Page:Great Neapolitan Earthquake of 1857.djvu/404

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CHANGE IN THE LIMESTONE—LITHOLOGICAL CHARACTER.

inarticulately-bedded, crumbly stuff, extremely like in lithological character, the white and variegated limestone beds, of great portions of the upper limestone of Roscommon, Leitrim, and King's County, in Ireland, but much more sandy and siliceous.

Such bedding as is traceable upon the surface, appears in a direction almost vertical, and although with many changes of strike, having, upon the whole, directions ranging transverse to the main axis of the Vallone; and hence, upon the whole, presenting the flat of the bedding, to the direction of the wave-path along the valley. There is no general indication of continuity of bedding or of formation, at the opposite sides of the valley, nor anything that decisively points out, whether this limestone of its flanks continues right across beneath its clay filling or not. It seems highly probable, from the general structure of the country, however, that it does so; and equally so, that limestone, breccia, and marl beds, may lie between the crumbly limestone and the alluvial clays. The more distant and higher summits, visible clearly by the telescope—particularly those on the east behind Atena—present more of the character of the hard limestone of the Tanagro. The limestone of the lateral hills is so ill compacted, and so easily acted on by air, water, and carbonic acid, that it is cavernous in every direction, and weathers into holes and pits of fantastic forms. In hand specimens, its structure frequently shows it to consist of a mass of compacted crumbs, of rather harder limestone, angular, and not much unlike in size and form, Vesuvian "lapilli," but very slightly coherent by a softer calcareous paste.

This form, gradually passes into an almost white cre-