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part of the Northern Hemisphere; and that this event was followed by the sudden disappearance of the species of terrestrial quadrupeds which had inhabited these regions in the period immediately preceding it. I also ventured to apply the name diluvian to the superficial beds of gravel, clay, and sand, which appear to have been produced by this great irruption of water.

“ The description of the facts that form the evidence presented in this volume, is kept distinct from the question of the identity of the event attested by them with any deluge recorded in history. Discoveries which have been made since the publication of this work show, that many of the animals therein described existed during more than one geological period, preceding the catastrophe by which they were extirpated. Hence it seems probable, that the event in question was the last of the many geological revolutions that have been produced by violent irruptions of water, rather than by the comparatively tranquil inundation described in the Inspired Narrative.

“ It has been justly argued against the attempt to identify these two great historical and natural phenomena, that, as the rise of the waters of the Mosaic deluge is represented to have been gradual, and of short duration, they would have produced comparatively little change on the surface of the country overflowed. The large preponderance of extinct species among the animals we find in caves, and in superficial deposits of diluvium, and the non-discovery of human bones along with

them, afford other strong reasons for referring these species to a period anterior to the creation of man. This important point, however, cannot be considered as completely settled, till more detailed investigations of the newest members of the Phocene, and of the diluvial and alluvial formations shall have taken place."

If, then, we be asked, are there no traces upon the earth of the Deluge of the inspired writings ? we can only reply, in the words above quoted from Professor Sedgwick, that none have yet been found, and that perhaps it is not intended that they ever should be found; or we may adopt the argument respecting the Mosaic Deluge contained in the following extract from Mr. Lyell, who considers that there are not sufficient geological data for inferring that instantaneous upheavement of mountain-chains, and of great waves arising therefrom, which are considered by Professor Sedgwick, to have removed the anterior incredibility of an historic deluge.

“I may observe,” says Mr. Lyell, “ that the reasoning above alluded to seems to proceed entirely on the assumption that the Flood of Noah was brought about by natural causes; just as some writers have contended

; that a volcanic eruption was the instrument employed to destroy Sodom and Gomorrah. If we believe the Flood to have been a temporary suspension of the ordinary laws of the natural world, requiring a miraculous intervention of Divine Power, then, it is evident that the credibility of such an event cannot be enhanced by any series of inundations, however analogous, of which the geologist may imagine that he has discovered the proofs. For my own part, I have always considered the Flood, when its universality, in the strictest sense of the term, is insisted upon, as a preternatural event, far beyond the reach of philosophical inquiry, whether

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as to the causes employed to produce it, or the effects likely to result from it. At the same time, it is clear, that they who are desirous of pointing out the coincidence of geological phenomena with the occurrence of such a general catastrophe, must neglect no one of the circumstances enumerated in the Mosaic history, least of all, so remarkable a fact, as that the olive remained standing while the waters were abating *

We trust enough has now been advanced to convince the most timid that there is nothing to be feared for the cause of revealed Religion from the investigations of geologists, though they ascribe to the earth a higher antiquity than has been supposed to belong to it, in consequence, as we conceive, of an erroneous interpretation of the first two verses of the Bible; or, though they declare that they have not seen, on the earth's surface, any traces of a general deluge. No uneasiness is now felt, because the language of Scripture, with respect to astronomical phenomena is not in accordance with the present state of our knowledge respecting the universe. The explanation offered, in that case, by commentators on the Bible, is that “the sacred writers were inspired to speak of natural things with philosophical exactness, but were left to use popular language, and to discourse of them according to their appearancest," and the only reason that any alarm is felt at the wonders brought to light by Geology is their novelty. When they shall have had the sanction of another century, or even less, they will not be deemed more dangerous to religion than the discoveries of Newton.

We shall not now enter into further discussion respecting this diluvial gravel, because it is a subject which will demand a separate chapter, before we close this series. The subject, moreover, is at present undergoing much investigation, and discoveries are daily brought to light which promise, eventually, to lead to a solution of this difficult question; which is a question of much interest, because this diluvium is the first deposit we meet with in the descending series, and because its origin and history involve another important and interesting question, namely, whether causes now in action, and acting with no greater intensity than at present, are adequate, if sufficient time be allowed, to have produced all those changes on the surface of the earth which have taken place in past ages.

We shall now merely state our dissent from the theory, which attributes the dispersion of this gravel to a succession of waves, caused by the rise of mountain-chains, and to that theory which supposes it to have accumulated, during a long-protracted epoch, at the bottom of the sea, subsequently laid dry, either by the slow elevation of continents, such as appears to be now going on in Scandinavia, or by more violent subterranean movements, acting with unequal intensity, which others have recourse to in order to account for the different heights at which this gravel occurs. We shall, at the same time, place on record our conviction, that some unknown cause, not now in action, produced a violent rush of the ocean, from the north, over a great part of the northern hemisphere, at a period when the leading geographical features

* Principles of Geology. 4th Edition, vol. iv., p. 219.

+ Scott's Bible. Note on Genesis i. 16.

of our present continents were established, when the waters were inhabited by the existing species of Molluscæ, and when a large portion of the mammiferous inhabitants of the land belonged to extinct species, or to species only inhabiting the warm regions of the earth, and which disappeared suddenly with this catastrophe. But, while we contend that by this violent inroad of the sea, fragments of marine shells, of existing species, were lodged on the surface of previously-existing land at the greatest height* at which they have hitherto been found in this tumultuous deposit, we by no means deny that this inundation may have been accompanied and succeeded by slight and local elevations of the land; so that in one place, on the coast, the diluvium shall be found resting on an ancient beach, now seventy feet above the level of the sea; and in another case, likewise on the coast, shall be covered at about the same height by a thin deposit, containing marine shells, which seem to have lived and died where they are found.

The evidence on which these opinions are founded will be reserved for a subsequent part of this series; and there is good reason to hope, from the investigations now in progress, that in the mean time, the question will be decided ; and that either our views above stated will be confirmed, or will be proved to be erroneous, in which latter case we shall endeavour to read our recantation with the same frankness which reflects so much honour on the illustrious geological chiefs whose declarations we have quoted.

We have now concluded the introductory part of our work. If we followed the usual course pursued at the commencement of an elementary treatise on geology, we should enter into a history of the rise and progress of the science, beginning with an account of the cosmological opinions of the Egyptian priests, of the Indian Brahmins, and of the philosophers of Greece and Rome; introducing, as a matter of course, that hacknied quotation from Ovid, -so hacknied, that we do not remember to have opened any introduction to Geology in which it did not occur,

Vidi factas ex æquore terras

Et procul a pelago conchæ jacuere marinæ. We should then proceed to show how, when the Roman empire was overthrown by barbarians, Geology-—such as it was—took refuge in Arabia ; and how, on the revival of learning in Europe, it first re-appeared in Italy, whence we should trace its progress into Britain, France, and Germany. We should expose the folly, though it passed for wisdom in its day, of the cosmological dreams of Burnet, Whiston, and Buffon. We should show how Werner advanced, and how he retarded, the progress of geological knowledge, and should enter into a history of the controversies which agitated the rival schools of Freyberg and Edinburgh ; in which the names of Neptune and Vulcan, of Werner and Hutton, were the watchwords and the rallying cries,-controversies which, to the scandal of science, were conducted, not in the calm spirit of philosophical inquiry, but with all the warmth, and intemperance, and bitterness, of a borough election, or a vestry squabble. We should then

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* Moel Tryfan, in Caernarvonshire, 1392 feet.

detail the labours and noble generalizations of Smith and Cuvier, and advert to that grand epoch in the science, the formation of the Geological Society of London ; when, wearied with the Neptunian controversy, geologists were convinced that the time was not yet come, when they could form a true theory of the earth; but that they must be contented, for a long time, to devote themselves to the observation of facts and the accumulation of data for future generalizations; and we should then point out the mighty results which have followed from a steady perseverance in this system, during thirty years, so that the progress of Geology has, by these means, been greater, during that period, than during the three centuries which preceded it. But to commence a work professing to teach the elements of Geology, or of any science, with a history of its rise and progress, appears to us inconvenient, to say the least of it, because it supposes, in those who are addressed, a certain previous acquaintance with the very subject they require to learn. Our object is to guide our readers into the plain and straight-forward road to geological truth, by setting before them the real discoveries of the science; and, surely, that object is not likely to be advanced by first leading them aside into every by-path of error in which they can possibly lose their way, recounting all the absurdities into which men fell, when, giving rein to the imagination, they constructed systems of cosmogony upon the foundation of a few ill-observed facts, and often without the observation of any facts at all. Our object is to exhibit the amount of light at present possessed by geologists, and it would be but a waste of time to show how, and how long, they groped about in darkness before they found that light.

We agree with Professor Phillips that “the history of the progress of opinions in Geology may be useful as a warning to men advanced in geological inquiries not to reason upon assumptions while facts remain to be explored, and to repress that impatience of spirit, which ever seeks to anticipate observation by the efforts of invention; but that the student ought, if possible, to be kept in impartial ignorance of these conflicting hypotheses which are apt to fascinate the young and imaginative mind.” We shall, therefore, defer for the present, or wholly omit, a history of the rise and progress of Geology; and in our next number shall proceed to the consideration of the materials of which the earth's crust is composed, and of the order in which they are arranged.

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THE GREAT EARTHQUAKE IN CHILE, IN 1835.

BY ALEXANDER CALDLEGGH, Esq., F.R.S., &c.

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The phenomena attending this great disturbance of the surface of the earth have been so varied, and the extent of its effects so considerable, that I should almost deviate from my duty if I did not endeavour to

and transmit to the Royal Society some account of a convulsion which has laid in ruins three provinces, and caused incalculable damage to the southern part of this country. I am the more inclined to take this step, from a happy concurrence of circumstances having drawn several scientific observers to Concepcion shortly after the catastrophe, who have obligingly confided their notes to me. I trust, therefore, the Royal Society will not consider that I am about to trespass upon its time.

An idea, in some degree fanciful, prevailed for some time after the conquest of these countries by the Spaniards, that these convulsions of the earth's crust occurred at intervals of a century; afterwards it was supposed that about fifty years was the term which usually elapsed between great shocks; but, since the commencement of this century, the repeated catastrophes which have occurred, especially in the years 1812 in Caraccas, 1818 in Copiapo, 1822 in the province of Santiago, 1827 in Bogota, 1828 in Lima, 1829 in Santiago, and 1832 in Huasco, have prepared the minds of the inhabitants to expect at all times these frightful oscillations of the earth, which, although they cause little sensation at first, after some time affect the nerves in a manner not easy to account for by ordinary causes. That they happen at all times and in all states of the atmosphere, seems clearly decided. The finest weather, and the most variable, equally prevail at the moment; but many are the fancied signs hy which the coming earthquakes are predicted, and in the faith of which the inhabitants confide, as they think their experience bears them out. While some place great confidence in rats running violently over the ceilings of the

room,
others
prepare

for a shock when they observe the stars twinkling more than usual, and all fears are removed when much lightning coruscates in the Cordillera. As far as my own observations go, little reliance can be placed on the two former prognostics; something more certain seems to be due to the latter. A few hours previous to the earthquake which I am about to describe, immense flocks of sea-birds proceeded from the coast towards the Cordillera, a circumstance which occurred prior to the great shock of 1822; and it is affirmed by too many respectable persons not to be entitled to some degree of credit, that on the morning of the convulsion all the dogs disappeared from Talcahuano.

The summer in Chile had been rather colder than in preceding years. The mean of the thermometer in Santiago (two thousand feet above the level of the sea) for the months of January and February was 72° of Fahr. The mean of the barometer for the same period was 28.25, which is about one-tenth of an inch below its usual height.

From the 1st of February the barometer was unusually low in Santiago; and on the 14th, six days prior to the earthquake, the baro

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