Читать книгу The Romance of Modern Geology. Describing in simple but exact language the making of the earth with some account of prehistoric animal life онлайн

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Stereo Copyright, Underwood & U.

London and New York

A Petrified Tree

This magnificent fossil is in the Petrified Forest of Arizona; and it affords one of the most striking examples known of the solidification and petrifaction of material by the infiltration of mineral salts. The trunk is now not merely encrusted with stone: it is permeated by silica, and is, in fact, itself a stone as hard as flint.

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We have already spoken of the story which the sea writes in the annals of geology. It is a story with two plots. In the first place, the sea is always wearing away the land. In the second place, it is arranging on its own bed the materials which it takes from the land, either directly or indirectly. As a sequel to both stories, the materials all neatly ranged, packed, and folded are revealed when the sea subsides from them, or when, in process of one of those great geological changes, the origin of which we have already attempted to account for, the sea bottom is raised to become the land of a continent. The first part of the sea's belligerent story is written so plainly for all eyes to see that one scarcely need dwell on it. Every strip of coast around these islands bears witness to it.