this, the too common error of immature philosophyhasty deduction from limited observation:

"Each claiming truth,

And truth disclaiming both,"

like the dogmatical asserters of the colour of the chameleon, they were both right to a certain extent, as we shall see hereafter that each of the causes for which they contended, have been active in the production of the terrestrial phenomena; but both were wrong in their sweeping generalizations. Their views, moreover, were confined to the mineral structure of rocks-the chemistry of the science; modern geologists have discovered and adopted a less fallible test-the organic contents, a principle which was first recognized and practically applied by Smith,* in the arrangement of the strata and construction of his Geological Map of England, which has attained for him the proud appellation, ceded by universal consent-of "Father of English Geologists."

* At the meeting of the "British Association for the advancement of Science," held at Oxford in 1833, the gold medal reserved for the great luminaries emanating from this seat of education, which dazzle by their learning or benefit by their discoveries, their fellow-men, was awarded by the University, with a liberality that does it honour, to this veteran of geology, who though destitute of the advantages of education, and moving in the humble rank of a land-surveyor, by his own unaided efforts had earned the laurels, which in the presence and amid the plaudits of the illustrious in science from all parts of Europe, were now wreathed upon his silvery hair. A splendid instance of the reward of perseverance, and a powerful stimulus to the exertions of those to whom Nature has imparted a scientific taste, but Fortune has denied her advantages.

In tracing the progress of science, it is lamentable to observe the extraordinary ignorance of men whom the world have called great, as to the causes of many natural phenomena, with which we are so familiar. Voltaire, for instance, who has been all but deified by the French, to whose dwelling* pilgrimages are performed as to the shrine at Mecca, who presumed to arraign all the existing knowledge upon science, religion, and government, with the most perverse tenacity, insisted that fossil shells found in the earth were lusus naturæ, creations of Nature in her sportive mood-that oyster shells found in high situations on the Jura mountains might have been the scallops worn in the hats of pilgrims, or were probably left there by the Romans, who are known to have had a taste for oysters ;—that vegetable impressions in rocky strata, were not those of real plants; and that the bones of a rein-deer and hippopotamus found in his time near Etampes, proved merely that some lover of curiosities had once preserved them in his cabinet!

Geology, as at present understood, may be said to be a species of history-the physical history of the great globe we inhabit-a sort of antiquarianism which takes cognizance not of ancient coins, broken columns, and antique inscriptions in order to determine the periods and circumstances of revolutions and remarkable eras in human affairs, but investigates the great physicalrevolutions which our planet has undergone-events of which it finds indelible records, immutable archives, the most infallible testimony, in the monuments and

* Ferney, near Geneva.

relics of former times preserved in the mineral masses of which its exterior is composed. An inquiry which starts where human records begin to be obscure, and carries back the imagination through successive eras, to a point in the infinity of the past which the mind can scarcely contemplate-a period coeval with the origin of the earth. It exhibits the surface of the earth as having been subject to a series of extraordinary and violent changes-of sudden and mighty revolutions. It details "the war of elements and wreck of matter," the successive destruction and reproduction of this fair scene of man's abode, and innumerable races of animals, ere he, the self-styled "lord of creation" had assumed dominion upon the earth. As in the history of nations, we observe a gradual developement of the human faculties-a progressive emergence from barbarism, in which most civilized nations have had their origin, to that intelligence which afterwards distinguished them, so in Geology, we discover a remarkable succession in organized beingsan apparent gradation from animals of a simple to those of a complex structure, and by ascending the series we arrive at a period anterior to the existence of life upon the earth when it "was without form and void, and darkness rested upon the face of the deep." The earth itself, like society or an individual, appears to have passed from infancy to adolescence, from adolescence to maturity, from maturity to old age, which her present feeble energies, compared with her pristine vigour, seem to indicate.

The key to this long-concealed volume of nature, and to all its mystic revelations, is the extraneous fossil, (as it is termed,) the organic remains embedded in the

solid framework of the globe. By means of these, we are enabled to arrange the apparently innumerable strata into certain orders and classes, and assign to each a definite epoch, or period of formation; and hence establish the extraordinary fact that there is throughout these mineral masses an invariable order of superposition, which in the numberless derangements and convulsions which have shaken the earth to its centre, has never been inverted: that this order of superposition is not confined to this or that locality, but is essentially the same in the old world and the new, from the arctic to the antarctic circle; as far at least as observations have at present extended.

The discoveries of Geology, like those of Astronomy, are completely at variance with our preconceived ideas, and in some cases opposed to the evidence of the senses. Until it was proved by demonstration, it was inconcievable, that the sun which rose and set and appeared constantly in motion, actually stood still: so the mind is indisposed to believe that the solid earth on which we tread, on which innumerable generations of men have lived and died, and our cities have stood from the earliest times, has been by turns, perhaps, the bed of a sea, the bottom of a lake, or matter ejected from beneath by volcanic agency. At one period buried beneath the dark abyss of the ocean, at another smiling with verdure on its shores the abode now of sterility-now of fertility now of marine and now of terrestrial animals and plants. Yet even so is it with almost every portion of what we now call terra firma, which is, in fact, one vast sepulchre of animated beings! The highest mountains have not escaped the general fate-the "everlasting hills" can no longer with propriety be cited as the emblem of immutability.

What, short of actual demonstration, would convince us that the tops of the highest mountains in England once formed the bed of the sea? and that strata now buried hundreds of yards beneath the surface were once elevated above its waters? But we have unquestionable evidence of this mighty boulevèrsement records as clear as any that Herculaneum and Pompeii can exhibit of their former condition. The insignificant little specimen, of which the engraving (1) in the margin is a representation, is a fossil shell, (once an inhabitant of the ocean) from the top of Snowdon,

1

2

the highest mountain in Wales, broken with my own hands from myriads of others in the mass of limestone * which caps its summit. The other engraving (2) represents a specimen of the vegetable productions which adorned the hills of the primeval world (perhaps subsequently to the upheaving of the ocean deposit of which the specimen just described is a relic) disentombed from the bowels of the earth at a depth of one thousand feet beneath its surface in this County !+ Now the evidence in this case is

*The occurrence of this limestone on the apex, the extreme point of this mountain, while its mass is composed of older rocks destitute of organic remains, is a remarkable feature in the Geology of Wales.

+ Leicestershire. From the Ashby-de-la-Zouch coal-field.