Show M eighty aty falls of niagara ni agara are crumbling each year tho the mighty falls of niagara are crumbling year by year as thousands of tons of rock crash from tho the lip of the gorge ry by the year the waters will have completely worn away the falls and there will bo be only the I 1 IQ galle kllc river running down a cascade dotted bed from lake erie eric to the great gorge of niagara the recent fall of tons of rock was symptomatic of the die gradual er erosion oslon but this incident was only one OBO of a series of crashes that began thousands of years ago nature Is a sculptor who never stops working and one of her greatest molding and remolding weapons la Is water visitors now cow see two cataracts the horseshoe talla falls on the canadian side alde and tho the smaller Arn american erlean falls but once there was only one cator cataract ocL geologists estin into that niagara falls ts Is years old ironically the process of nature that formed the falls Is now working steadily bw but with almost inconceivable slowness to level then them the recent crashing of BO 80 OW tons of rock was only one comparatively tiny step in this never ceasing process in ono one wa way y the manner of de destruction used by nature in demolishing niagara falls la Is anu unu unusual ual ill all the cataracts oh the earth have been formed by tho the of roca by writer water the sand and gravo gravel usually swept along in the water helps in the cutting work aheu there Is a tilt OR in the river alver bed or different kinds of rock roch present cite cas codes and some sometimes tImen waterfalls aft t created but tho the water lu fri niagara river lowing froni from lake eric brie Is remarkably mar mor kably clear in it there Is practically no sand or gravel scientists have discovered that the top layer of tile the escarpment to Is ot of hard dolomite with soft shale beneath this explains why large larga pieces odthe top rock roch brenk off the water erodes the shale gradually tearing the support tiova from under the dolomite which then crashes aslica cr down dow n but it brenka breaks off in such a way that the walls walla of the falls are left jett unimpaired as yet hut but little by little the dolomite nt at the crest which forms forma the he lip over which the lie great lakes pour their stupendous excess water supply Is disappearing though it la in difficult to estl estimate mate the ant ante nt at which the wall IB 18 receding and the gorge at the same fame time la in lengthening scientists set the figure at 87 37 feet per year this Is how they arrive tit nt the conclusion that it will take alio until the year before the 10 miles of rock between lake lahe Erie arc completely broken down |