Page images
PDF
EPUB

30

POSTSCRIPT.

on

Since this work was completed, the “ Principles of Geology,” by Mr. Lyell, have appeared ; a work of very great talent, and full of interesting research and information the secondary causes in constant action upon the earth. This able writer has, however, taken, in some respects, a new line of theory, and is as desirous of accounting for the phenomena on the surface of the earth, without the aid of any unusual or preternatural convulsion, as other Geologists have been to press into their service a constant repetition of deluges and disasters. He sets out upon the principle of Playfair, that “ amid all the revolutions of the globe, the “ economy of Nature has been uniform, and “ her laws are the only things that have resisted the general movement. The rivers “ and the rocks, the seas and the continents, “ have changed in all their parts; but the laws “ which direct those changes, and the rules to “ which they are subject, have remained inva“ riably the same.”Title Page.

Thus we find, that while Cuvier inculcates the doctrine of numerous deluges, alternately of salt and of fresh water, Mr. Lyell endeavours to account for all things without the aid of any

general deluge, though he considers local deluges as amongst the ordinary occurrences of nature, and producing violent local effects. The Mosaic Deluge appears to be looked upon either as a fable, or as a less general catastropbe, than it is usually conceived to have been; and, as a supporter of the Mosaic account of it, it is probable that I shall be classed among those physico-theological writers,” who, in the early days of science, wrote, it is true, but little worthy of saving them from the contempt with which they are here treated.

As may easily be conceived of a theory wherein all things are to be accounted for by the slow and gradual march of natural secondary causes, Mr. Lyell's system requires an unlimited period of time for its completion; and in tracing the errors into which other philosophers have fallen, he thinks there can be no wonder if such should be the case, when hundreds of years are often reckoned, instead of thousands, and thousands instead of millions. Mr. Lyell accounts for the elevation of mountain ridges, by successive up-heavings of volcanic force, small in degree, but of frequent repetition; and, having time at command, he finds no difficulty in this process.

But notwithstanding this theoretical argument in the “ Principles of Geology,” so dis

tinctly opposed by so many facts in nature; and, with regard to at least one Deluge, so totally opposed to history, and the traditions of all nations, Mr. Lyell has taken a very learned and extended view of secondary causes, and of secondary formations. On the evidences to be derived from the fossil remains of quadrupeds, however, he has encountered the same difficulties as Professor Buckland, without having succeeded in throwing any greater degree of light on the obscurities of that subject. His mode of accounting for the remains of elephants in the icebergs of the polar seas, and for the other tropical remains of animals and vegetables over the temperate and polar regions, proceeds upon the same principle, and is

open to the same glaring objections as the theories of Dr. Buckland and Baron Cuvier.

With regard, however, to the actual age of the world, and the actually short period during which secondary causes have been in action on the portions of the globe we now inhabit, we may safely refer the subject to the powerful evidence produced in such abundance, and with so much industry, by this author himself. I have had occasion in a note, in another part of this treatise (see Chapter V.) to notice the startling facts produced by Mr. Lyell, with respect to the quantity of mud daily imported into the sea by the single river, the Ganges : it is there admitted by Mr. Lyell, that even at the lowest estimate, viz. one part in a hundred, of mud, in the waters of that river, there is imported daily into the Bay of Bengal," a mass, more than equal in weight and bulk to the great pyramid of Egypt."* It does not suit the theory of Mr. Lyell to admit the correctness of Major Rennell's estimate, in which it is shewn, with much clearness, that the daily deposit of that single river, in the flood season, instead of only once, is nearly equal to SEVENTY-FOUR times the weight of that gigantic monument. If we even divide the difference between these two authors, and admit the amount to be not more than from thirty to forty times the size of the pyramid per day, and if we extend our view of a similar action to all the rivers of the earth, and then consider the comparative actual extent of the whole mass of secondary formations over the surface of the primitive globe, we shall at once perceive that such violent transporting powers, acting for a million of years, must have produced a mass of secondary formations, infinitely greater than what actually exists upon the earth, which may, probably, be considered as of not greater medium thickness than about one mile. But one million of years

is not sufficient for those who advocate the

• Principles of Geology, vol.i. p. 284.

D

view of the subject adopted by Mr. Lyell ; no author of that school has ever yet been able to bound his views within any nameable period; and we may, with much truth, transpose their own animadversion, and consider it as not very wonderful if they find themselves involved in inextricable confusion and difficulty, when they calculate upon thousands of years, instead of hundreds, and millions, instead of thousands.

« PreviousContinue »