It Lower the area ami belong to an even earlier age than of W estmarbles the and is pointed out that the marbles of Vermont lly different chester County, with their associated rocks, are essentia f,-,>m one another, and can hardly, therefore, belong to a common belt and formation; the Vermont marbles being found in a single banded and mottled of and behio' almost pure carbonates of lime, es, quartzit es, limeston s siliceou gray with -rained, appearance, tine ster marbles and slates identified with them; whereas the Westche crystalline doloconstitute a series of parallel belts and are - coarsely carbonates of lime and magnesia ) , generally of uniform i mitesdouble them that white or whitish color, and have no rocks associated with ." Vermont of s can represeni the quartzites and argillite the W estStill another opinion regarding the origin of the rocks of believes who cdiester County regions is that of Prof. I. S. Newberry, ,li;!i they date from the Laurentian age. secThe limestone beds are distributed through every geographical tion of the count v. At Sim>- Sing occur marble deposits-- very heavy largely beds which have been extensively quarried. It was, in fact, of the g quarryin the for for the purpose of employing convict labor York marble that this place was chosen as the location for the New

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State Penitentiary. The Sing Sing marble, however, although an admirable building stone for many purposes, is of comparatively coarse and inferior quality, becoming stained in the course of time by the action of the sea air on account of the presence of grains of iron pyrites. Marble is also quarried at Tuckahoe. Abundant indications are afforded of extensive and radical glacial action. " Croton Poiut, on the Hudson, and other places in the county, show evidences of glacial moraines.