Page:Geology and Mineralogy considered with reference to Natural Theology, 1837, volume 2.djvu/17

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EXPLANATION OF PLATE I.
3

As it would encumber the section to express Diluvium, wherever it is present, it is introduced in one place only, which shows its age to be more recent than the newest of the Tertiary strata; it is found also lodged indiscriminately upon the surface of rocks of every formation.


Granite.

In our early Chapters we have considered the Theory which refers unstratified rocks to an igneous Origin, to be that which is most consistent with all the known Phenomena of Geology, and the facts represented in the Section now before us are more consistent with the Postulates of this Hypothesis, than with those of any other that has hitherto been proposed. I have, therefore, felt it indispensable to adopt its language, as affording the only terms by which the facts under consideration can be adequately described.

Assuming that Fire and Water have been the two great Agents employed in reducing the surface of the globe to its actual condition, we see, in repeated operations of these agents, causes adequate to the production of those irregular Elevations and Depressions of the fundamental Rocks of the Granitic series, which are delineated in the lower Region of our Section, as forming the basis of the entire Superstructure of stratified Rocks.

Near the right extremity of this Section, the undulating surface of the fundamental Granite (a. 5. a. 6. a. 7. a. 8.) is represented as being, for the most part, beneath the level of the Sea.

On the left extremity of the Section (a. 1. a. 2. a. 3.) the Granite is elevated into one of those lofty Alpine ridges, which have affected, by their upward movement, the entire series of stratified Rocks.

Corresponding formations of Primary and Transition