 24 hours, have been employed in pumping out aud emptying through the great ship canal, and sea-sluices at Katwyk, the lake of Haarlem, which by its continual inroads threatened to inundate Amsterdam on the one side, and Leyden on the other. In the year 1836, twenty-nine thousand acres of land were comapletely overflowed by it. The large lake called the Bies Bach was formed in 1621, by the sea bursting through the embankments of the river Meuse, overflowing seventy-two villages. Of these villages no vestiges of thirty-five of them were ever discovered. Since their destruction an alluvial deposit has been formed partly over their site. The island of Northstrand, which in the year 1634, contained 9000 inhabitants, and was celebrated for its high state of cultivation, was, on the evening of the 11th of October, in that year, swept away by a flood which destroyed 1300 houses, 50,000 head of cattle, and 6000 men, leaving three small islets, one of them still called Northstrand, which are continually being wasted away by the sea. Such are some of the powerful effects of currents and waves in altering, and finally sweeping away the headlands and islands which at any particular epoch may have distinguished the line of coast exposed to their force; the eastern side of America, along the Atlantic coast is subject to the same changes. Before leaving this part of our subject, we will describe that peculiar tidal wave called “the Bore.” This is produced, when the channel of a river, into which the tidal wave from the ocean is entering, is so narrow that the water is made to rise suddenly, and thus terminates abruptly on the side away from the sea, or infand; precisely like the waves which break upon a shelving shore. As might be expected, this phenomenon occurs most powerfully at the time of spring, or high
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est tides. The Bore which enters the river Severn is sometimes nine feet high, and at spring tides rushes up the estuary with extraordinary rapidity. In the Hoogly or Calcutta river, says Rennell, “the Bore commences at Hoogly point, the place where the river first contracts itself, and is perceptible above Hoogly town; and so quick is its motion, that it hardly employs four hours in traveling from one to the other, though the distance is nearly seventy miles. The tides of the Bay of Fundy pour twice a day vast bodies of water through a narrow strait, causing in every small stream, an immense tidal wave, rising sometimes to the height of seventy feet. We have already alluded to it: rich alluvial deposits of red marl which have been excluded artificially from the sea by embankments, Heretofore we have noticed only the degrading effects of currents, and tides. It might at first appear that the sediment borne down by rivers, the formation of deltas, and the silting up of estuaries, would compensate for the loss by the encroachments of the sea, this however, is not the case; while in all instances the new-made land is constantly attracting attention, there are no boundaries, or great ratural land marks, to show where was formerly the line of coast. The former demand attention by their presence, the latter are unseen, and therefore lightly estimated; many places where once flourishing cities stood, are now, not only depopulated, but covered with water to a depth of thirty feet. There is therefore good reason for believing that the loss of land by the effects of currents and tides, much more than counterbalances all deposited in the form of dry land. The general tendency of these encroachments is undoubtedly to fill up the bed of the sea, and to finally reduce the surface of the earth to a uniform level; and this would ultimetely be accomplished, but for the counterbalancing force of volcanic or igneous causes, which are continually elevating the surface. If we had space we might continue to enumerate examples of the effects of the ocean in destroying the coasts, not only of our own country, but over the whole world: sufficient however has been said to give some idea of the importance of these causes of change, and when hereafter, we allude to immense formations of rock strata, imbedding numerous fossils, as the sedimentary deposit of an ancient ocean, the statement will not appear incredible. The force of the current of the Amazon extends out into the ocean to a distance of three hundred miles from its mouth, and when we remember how long the mud and fine sand remains suspended even in quiet water, we shall not be surprised to learn that particles brought down from the interior of South America, are perhaps deposited in the Mexican Gulf; for where the great equatorial current from the coast of Guinea crosses the waters of the Amazon, it runs with a velocity of four miles an hour. Vast quantities of driftwood and rubbish are thus carried as far as the mouths of the Orinoco, and are increasing the island of Trinidad. It is the opinion of many distinguished philosophers that the Isthmus of Suez, which now separates the Mediterranean and the Red Sea, is a recent formation, it is at least quite certain that the isthulus is receiving continual accessions on the Mediterranean side. The change of coast, the loss of cities, the formation of bays, the filling up of estuaries and washing away of islands, important as these changes may be, are nevertheless, of less moment than the processes going on in the depths of the sea; far below, where the waters are never disturbed by the storms and winds, which lash the surface into fury, a quiet deposit is going on, in this are now being imbedded the various forms of animal existence which are borne down to the bottom of the ocean. Nor are these all, the wealth of man has gone down, and lies burried deep with his bones in the undisturbed strata. At some distant epoch, when the present ocean bed shall be upheaved, perhaps some patient investigator will exhume the fossils, and moralize upon the eventful change which passeth over all things. We cannot close this chapter better than with the beautiful language of Mrs. Hemans:
“The depths have more : What wealth untold
Yet more — the depths have more | Their waves have roll’d
Sand hath filled up the palaces of old,