Sandbank

“ THE GOODWIN SANDS.
bout six miles off the east coast of Kent there is a sandbank known as the Goodwin Sands, extending for a distance of ten miles, between the North Foreland and the South Foreland. No part of our coast is so much dreaded by the mariner, and from early times it has been the scene of many terrible disasters. As Shakespeare says, it is "a very dangerous flat, and fatal, where the carcasses of many a tall ship lie buried." ”

“ THE BUFFALO AND THE CROCODILE When the rains have all run off, and the snows of Central Asia have not begun to melt, about the middle of the dry weather, the Irrawaddy, our Burman Mississippi, runs its lowest; and in such places as Magwe, a district on the road to Mandalay, the sandbanks are conspicuous. In 1894 there was, as there often is, a sandbank in Magwe district that, starting from the eastern bank, like a dam, athwart the current, bent down the stream, like a breakwater at sea, enclosing a natural harbour between it and the bank. ”

“ In a North 70 degrees East direction from it, at the distance of two miles and three-quarters, is a sandbank with three fathoms; it was discovered by the ships Claudine and Mary, on their passage through Torres Strait, when it was named LARPENT'S BANK.*
(*Footnote. It is near the west end of a shoal of five miles in length, extending in an east and west direction, a few feet only below the surface of the water. Roe manuscript.) APPENDIX A. SECTION 3. ”

“ In its upper reaches navigation is made difficult by banks of mud and sand which are continually altering in shape and position. On the north coast of Devonshire, however, there are no outlying sandbanks. There is a small patch of sand off Lynmouth, 1 1⁄2 miles N.N.W. of Countisbury Foreland, and the estuary of the Taw and Torridge is obstructed by a dangerous and shifting sandbank known as Barnstaple Bar, upon which ("the harbour bar" of Kingsley's song) , many vessels have been wrecked. ”

“ As to the depth of the great sandbank, borings have been made down to the chalk to a depth of seventy-eight feet—a fact which might have been fairly conjectured from the depth of water inside the Goodwins, down to the chalky bottom being nine or ten fathoms, while the depth close outside the Goodwins, where the outer edge of the sands is sheer and steep, is fifteen fathoms, deepening a mile and a half further off the Goodwins to twenty-eight fathoms. ”

“ It is a sandbank where the smugglers and pirates meet for trade with the fishermen, when the Lords of the Night are not too vigilant. A bad place, and one where a law-keeping man may come by much harm. ”

“ Where outlying sandbanks stretch in front of a coast, as for instance the Stroombank in front of Ostend and the adjacent shore, and the sandbanks opposite Yarmouth sheltering Yarmouth Roads, large waves cannot approach the land, for they break on the sandbanks outside. Waves, indeed, always break when, on running up a shoaling beach, they reach a depth approximately equal to their height; and the largest waves which can reach a shore protected by intervening sandbanks, are those which are low enough to pass over the banks without breaking. ”

“ What the amount of sand annually carried down from the north-western portion of Australia into the ocean may be we have no means whatever of ascertaining; that it is sufficient to form beds of sand of very great magnitude is attested by the existence of numerous and extensive sandbanks all along the coast. One single heavy tropical shower of only a few hours' duration washed down, over a plot of ground which was planted with barley, a bed of sand nearly five inches deep, which the succeeding showers again swept off, carrying it further upon its way towards the sea. ”

“ The crew must know well the whereabouts of the continually shifting sandbanks, in order to avoid them, and these, covered as they are with brown water, are very hard to detect at any considerable distance. If the raft strikes one, there is no way of getting it afloat again but by releasing from it one by one the logs which have got fixed in the sand, and putting them back again afterwards. ”

“ But accurate observations regarding the formation of extensive sandbanks, and the accumulation of the débris, of which they are formed, are not to be made in a few years, perhaps not in a century, nor indeed in several centuries; for although the short period of the life of man is sufficient to afford the most incontrovertible217 proofs of the waste of the land where we become observers, yet when we extend our views to the depths of the ocean, and speak of the events and changes which are there going forward, we must not be supposed to set limits to time. ”

“ "Going up that river was like traveling back to the earliest beginnings of the world, when vegetation rioted on the earth and the big trees were kings. An empty stream, a great silence, an impenetrable forest. The air was warm, thick, heavy, sluggish. There was no joy in the brilliance of sunshine. The long stretches of the waterway ran on, deserted, into the gloom of overshadowed distances. On silvery sandbanks hippos and alligators sunned themselves side by side. The broadening waters flowed through a mob of wooded islands; ”

“ Upon examining this sand with a magnifying-glass, its appearance was like so many small shining crystals shooting into numerous points.—It is often a difficult question with mineralogists, to account for the production of sand in many situations upon the coast; but here the question involves no perplexity, as St Andrew’s Bay, which is generally understood to extend from Fifeness to the Redhead, a distance of about 25 miles, is not only bounded by sandstone, but forms the embouchure of the river Tay, and of several other considerable streams, which fall into the sea upon its shores. ”

“ Thus the bank preserves its height as fast as it is worn away. This sand is steadily travelling westward at a rapid rate, "more than a hundred yards," says one writer, within the memory of inhabitants now living; so that in some places peat-meadows are buried deep under the sand, and the peat is cut through it; and in one place a large peat-meadow has made its appearance on the shore in the bank covered many feet deep, and peat has been cut there. This accounts for that great pebble of peat which we saw in the surf. ”

“ It is true that the unyielding stone is not particularly good going, but one is fully recompensed by the intimate proximity of the water. Then one is also able now and then to walk in the sand beside the quay. Yes, there is real sand there between the gravel and the beach-grass, sand that is a trifle mixed with clay and not so sacredly pure as that of the sea, but nevertheless real sand that has been washed up. ”

“ Longshore drift spreads it to the East and West, where it joins sediment contributed by lesser river systems such as the Imo and the Osse (Ovia) .
The sand spreads as a band of islands along the coast. They are mostly 'true islands', completely surrounded by water, be it the Atlantic itself or the water of lagoons and of the creeks that twine their way around islands formed further inshore. Where they form in the mouth of an estuary, they may be called sand bars.
Sand thus thrown up by the Atlantic often forms a high beach, behind which streams running from inland may form a lagoon. ”

“ Such ripple-marked sandstone is far from uncommon. It gives a perfect reproduction of the little sand-ripples or rounded ridges and hollows, often to be found on a sandy shore, either visible through a thin layer of water or left bare after the tide goes down. And it shows us how the sandstone rock must originally have [p. 126] been put together, under water. Soft undulations were made in the wet sand by one high tide, becoming in a measure hardened before the next high tide, and so keeping their shapes, while a fresh supply of sand was dropped upon them, partaking of the same outlines. ”

“ The length of the bank is about one hundred and fifty fathoms, by fifty in breadth, and the general elevation three or four feet above the common level of high water; it consists of sand and pieces of coral, thrown up by the waves and eddy tides on a patch of reef five or six miles in circuit; and being nearly in the middle of the patch, the sea does no more, even in a gale, than send a light spray over the bank, sufficient, however, to prevent the growth of any other than a few diminutive salt plants. ”

“ Sand makes a poor road. To get a reasonable result it was necessary to collect the big stones of the seashore and carry them to the shore edge of the beach and place them as a foundation; on the top of this, clay was deposited—carted from the hillside near by in the mule carts of the Indian transport service; the whole was top-dressed by the sand of the beach, and finally, the hard-worked soldiers carried petrol tins of water from the sea and poured it over the surface to make the material set. ”

“ Upwards, the conglomerate becomes finer and shades off into sandstone, and finally into shale, showing that the water has become gradually deeper and more tranquil, the shore having, in consequence of the subsidence, advanced toward the land. The next two strata show that this movement is probably reversed; at any rate, the currents become stronger again, and the shale passes gradually into sandstone and conglomerate. The beach condition prevails now for a long time, and thick beds of sand and gravel are formed. ”

“ As the river-bed rises, the banks also rise. This is brought about by the more luxuriant vegetation and the activity of the husbandmen in the neighbourhood of the banks, as well as by an occasional overflow, when naturally the largest share of sediment is deposited near the river. Thus the river flows over what may be termed an artificially raised bed between two raised banks; the surface of the water is actually higher than the plain beyond the banks, a difference which the unaided eye can scarcely detect as it deals with a rise of only a few metres over an extent of several hundred. ”

“ They consist of a more soft, fluid, porous, spongy, but withal tenacious substance, than the neighbouring sands, and are consequently of such a quality, that when a ship strikes upon them there is but very little chance of her getting off: the nature of the sand being to swallow its prey in a few hours, while the surf, which breaks over them, frustrates all attempts to approach the ill-fated vessel. When the tide, however, has ebbed sufficiently, these sands become so hard and firm that cricket-matches have been played upon them. ”

“ If these submerged outer banks were to be swept away by some change in the set of the currents, large areas now cultivated and inhabited would be flooded by salt water at every spring tide, and the turf of the meadows would be covered by a layer of marine silt, such as we see alternating with the submerged forests in the docks of the Thames. Such alternations, if thin, do not necessarily prove a change in the level of the sea; they may only point to the alternate accumulation and removal of sand-banks in a distant part of the estuary. ”

“ I have said that the flat promontory occupied by the ruin is edged by hills of indurated sand. Existing in some places as a continuous bed of a soft gritty sandstone, scooped wave-like a-top, and varying from five to eight feet in thickness, they form a curious example of a sub-aërial formation,—the sand of which they are composed having been all blown from the sea-beach, and consolidated by the action of moisture on a calcareous mixture of comminuted shells, which forms from twenty to twenty-five per cent. ”

“ Large sand-banks have been completely removed by the impetuous whirls of the waters, and have been deposited in other places. Some appear quite new to the eye of the navigator, who has to mark their situation and bearings in his log-book. The trees on the margins of the banks have in many parts given way. They are seen bending over the stream, like the grounded arms of an overwhelmed army of giants. Everywhere are heard the lamentations of the farmer and planter, whilst their servants and themselves are busily employed in repairing the damages occasioned by the floods. ”

“ The dry part of this sand-bank is so very small, that in bad weather the sea must break entirely over it: there is regular soundings between it and the Brothers, from twenty-five to seventeen fathoms. Being now determined not to stand farther to the westward than we could by that means gain southing, we, by the different changes of the wind, got, by the 19th, as far as 4° 42' south latitude: that morning, as we were steering to the westward, ground was discovered under the ship which of course drew every body on deck; we had ten fathoms, over a rocky bottom, which we saw very distinctly. ”

“ The existence of a shoal, or the shifting of a sand-bank, may mar or diminish the prosperity of a city; and to the great local changes which this part of the Kentish coast has undergone, the decay of Sandwich, as a harbour, is chiefly to be ascribed. Where fleets of merchantmen once rode in safety; where the busy scenes of lading and unlading once offered pictures of maritime prosperity, the fishing-craft of the place can hardly find anchorage, and all the characteristics of a flourishing port have disappeared ”

“ Being fully exposed to the sea-breezes in three directions it is healthy, and the soft sandy heath offers great facilities for hauling up the praus, in order to secure them from sea-worms and prepare them for the homeward voyage. At its southern extremity the sand-bank merges in the beach of the island, and is backed by a luxuriant growth of lofty forest. ”

“ All round the largest is a sand-bank above water, which extends from the foot of the higher land about half a mile into the sea, and may have shoal water from it. We saw on the beach a few natives running along shore, as the ship sailed past. These islands are dangerous to people in the night, on account of the sandy spits which project from them; they were covered with shrubs, and had but few tall trees on them, and the land is but low: the latitude of the large or eastmost island, is 8° 06' north, and longitude 140° 03' east. ”