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Show EVENTS JN THR UTSTORY OF 1'IIE PBIUOD OF DHY LAND. 21 3 the rains had fallen on the country long enough to carry out ten th0usand feet of rocks, tho extension of these beds to the south, which were cut away, and yet before-the overlying Carboniferous rocks were formed as sediments of sand and triturated coral reefs, and ground shells and pulverized bonos, some interesting events occun-ed, the records of which are well preserved. This region of country was fissured, and the rocks displaced so as to form faults, and through the fissures floods of lava wore poured, which, on cooling, formed b~ds of trap, or greenstone. This greenstone was doubtless poured out on the dry land, for it bears evidence of being eroded by rains and streams prior to the deposition of tho overlying rocks. Let us go down again, and examine tho junction between these red rocks, with their intrusive dikes and overlying beds of greenstone, and the crystalline schists below. We find these lower rocks to be composed chiefly of metamorphosed sandstone and shale , which have been folded so many times, squeezed, and heated, that their original structure, as sandstones and shales, il; greatly obscured, or entirely destroyed, so that they are called metamorphic crystalline schists. Dame N atnre kneaded this batch of dough very thoroughly. After these beds were deposited, after they were folded, and still after they were deeply eroded, they were fractured, and through the fissures came floods of molten granite, which now stands in dikes, or lies in beds, and the metamorphosed sandstones and shales, and the beds of granite, present evidences of erosion sub equent to the periods just mentioned, yet antecedent to the deposition of the non-conformable sandstones. Here, then, we have evidences of another and more ancient period of erosion, or dry land. 'rln·ee times has this great region been left high and dry by the ever shifting sea; three times have the rocks been fractured and faulted; three times have floods of lava been poured up through the crevices, and three times have the clouds gathered over the rocks, and carved out valleys with their storms. The fu·st time was after the deposition of the schi ts; the second was after the deposition of the red sandstones; the third time is the present time. The plateaus and mountains of the fir~t and Aecond periods have been destroyed or buried; their eventful history i!3lost; the rivers that ran into the sea are dend, and their waters are now rolling as |