We regret that our space prevents our laying before the reader the masterly and deeply interesting epitome of geological discoveries contained in these two chapters. The stupendous series of these revelations may be thus briefly indicated:—That countless tribes of animals tenanted the earth for countless ages before Man’s advent; that former ocean-beds now constitute the centres of our loftiest mountains, as the results of changes gradual, successive, and long continued; that these vast masses of sedimentary strata present themselves to our notice in a strangely disordered state; that each of these rocky layers contains a vast profusion of the remains of marine animals, intermingled with a great series of fresh-water and land animals and plants endlessly varied—all these being different, not only in species, but in kind!—and each of these separate beds must have lasted as long, or perhaps longer, than that during which the dry land has had its present form. The careful prosecution of their researches has forced on the minds of geologists and naturalists “the general impression that, as we descend in this long staircase of natural steps, we are brought in view of a state of the earth in which life was scantily manifested, so as to be near its earliest stages.”[18] In the opinion of the most eminent geologists, some of these epochs of organic transition were also those of mechanical violence, on a vast and wonderful scale—as it were, a vast series of successive periods of alternate violence and repose. The general nature of such change is vividly sketched by the Essayist, in a passage to which we must refer the reader.[19] When, continues the Essayist, we find strata bearing evidence of such a mode of deposit, and piled up to the height of thousands and tens of thousands of feet, we are naturally led to regard them as the production of myriads of years; and to add _new_ myriads, as often as we are brought to new masses of strata of the like kind; and again to interpolate new periods of the same order, to allow for the transition from one group to another.[20] The best geologists and naturalists are utterly at fault, in attempting to account for the successive introduction of these numerous _new species_, at these immense intervals of time, except by referring them to the exercise of a series of distinct Acts of Creation. The chimerical notion of some natural cause effecting a transmutation of one series of organic forms into another, has been long exploded, as totally destitute of proof: and “the doctrine of the successive CREATION of species,” says the Essayist, “remains firmly established among geologists.”[21] There is nothing known of the cosmical conditions of our globe, to contradict the terrestrial evidence for its vast antiquity as the seat of organic life,[22] says Dr Whewell: and then proceeds thus, in a passage which is well worth the reader’s attention, and has excited the ire of Sir David Brewster:—