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by revolutions which have repeatedly submerged, elevated, and dislocated its framework. Disclosures of this nature- surpassing the marvellous fancies of an oriental imagination-so novel to the great crowd of men-so contradictory to the prevailing sentiments in which they are educated-have been received with no little distrust, and have exposed the geologist to no small amount of obloquy, from the parties who prefer cleaving to the tradition received from their fathers, and to the more obvious optical impressions, than to engage in any laborious exercise of the reflective faculties upon the phenomena of nature. In fact, geology has had to encounter the precise difficulty with which astronomy had to contend in its early stages-that of being antagonistic in its decisions to habitual ideas, and to the first blush of sensible evidence: for as the eye recognises the revolution of the sun, and the fixedness of the earth, while science teaches the stability of the former, and the rotation of the latter, so the idea conveyed to the mind by the Cyclopean masonry of the limestone mountains, mass piled on mass, till the height of the clouds is scaled, is that of a hard and refractory sub

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stance, which has sternly stood its ground from the era of primeval time; whereas the scientific investigator teaches, that its materials were once held in aqueous suspension, and its substance as susceptible of impression as the sand from which the tide of the ocean has just retired. Yet the proof is equally irresistible in the one case as in the other. The minute organisations which enter into the constitution of many of the towering cliffs which proudly throw back the impetuous dash of the billows, and the exquisitely delicate markings by organic structures which they present the impressions of plants, leaves, and shells, and the foot-prints of birds-proclaim with undeniable evidence the fact of a former soluble condition, and of great vicissitude having stamped its character upon them.

It is a distasteful task to the generality of mankind to unlearn. They do not willingly abandon notions that have grown with their growth, and strengthened with their strength, and struck their roots deep and fast into their "heart of hearts." Besides being mortifying to intellectual vanity to admit an error, they disrelish the mental disturbance occasioned by the breaking up of old associations of ideas, and the toil which a correct conception of

truth may require. Much of the suspicion with which the scientific have been visited, may be referred to prejudices in favour of early imbibed opinions, to which the demonstrations of science have been opposed - prejudices which are known in the pages of Lord Bacon as idola specus, the individual mind being the den to which that sagacious observer of human nature alludes; and repugnant as it is to the owner and guardian of the mental cavern to have its chambers of imagery searched, and the occupant of any niche ejected, men have been compelled repeatedly to submit to the process, however they may have resisted the attempt. A country schoolmaster may still discourse of the four elements-fire, air, earth, and water; and his boys may look up to him as a prodigy of erudition; but chemical analysis teaches us to smile at the enumeration, though old as the days of the Greek philosophers. So the antiquated notion of the earth being an extended plane, like a table, -as motionless as that household instrument, the sun coming to take his daily peep at it, like a careful watchman on his rounds,- has vanished from the face of civilised society, though supported by the impression of the senses, once deemed essential to religious faith, and defended by ecclesiastical law. It becomes us therefore, when the decisions of science are contrary to our familiar ideas, to inquire into the soundness of both, and willingly to surrender our preconceived opinions to the force of truth, and not to array prejudice against knowledge. Even did the revelations of geological inquiry not admit of common minds entertaining the evidence upon which they rest, the decisions of the actual experimentalists invite regard, on account of their number, science, sagacity, moral character, means of information, and unwearied industry in employing them. But however at variance several of its conclusions may be with the convictions gathered from the ordinary ocular view of nature, it requires but a little attentive inspection of the face of a country-its sea-cliffs, beaches, mountain sides, rocky precipices, land-slips, and ravines, connected with a very

Land-slip.

slight reflection, to apprehend the solid foundation upon. which the geologist grounds his doctrines, of changes and catastrophes in the constitution of the superficies, as well as the vast epochs of time required for the aggregation of strata: and to one who has read the record of mutation so clearly inscribed upon the surface of the globe, and has recognised its hoar antiquity as a legitimate deduction from the exist

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ing monuments of its fluctuations, the wonder is, that with the same powers of observation, the great mass in enlightened communities, until a recent period, should have remained so ignorant of the history of their terrestrial home.

The time is happily going by, for aspersions to be cast upon the geologist, as if he were pursuing an unprofitable employment, or

"Had learned the art that none might name,

In Padua, far beyond the sea."

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A fair comparison between the objects of his attention, and many of those which occupy their busy thought by day, and fevered dreams by night, who have pronounced his wisdom folly, would turn the tables upon his censors, and prove that folly must be assigned to them; while an enlightened use of his mental faculties, and means of knowledge, must be attributed to him. To visit a bed of chalk, a sandstone quarry, an erratic block, or an ossiferous cavern-to pick up shells, pore over a fossil, chip off portions of rocks, and store away the ungainly fragments in a cabinet-to examine the structure of strata, their dislocations, dip, and organic remains-to ascertain the aqueous or igneous origin of the vast mineral masses overlying the globe to detect the substances which inhere in the composition of the earth's surface, simple or combined, and become familiar with gneiss, hornblende, felspar, quartz, mica-schist, and the carbonate of lime, which gives marble to the statuarythese may seem, to the superficial observer, occupations barren alike of interest and profit, yielding only insipidity and toil to those who engage in them. But, in reality, they have relations which bring the inquirer into immediate contact with some of the grandest movements of Providence in this lower world: they may lead him, by a strict process of ratiocination, to results which will proclaim to his inward consciousness, that a wise and mighty Potentate "sits upon the circle of the earth," and that man, who is capable of "feeling after Him," is " of subtler essence than the trodden clod:" they may be so conducted as to minister to the repose of his mind upon Him whose workmanship is investigated, and impress it with those sentiments of humility and awe which are so beneficial in their influence, yet so soon effaced amid the bustle of this life's customary labours. It is assuming what remains to be proved, to say that it is in the vagueness of mere curiosity, or in the vanity of human nature, that the geologist looks abroad upon terrestrial phenomena, recurring to periods in the past far removed from the present era, and to events which appear to have no direct bearing upon our existing condition and wants. He is a part of the vast scheme of being which he seeks to explore. He indulges intellectual appetencies, which have been given him by the Father of spirits: he takes the faculty to observe, admire, and partially comprehend, into a field furnished with impressive evidences of Divine power, intelligence, and goodness; and the spectacle presented to his attention is a sublime one, and has its lessons of religious faith and practice to teach. The rudest stocks and stones that peep out of the greensward with which the soil is covered-the remains of organic life that have been buried from the light of heaven for countless ages, form the colossal megatherium to the microscopic infusoria-from delicate mosses to stately coniferæ-bear witness to a Creator, and to animal and vegetable tribes with marvellous

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Castalian Spring.

organisations, flourishing upon the earth before the present races appeared, the monuments of His skill; and while He is to be praised, for enabling man, with limited capacities, and inhabiting a spot so comparatively small, to acquaint himself with forms that have been blotted from the book of life, it is man's obvious duty, and as much to his advantage, to contemplate these works of His hands, and demonstrations of His attributes.

The acquirement of correct views respecting the condition of the crust of the earth, and the fluctuations it has undergone, is of very recent date; though several of the ancient Greek and Roman writers possessed no inconsiderable amount of geological knowledge. Strabo discussed the question of the occurrence of marine shells at a distance from the shore, and at great elevations, and offered the theory of an upheaving cause in explanation, substantially the same as that adopted in modern times. The following passage from the philosophical geographer, written more than two thousand years ago, expresses the identical proposition which forms the basis of Sir C. Lyell's introductory volume on the Principles of Geology: "It is proper," he observed, "to derive our explanations from things which are obvious, and in some measure of daily occurrence, such as deluges, earthquakes, volcanic eruptions, and sudden swellings of the land beneath the sea; for the last raise up the sea also; and when the same lands subside again, they occasion the sea to be let down. It is not merely the small, but the large islands, and not merely the islands, but the continents, which can be lifted up, together with the sea; and both large and small tracts may subside, for habitations, and cities, like Bure, Bizona, and many others, have been engulfed by earthquakes." In Lucretius, we have a description of monstrous quadrupeds, recognised as existing previous to man and the present race of animals, which might almost warrant the belief that some fossil gigantic skeleton had met his eye:

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In the fifteenth book of the "Metamorphoses" of Ovid, the poet, when detailing the Pythagorean doctrines, adduces a series of examples of that process of change, attributed by the philosopher of Samos to nature, which sufficiently separate him from the class of speculatists, and entitle him to rank with physical inquirers. The chief instances of variation enumerated are

The conversion of the sea into dry land, and the dry land into sea.

The occurrence of marine shells at a distance from the shores, and of anchors fixed on the summits of the hills.

The reduction of hills to plains, and the scooping out of valleys in the plains by the action of floods, with the transportation of their detritus to the sea.

The change of bogs into solid ground, and the formation of stagnant pools in dry places.

The opening of springs, and the damming up of rivers, as the effect of earthquakes, compelling them to pursue a new course; of which last phenomenon, the Erasimus in Greece, the Lycus and Mysus in Asia Minor, are the given instances.

The conversion of the waters of certain rivers from sweet to brackish, as those of Anigris and Hypanis.

The increase of continents, by the junction of islands, through the growth of deltas and

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