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Show 242 DELTA OF TilE GANGES. 0 . rkable excep t1o o n ' however' occu· rs hto distance. ne rema f th bottom. for opposite t e the regularity of the shab: ~ista:cc of thirty or forty miles middle of the delta, atl t . 1 space called the '' swatch of t . a near y ctrcu ar d' from the coas ' Is .1 I'n diameter, where soun mgs d ,, b ut fifteen mi es .c '1 no groun , a 0 d d nd even one 1m nd red and thirty fathoms, 1a1. of one hun1 rbe t' t a T hI' S p l1 eno menon is the more extra.o rdt-to reach t 1e 0 . h do m. sion occurs WI' th1'n five miles of the lme o. f nary, smce t e epres d th waters charged with Gangetic shoals; and not o~ly 0 . ell but during the monsoons, . ver 1t contmua y, ' · 1 sediment pass 0 ] d d .t h mu d an d sa nd ' is beaten back m t 1at the sea, oa e WI d 1 A the mud is known to extend direction towards the .e ta.th ~ulf we may be assured that, for eighty miles farth~· mto :l~tio~ of strata in,, the swatch" in the course of ages, t e a~:u; ss . and we seem entitled to has been of enormous t d~c t~e at' the spot, that the original deduce, from the present ¥ th Bay of Bengal were on as inequalities of the ~ot~~:s~ of :he main ocean. Opposite the grand a scale as at~ . . and immediately south of Sager mouth of the Hoog y nvler, st land of the delta, a new .c ·1 from t 1e neare Island, 1our mt es 1 . . t ears ago, called Edmonston isle was formed a~out .t ~;h~u~e and the surface of which is Island, where there Is a h~ d 'shrtibs But while there is d · th vegetatiOn an · now'd coveref .W I 'd ga.m at some pom. t s, the general progress of evi ence ~ tapt £ . h tides which rise from thirteen to the coast IS very slo~, fr t e loyed in removing the alluvial sixteen feet, are actlv~ Y emp 'd * The new strata d d'fF · t over a wi e area. matter, an 1 usmg 1 d. ch at least are the only consist entirely of sand anddfine ~u .' sr~g;lar beds,on the banks materials which are exkpsos~ot~u~:~~~e so coarse as gravel occurs of the numerous cree . f, h dred in any part of the delta, nor nearer the sea than our u ~~ficial '1 It should be observed, however, t~at the s p b'd mal1l uevs.i al beds, which are thrown d own rapt dly from tur 1 . 1825 by Captain Hosburgh, "' It is stated in the chart published m the year fi ' and five miles farther that tho sands opposite the whole delta. str~tched bet~~~~s ::taken as the measur~ south than they had done forty years preVIously; an 1 • d But that gentleman lta ·t lf d ilg the same peno · t of the progress of the de 1 se ' ur ~. the ancient charts, during a recen informs me that a. more careful comparison ~f t . their latitudes, so that the urvey has proved that they were extremely mcorrec m d : ~dva.n~e of the new sands and delta was greatly exaggerate . - DELTA OF THE GANGES-CROCODILES. 243 waters during the floods, may be very distinct from those deposited at a greater distance from the shore, where crystalJine precipitates, perhaps, are forming, on the evaporation of so great a surface, exposed to the rays of a tropical sun. The separation of sand and other matter, held in mechanical suspension, may take place where the waters are in motion; but mineral ingredients, held in chemical solution, would naturally be carried to a greater distance, where they aid in the formation of corals and shells, and, in part, perhaps, become the cementing principle of rocky masses. Among the remarkable proofs of the immense transportation of earthy matter by the Ganges and Megna, may be mentioned the great magnitude of the islands formed in their channels during a period far short of that of a man's life. Some of these, many miles in extent, have originated in large sand-banks thrown up round the points at the angular turning of the river, and afterwards insulated by breaches of the stream. Others, formed in the main channel, are caused by some obstruction at the bottom. A large tree, or a sunken boat, is sometimes sufficient to check the current, and cause a deposit of sand, which accumulates till it usurps a considerable portion of the channel. 'rhe river then borrows on each side to supply the deficiency in its bed, nnd the island is afterwards raised by fr·esh deposits during every flood. In the great gulf below Luckipour, formed by the united waters of the Ganges and Burrampooter (or Megna), some of the islands, says Rennell, rival in size and fertility the Isle of Wight. While the river is forming new islands in one part, it is sweeping away old ones in others. Those newly formed are soon overrun with reeds, long grass, the Tamarix Indica, and other shrubs, form .. ing impenetrable thickets, where tigers, buffaloes, deer, and other wild animals, take shelter. It is easy, therefore, to per .. ceive, that both animal and vegetable remains must continually be precipitated into the flood, and sometimes become imbedded in the sediment which subsides in the delta. Two species of crocodiles, of distinct genera, abound in the Ganges and its tributary and contiguous waters; and Mr. H. T. ~olebrooke informs me, that he has seen both kinds in places far I~land, many hundred miles from the sea. The Gangetic croco .. dtle, or Gavial (in correct orthography, Garial), is confined to R2 |