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Quarterly Review.


ART. I.—Physical Description of New South Wales and Van Diemen's Land; Illustrated by a Geological Map, Sections, and Diagrams, and Figures of the Organic Remains. By P. E. DE STRZELECKI. London: Longmans. 1845.

2. Lyell's Journal of a Geologist in North America. Plates. Two Vols. octavo. London: Murray.

Maps and 1845.

THE difference between empiricism and science is this, that the empiric depends solely on his facts, as he calls them-depends on his own limited experience, his own partial deductions; while the man of science endeavours to avail himself of all the experience and all the knowledge which is to be found amongst all mankind: and in proportion as the science we take in hand is more extensive in its sphere than the subjects to which we have been accustomed to give attention, so is it necessary to enlarge our views before we dare assume that we understand it; much more before we can lay down any fixed principles by which we may venture to test-by which we may venture to regulate and classify the single and isolated facts which may break in upon us from time to time, starting up in the remote regions of these extensive sciences.

In a science like geology, which is wide as the circumference of the world, deep as the solid foundations of the earth, the experience of a whole nation, yea, of a whole generation of scientific men, may be too limited to afford sufficient grounds for laying down any fixed principles-any universal law; and, if so, the attempt to lay them down is dogmatising at the best,


and may be mere empiricism. In so extensive a science, there may be provincial-there may be national empiricism; for the empiric is not necessarily an individual: it may be a whole society of one type. No one at present hesitates in allowing that the old Wernerians formed one class of empirics, and that the Huttonians or Plutonists formed another class; and the time may come when another and larger class may be formed through an amalgamation of the former two.

Werner did much towards making us better acquainted with the external characters of minerals: Hutton and Playfair brought to light many curious effects of heat on mineral substances, coinciding very remarkably with the appearances of various classes of rocks, in the formation of which the agency of heat had not been till then suspected. But the mines of Germany were too narrow a basis for an universal system: the gunbarrels and pigmy furnaces of Hutton and Sir James Hall formed ridiculous caricatures in comparison with nature's grand laboratory, however valuable the single facts may have been which were established by their interesting experiments; like, as it cannot be denied, that many important facts were discovered by those diligent experimenters, the alchemists, in the middle ages. We apprehend that the system of geology, which is at present in vogue, rests on too narrow a basis to be permanent; for Germany and Great Britain are the only countries in which mining operations have been carried on to such an extent as to render it possible to know truly the constitution and superposition of mineral masses. Nor shall we have any confidence in the assertions which are made concerning the structure of the earth, until the results of mining operations in many distant parts of the earth have been made known; and that by men of science who have themselves collected the facts, and who can tell us wherein these facts with, or differ from, the facts which have come under our own observation.


It is only by mining and quarrying that the relative positions of strata can be ascertained in the habitable parts of the earth: for the bare cliffs and precipices of mountainous districts usually consist of one kind of rock only, and scarcely ever teach more than what is the prevalent rock of the district. A traveller, passing through a country, may readily discover its general features-its superficial character; but such observations are of no value in geology. The surface of the earth has been so much disturbed, and by such a variety of agencies, that we can draw very few inferences, from what appears above ground, concerning the rocks which lie beneath. And even the rocks

which break through the soil, are not always those which form the substratum of the district: anomalies, like the semigranitic peaks of Malvern, or like the different masses of the Wrekin and the Skirrid, occur in all countries, by which a passing traveller would be misled. It is only in the bowels of the earth that the true positions of the several formations can be ascertained: and it is only by many observations, and in distant countries, that we can ascertain whether these relative positions are merely local, or whether they are so general as to be justly considered universal-that is, universal, when not interfered with by some local irregularity—some exception to the general law.

We surely are not now needing to be taught that no system of geology can be deduced from hand specimens, or the contents of the best cabinets: these do no more than give practical tact, accuracy in perceiving minute distinctions, separating species, and distinguishing varieties from each other. In like manner, the partial and exaggerated views which are taken by those who are conversant only with a single district, or with one country, become so many impediments in the way of forming a general system-that is, a system which shall hold true in all cases alike. The rocks themselves, and their relations to each other, must be studied in situ, and on a large scale, and in many localities, before any general system, having any pretension to truth, can be formed; and since it is now well known that in different quarters of the globe these formations differ greatly in relative position, in quantity, and in character, they must be thus carefully studied, in all parts of the world, before we can be sure that any one system, even as a local system, is true, and will stand every test; for the general does test, does govern, the particular system, though the local and particular may fall far short of, and little conduce to, any general system.

Much mistake arose when the new science of geology came into notice, through the partial views of nearly all the founders of it—of all who were thought eminent, and gave éclat to the geological theories. Their opinions were formed upon facts derived from their own several localities, and they not unnaturally supposed the condition of things to be similar throughout all the earth. Werner, confident in the facts of German mineralogy, devised the aqueous theory of formation; and he founded a school of most enterprising young men, who brought to light daily new facts, all of which they held to be corroborative of the theory of their master. To them they were so, because having their minds pre-occupied with

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