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expert medical testimony at a murder comes eligible to compete with some trial, of an island continent in the ocean urban rapid transit systems. off the entrance to the Mediterranean All this happened a generation ago? which was the cradle of civilization. Its Yes, but just wait a minute. Dr. George people were the conquerors of Europe H. Cook, formerly State Geologist of and Egypt, the colonizers of the Ameri- New Jersey, estimated that the coast of cas, the progenitors of the Mound-build- the state was subsiding at the rate of ers and the Aztecs. This island, which two feet a century, or a quarter of an Plato called Atlantis, with all its inhabi- inch a year. The mean seaward slope tants was swallowed by the sea ata of the coastal plain being six feet to the single gulp in one dread day and night. mile, this would give a third of a mile
Then there are the British Isles which per century as the rate of the sea's enare proved by circumstantial evidence to croachment upon the land. Dr. Cook have been, once upon a time, a .part of being a mere geologist, engineers could the continent of Europe. The waves of not accept his unsupported statement the Atlantic, pounding ceaselessly away, about the rate of subsidence. So the at last gouged a channel through some United States coast survey established low-lying lands between Dover and bench marks and put up self-registering Calais and isolated the islands as a pack tide gauges to test the matter. This was of wolves by patient maneuvering might a work of years, of course. cut out a calf from the herd. And there Now here is where we get up to date. is Australasia, which is but the meager When the Government employes wearied remnants of a once vast continent which of the tide gauges the New York City was swallowed by the insatiable waters. topographical engineers took up the ob
But leaving out of consideration cir servations. Recently the story the tide cumstantial evidence, dug up by those gauges told was compared and verified who have nothing better to do than to go and corrected and tested and analyzed nosing about trying to pry into Nature's for the whole series of years. When the secrets, of transformations in prehistoric final result was before them the city entimes, there still remain changes in mod gineers had to admit that Dr. Cook had ern coastlines great enough to be of only erred .55 of a foot per century so more than passing interest. Some of the far as the subsidence of the coasts of most striking of these changes are along New York Harbor were concerned, our own water front.
which wasn't at all bad for a geologist. Inaccuracy and exaggeration by en- In other words, they found that while gineers—the fellows who drive tunnels the tide gauges varied somewhat at from opposite sides of rivers and moun- different points, the apparent average intains and make the ends meet in the crease at half tide level was 1.45 feet black bowels of the earth something less per century. Mind you, they said apparthan the fraction of a hair's breadth outent. An engineer wouldn't admit that of alignment—would be unthinkable, coal was black until he had brought his wouldn't they? Well, the engineers of theodolite to bear upon it and had worked the United States Coast Survey who out the result with a table of logarithms. mapped the coast of Long Beach for And anyway, they said, this did not mean twelve miles south of Barnegat Inlet in that the sea was really rising; it must 1839 found upon going over the ground be the land sinking if anything was hapin 1871 that the sea in thirty-two years pening. In other words, the patient's had advanced inland an average of 545 leg is fractured, not broken. With this feet for the entire distance, and in some as a basis any one who is good at figures places as much as 930 feet. Also they can compute the exact time when the found that beginning at the mouth of Flatiron Building will be submerged. Dennis Creek in Cape May County the It is not necessary to be an engineer sea had swallowed 2,310 feet of that or even a geologist to be able to perstream and 1,880 feet of East and West ceive that the sea is advancing upon the creeks. When the sea can exhibit an eastern and southern coasts of the United official record of progress at the rate of States. Submerged stumps, some of twenty-three feet a year it almost be- them of trees cut down by man, and
lagoons and marshes submerged all ing waters. Then there are the keys along the coast from New Jersey to which skirt the coast all the way around Florida within the memory of men now Florida and on to Alabama. The keys living and the decreasing power avail- are the high places on lands not yet comable for mills and factories on tidal pletely submerged. They are separated streams all tell the story of the advanc- from the mainland by shallow sounds from a third of a mile to five miles wide which were the low-lying lands which first succumbed to the onslaught of the sea. West of Mobile Bay the keys have gotten out from ten to fifteen miles from the mainland where, being now quite beyond their depth, they are all drowned except a few of the largest which are now dignified by the name of islands.
A tragic incident in this slow drowning of a
SHORE LINE JUST NORTH OF BRIDLINGTON, ENGLAND. continent occurred on
The footpath on the cliff has to be continually set back. the night of August 10, 1856, when a sudden storm burst upon ing the jetties at the mouth of the Misthe Gulf, lashing its waters to such a fury sissippi. On Belize Bayou, a former outthat L'Isle Derniere, one of the prettiest let of the river, was an old Spanish fort of these islands, which had been occupied built two hundred years before. When as a summer resort by the richest and the engineers found it the water was oldest Creole families of New Orleans, ten feet deep over the door-sill of the was overwhelmed with all its inhabitants. magazine. Even if the water had been Next day nothing but a mud bank, which level with the sill when it was laid, which has been covered at high tide ever since, isn't likely, the rate of subsidence must remained to mark the spot where beauti- have been five feet a century. The ful L'Isle Derniere had been.
magazine was level and there were no West of the mouth of the Mississippi cracks in the walls, showing that it was the Gulf has encroached upon the land settling evenly beneath the waters. It from fifty to one hundred miles. Here continued to sink while it was under there are neither keys nor their big observation during the building of the brothers, the islands.
jetties. But the most singular feature of One interesting evidence of the steady the land around the mouth of the Misadvance of the sea upon the southern sissippi is not that it is sinking but that coast was found by the engineers build- it also stretches like wet rawhide. It is
so elastic and untrustworthy that the jetty engineers could not maintain reliable bench marks, level heights and tide gauges for reference purposes. A carefully measured base line 700 feet long was found to have stretched twelve feet in five years.
This subsidence of the coast, according to the geologists, is caused by the great weight of the detritus deposited upon the edge of the ocean
floor by the great rivers. ALONG THE YORKSHIRE COAST, ENGLAND,
The Mississippi and its WATER-WORN BLUFF AT ROCKY POINT, PLYMOUTH, MASSACHUSETTS. tributaries which are so thick with mud of the waters has been much more rapid, that their waters look as if they needed averaging for the last forty years 1,523 casters to enable them to run down hill, acres a year. The ravages of the sea in dump 400,000,000 tons of sediment on 1903 were almost-unprecedented. the edge of the Gulf every year, which Many historical towns, such as Ravensseems quite enough to tip up several burgh, where Henry IV landed in 1339, states. Yet all the rivers of the world, have been submerged. Off the Yorkand that includes the Ganges, which in shire coast alone there are twelve subthe average rainy season of 122 days merged towns and villages. Between carries six thousand million cubic feet of Flamborough Head and Kilnsea 73,780 earthy matter, a bulk equal to forty of acres, an area equal to that of London, the pyramids of Egypt, do not transport has been devoured by the waves since enough sediment to fill up the sea to any the Roman invasion. The erosion here appreciable extent. If an Englishman is so continuous that the outline of the named Taylor made no mistake in his coast is never the same on two consecucalculations all the detritus carried by all tive days. On the Holderness coast, a the rivers of the world in ten thousand stretch of forty miles, 1,904,000 tons of years would only make a layer three material are washed away annually. inches thick if it were spread evenly all Spurn Point is about to be made an over the bottom of the sea.
island. The rivers which empty into the At- There is an anchorage off Selsey, lantic are not so turbid as the Mississippi, Sussex, still called "The Park” because yet they deposit an ever increasing load it was a royal deer park in the reign of of detritus on the ocean floor near their Henry VIII. The Goodwin sands, so mouths. They do not choke up their much dreaded by navigators, was the entrances because the bottom of the sea 4,000-acre estate of Earl Godwin until sinks as rapidly as the mud accumulates. it was inundated by a great wave in
On the other side of the Atlantic the 1099. In June, 1898, the sea advanced coast line is retreating before the cease- inland two hundred yards at Cromer less onslaughts of the waves even more during a single gale. Between Cromer rapidly than here. Forty years ago the and Happisburg, a stretch of sixteen area of Great Britain was 56,964,260 miles, the annual loss is twelve acres. acres; today the figures are 56,748,927 All along the coast the same deacres. The difference, 215,333 acres, structive process is going on continurepresents the amount that has been ously. The Shetland Islands, off the swallowed by the sea. England alone has coast of Scotland, are composed of very surrendered 524 square miles of her ter- hard rocks; yet so violent is the action ritory to the waves within the last thou- of the waves and currents that what were sand years. More recently the advance once islands are mere clusters of rocks.