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it is no other than simple mineralogy, or the science of minerals, attempting to determine, by phenomena alone, two remote and extensively important facts, pertaining to the HISTORY of this globe.

The first thought which a consideration of these pretensions awakens in a reflecting and reasoning mind, is this question:-Can mineralogy be competent to determine, by means of physical principles alone, exclusively of all historical aid or guidance, the matter of fact in those points? Can it be competent, to "conduct us to certain "notions" respecting the mode of the formation of the primitive mineral substances of this globe? or, to "decipher the historical monuments of its "revolutions?" or, to "compel the primeval moun"tains to unfold the secrets of their origin?" or, to" trace and ascertain the causes of the changes "which have taken place in them?" For, the proper sphere of mineralogy is confined to the characters and qualities, that is, to the actual sensible phenomena of mineral matter; and, can actual sensible phenomena alone supply the means of determining, with the evidence which sound philosophy and sound reason demand, the certainty of the two past facts in question?

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To this doubt, the mineral geology thus replies that it is competent to determine these two points of fact, and, with all the evidence which reason and philosophy demand; that "the happy "revolution effected by BACON and NEWTON in the

"studies of the natural sciences, was not experienced "in the science of geology until very late1;" but that, by employing the method of induction from "observation and sound principles of physics, by the

rules of an exact logic," introduced by that happy revolution; and, by adhering to the rules taught, and practised, by those great teachers; it is able to reason, securely and conclusively, from the sensible phenomena of mineral matter, to the MODE of its first formation and of its subsequent changes and that man, "who has weighed the

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planets, and measured their distances, may presume to trace the operations by which the surface "of the globe was arranged3."

This, then, is the test, by which the mineral geology desires that its own validity should be tried. Let us, therefore, apply our close attention, whilst it professes to instruct us upon those two heads by the rules of an exact logic, and on sound principles of physics; and let us first hear it upon the first head, which constitutes the BASIS of all geology, viz. the MODE of the formation of the PRIMITIVE mineral masses of the earth, comparing.

"L'heureuse révolution, que BACON et NEWTON avaient opérée dans "l'étude des sciences naturelles, ne se fit ressentir que bien tard dans "celle de la géologie."-D'AUBUISSON, Disc. Prel. p. 3.

""L'observation, les principes d'une saine physique, et les règles "d'une exacte logique."—Ib. p. 36.

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Comparative View of the Huttonian and Neptunian Systems of Geology, p. 2, 3.

it with the standard of BACON and NEWTON. The issue of the first comparison, will probably determine the degree of authority which it is entitled to command with respect to the second head, viz. the MODE of the CHANGES, or the REvoLUTIONS, which those primitive mineral masses have undergone.

CHAPTER III.

1. "FORMATIONS, (says the mineral geology,) "are the different assemblages of particular rocks "or soils, in which one and the same species eminently prevails.-These are the true UNITIES in the mineral constitution of the globe; the deter"mination of which, is the great object of geognosy'.

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-Primitive, or first formations, are those mineral formations which preceded the existence of orga"nised beings"."

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2. " In considering the globe in its entireness, and in fixing our attention upon its figure, "we shall find, that it is exactly such as a fluid

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mass, endowed with similar motion, would have "assumed; and we shall be immediately sensible of its primitive fluidity."

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3. "That the surface of the globe has been in "a fluid state, is established by very ample "evidence-which extends to the whole surface of “the earth, and indubitably proves its former fluidity. "It is proved, that the whole surface of the globe

has, at one period, been in a fluid state; and, "that from this has originated its present arrange" ment"."

' D'AUBUISSON, tom. i. p. 322, 3.

3 Ib. Introd. P. 3.

2 Ib. tom. ii. p. 3.

4 Compar. View of Hutt. and Nept. Geol. Introd. p. 3, 4, 5.

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4. There is a great class of rocks which lies "under every other, but never over any of them; "it is, therefore, the oldest, and, as far as we know, the first formed. It is denominated the primitive class. The rocks belonging to this "class have a crystalline appearance, intimating, "that they have been precipitated from a state of "chemical solution1."

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5. "

Crystallisation, is the arrangement of the particles of a body in a regular determinate "form; and it necessarily implies a previous state of fluidity, which would allow these particles to arrange themselves in positions necessary to pro"duce these forms"."

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6." As we advance towards the lofty summits "of mountains,-we arrive at strata, which shew by their crystallisation that they have been formed " in a fluid3."

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7. The superficial parts of the earth, at "least to a certain depth, must have been originally in a soft or fluid state. This fact is inferred from the shape it at present exhibits; which, as astronomers tell us, is that of a spheroid compressed at the poles. This shape it "evidently could not assume, unless to a certain depth its superficial parts were in a soft and "liquid state. The liquidity thus proved to exist "in the more superficial parts of the globe, com

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