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Show 192 FLOODS, BtTRSTING OF LARES, ETC. d th . O'ncous as we 11 as t11e aqueous causes1 o' f· change. out regar to e 1 o b . that the inequa 1tles pro- It is scarcely necessary to ~ slet vc, d r· the study of the allu-b h ck mJO'Jt ren e duced even y one ~ ~ : . 0 t me future period, most per-vial plain of the MlSSlSSlpplt, a ldso. ason on the distribution of . 1 0'. st who s wu re fi . plexmg to a geo o?l without being aware that the c?n gura-transported materials, . d t . 1 ·ally during the tnne when . l d varle rna ei tion of the country Ja . . of the river was greatest. . emovmO' power . l the excavatmg or r . Sl~ of which New Madnd wast 1e The region convulsed m 1 h ' h le basin of the rrhames, and d d · 1 ngth t e w o . centre, excee e m e d . l ctl' ve volcanos more d1stant necte Wlt 1 a l the shocks were .con narc the extinct craters of the.Eyfe or from New Madnd tha If therefore during the mnumerof Auvergne from. London. ] b l·e forth in succession in the able eruptions wluch forme~~ ;o "the basin of the principal Parts of Europe last alhfl e ot,l agitated and the relative . . . 1 d was reg uen y ' . . ~ n ver of om 1s an l . d (an hypothes1s m per1ect f . 1 parts a ter e ' levels o Its severa l ) tl1e difficulties of some · 1 dern ana ocry ' accordance wit 1 mo b .o ed . and they might no . h haps e r emov , . theorists m1g t, per ' d the necessity of resortmg to longer feel themselves ud~ er ourse of Nature, when they l t of the or mary c · · catastrop 1es ou . 11 . 1 benomena of that d1stnct. endeavour to explam the a uvia P FLOODS, BURSTING OF LAKES, &c. . 'nO' water may exert, in the lapse of 'The power which runm o. 11 does not so much de- 'd . d deepenmO' a va ey' . acres, in WI emng an - l ·t f the stream usually flowmg P~nd on the volume and ve ocdl y o 't de of the obstructions in it, as on t h e numb er an. d magmo sue d its free passage. If d . .tr t peno s opp · which have, at Jueren ~ t lly dammed up, the SlZC 11 be euec ua . a torrent, however sma ' . d 't declivity below' will c1c - b th barnet· an I s . f of the valley a ove e d b l nd not the dimenswns o termine the violence of the C: ac el, a urce of local deluges Th ost umvcrsa so . the torrent. e m 1 1 s they are somettmes . 1. d or ava anc 1es, a . · are land-slips, s 1 es, f k d soil or sometimes Ice called, when great ~.a sses o. roch e abne d of ' a river, e.t t lJ er by and snow, are preCipitated mtoht I 'nO' of a sub-stratum . . f Hf by t e oosem o the undermmmg o a c 1 ' h ke or other causes. by springs, by the shock of an t ea:~u~~:ra;e all the instances Volumes might be filled were we o FLOODS IN NORTH AMERICA, 193 which are on record of these terrific catastrophes : we may therefore select a few examples of recent occurrence, the facts of which are well authenticated. Two dry seasons in the White Mountains, in New Hampshit ·e, were followed by heavy rains on the ~8th August, 18~6, when from the steep and lofty declivities which 1·ise abruptly on both sides of the river Saco, innumerable rocks and stones, many of sufficient size to fill a common apartment, were detached, and in their descent swept down before them, in one promiscuous and frightful ruin, forests, shrubs, and the earth which sustained them. No tradition existed of any similar slides at former times, and the growth of the forest on the flanks of the hills clearly shewed that for a long interval nothing similar had occurred. One of these moving masses was afterwards found to have slid three miles, with an average breadth of a quartet· of a mile. The excavations commenced generally in a trench a few yards in depth and a few rods in width, and descended the mountains, widening and deepening till they became vast chasms, At the base of such hollow ravines was seen a wide and deep mass of ruins, consisting of transported earth, gravel, rocks, and trees. Forests of spruce-fir and hemlock were prostrated with as much ease as if they had been fields of grain; for, where they disputed the ground, the torrent of mud and rock accumulated behind till it gathered sufficient force to burst the temporary barrier. The valleys of the Amonoosuck and Saco presented, for m~ny mile~, an uninterrupted scene of desolation, all the bridges bemg earned away, as well as those over their tributary streams. In some places, the road was excavated to the depth of from fifteen to twenty feet; in others, it was covered with earth, rocks, and trees, to as great a height. The water flowed for many weeks after the flood, as densely charged with earth as it could be without being changed into mud, and mal'ks were seen in various localities of its having risen on either side of the valley to more than twenty-five feet above its ordinary leveL Ma~y sheep and cattle were swept away, and the Willey family n· · b h · · ' me In num er, w o m alarm had deserted their house Were destl'oyed on the banks of the Saco: seven of thei; mya ngled bodies were afterwards found near the river, buried ~L 0 |