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Show 408 EARTHQUAl{E OF SOUTH CAROLINA, 1811. a degree as to create lakes and islands. Flint, the geog~apher, h visited the country seven years after the event, mforms w 0 us, that a tract of many miles in extent, near t he LI' tt1 e P ram..e , became covered with water three or four feet deep.; a?d when the water disappeared, a stratum of sand was left .m Its place. Large lakes of twenty miles in e~tent we!·e formed m the course 0 f n hour and others were drmned. 'I he grave-yard at New Maad rid wa's precipitated into the bed .of the MI' SS. iss.t pp.l. Th e inhabitants related that the earth rose m great undulatiOns; and when these reached a certain fearful height, the soil burst, and vast volumes of water, sand, and pit-coal, were discharged as high as the tops of the trees. Flint s~w hu.ndreds of these deep hasms remaininO' in a tender alluvial sml seven years after. ~I1e people in the country, although ine~perienccd in su~h convulsions had remarked that the chasms m the earth were m a direction from S.W. to N.E.; and they accordingly felled the tallest trees, and, laying them at right ang.les. to tl~e chasms, stationed themselves upon them. By th1s mvenhon, when chasms opened more than once under these trees, several persons were prevented from being swallowed up·*. At one period during this earthquake, the grou~d .no.t f~1~ b~low New Madrid swelled up so as to arrest the Mtsstsstppl_,m 1ts c~ursc, and to cause a temporary reflux of its waves. 'I he mo~10n of some of the shocks was horizontal, and of others perpendiCular; and the vertical movement is said to have been much less deso- 1 tin()' than the horizontal. If this be often the case, those s~ocks which injure cities least may often produce the greatest alteration of level. Aleutian Islands, 1806.-In the year 1806 a new isl~nd, in the form of a peak, with some low conical hills upon It, rose f om the sea amonO' the Aleutian Islands, north of Kat~lt· s~hatka Accordin; to Langsdorf t' it was four ge?grapluc~l miles i~ circumference ; and Von Buch infers from Its hm~gmi tude, and from its not having again subside.d below t e ~~:e of the sea that it did not consist merely of eJected matter, Monte N u' ovo, but of so I1'd roc k up1 le ave d *. Another e1x4t ra. · ordinary eruption happened in the spring of the year 18 'm * Silliman's Journ., Jan., 1829. .. 09 t Bcmerkuugenl auf einer Reise um die Welt.~ bd. u.l s. 2 • ALEUTIAN ISLES, 1806-NEW ISLANDS THROWN UP. 409 ~he sea near U nalaschka, in the same archipelago. A new 1sle was then produced of considerable size, and with a peak three thousand feet high, which remained standinO' for a year afterwards, though with somewhat diminished heiO'ht. Al.though it is not improbable that the earthq~akes accompanymg the tremendous eruptions above mentioned may have heaved up part of the bed of the sea, yet we must wait for fuller information before we assume this as a fact. The circum. stance of these islands not having disappeared like Sabrina, may have arisen from the emission of lava. If Jorullo, for example, in 1759, had risen from a shallow sea to the height of one thousand seven hundred feet, instead of attaining that elevation above the Mexican plateau, the massive current of basaltic lava which poured out from its crater would have · enabled it to withstand, for a long period, the action of a turbulent sea. We are now about to pass on to the events of the eighteenth century; but, before we leave the consideration of those already enumerated, let us pause for a moment, and reflect how many remarkable facts of geological interest are afforded by the earthquakes above described, though they constitute but a small part of the convulsions even of the last thirty years. New rocks have risen from the waters; the coast of Chili for one hundred miles has been permanently elevated; part of the delta of the Indus has sunk down, and some of its shallow channels have become navigable; the town of Tomboro has been submerged, and twelve thousand of the inhabitants of Sumbawa have been destroyed. Yet, with a knowledge of these terrific catastrophes, witnessed during so brief a period by the present generation, will the geologist declare with perfect composure that the earth has at length settled into a state of repose? Will he continue to assert that the changes of relative level of land and sea, so common in former ages of the world, have now ceased? If, in the face of so many striking facts, he persists in maintaining this favorite dogma, it is in vain to hope th~t, by accumulating the proofs of similar convulsions during a senes of antecedent ages, we shall shake his tenacity of purpose, Si frnctus illnbatur orbis Impaviuum ferient ruinoo. 11< Neue Allgem, Geogr. Ephemer. bd. iii.1 s. 348. |