GEOLOGY. 



GEOLOGY. 



received physical theorem*. Stnbo proposes to account for thane 

 and other phenomena by the general ipeoulation that the land, not 

 the sea, is lubject to changea of level, and that such changes more 

 easily happen to the land below the Ma, ' because of its humidity.' 



The action of ./Etna in moving the shore* of Sicily and Italy in 

 spoken of in a familiar manner, and a long description of phenomena 

 bearing on the discussions succeeds, in which the opinions of many 

 author* are quoted. 



Fifteen hundred yean elapaed after the era of Strabo, without 

 adding anything material to the stock of geological facts, or the 

 limited range of rational theory ; for, excepting the work of Omar 

 (10th century), in which the phenomena of ' new lands,' aud marine 

 shells found inland, are referred to a ' retreat of the sea,' there ia 

 not, on the inbject of geology among the Arabian writers, even the 

 usual amount of comment on the writer* of Greece and Home which 

 characterise* the literary effort* of the learned Moslems. (Lyell, 

 ' Principle, of Geology.') 



In modern time* Italy, the fruitful mother of modern physical 

 science, offered in her volcanic cones, ranges of mountains, and shelly 

 marl* at their bases, the most attractive points to the intellectual 

 activity of the precursors and contemporaries of Galileo. 



So recent are sound views of the true nature and relations of the 

 organic form* buried in the earth, that it is not very difficult for 

 English geologists to imagine the fierceness of the contest in which 

 Fracastoro (1517) was involved, to defend his opinions that the 

 ' formed stones ' (ss they were afterwards termed in England) were 

 not ' lusus naturae ' produced by a ' plastic force,' but really the 

 remains of fishes, molluscs, Ac. ; and that they had not been rudely 

 scattered over the surface by the Noachian flood, but buried at great 

 depths by a more regular operation of water. These important 

 assertions were the subject of controversy for nearly two centuries 

 in Italy ; and in establishing the true nature of the organic remains, 

 Cardano, Colonna (1666), and Scilla (1670) overlooked or disregarded 

 the more serious and more seducing error of ascribing their iuhu- 

 niHtion in the earth to a general deluge. Georgius Agricola (1546) 

 adopted the wrong view of the origin of organic fossils : but Steno 

 (1669) of Copenhagen, opened a new line of inquiry, by noticing the 

 succession of rocks; distinguishing some as having been formed 

 before the creation of animals and plants ; insisting on the original 

 horizontal position of the strata ; the proof of violent movement of 

 the crust of the globe, afforded by the now inclined position of such 

 strata in mountainous countries ; and the variations of condition to 

 which the surface of Tuscany had been exposed, by repeated over- 

 flows and retirements of the sea. (Lyell, ' Principles.') 



Scilla' s masterly work on the organic remains of Calabria, pub- 

 lished both in Latin and Italian (' La Vana Speculazione disingannata 

 dal Senso,' 1670), may be considered as closing the long dispute in 

 Italy, among men of philosophical minds, on the subject of the 

 nature of organic fossils. Its course was comparatively very short 

 in England, for Plot (in 1677) is almost the only writer who really 

 and heartily embraced the doctrine of an occult cause, to escape 

 from the consequence of admitting the true origin of the 'formed 

 (tone*,' and Scilla'* work was abridged for the 'Philosophical 

 Transactions' in 1605-6, by Dr. Wotton. Lister's early views on 

 the matter (1678) express a doubt-, arising from knowledge ; he saw 

 that the fossil-shells were different from the living types, and pro- 

 posed the alternative of a terrigenous origin, or an extinction of 

 species. Ray (1692) on ' Chaos and Creation,' Woodward's ' Natural 

 History' (169$), Scheuchger's 'Herbarium Diluvianum,' of the same 

 date, afford proof of the victory gained by the observations of 

 naturalists over the closet speculations of metaphysicians, on the 

 origin of fossil-shells in most parts of Europe ; and indeed, in France, 

 Paliasy's lectures and writings (his last publication bears the date of 

 1580) may be said to have established the truth contended for. 



The victory was unproductive. In consequence of coupling with 

 the obvious truth a fatal and fundamental error, the shells and other 

 exuvia of the sea were maintained by Woodward and a host of 

 contemporaries and follower* to have been brought upon the land by 

 the ' universal deluge,' a* all writers except Quirini (1676) agreed to 

 term the Noachian flood. This error might speedily have been swept 

 away by the early arguments of Palissy, the investigations of Steno, 

 and the striking generalisation of Lister ; but that, unhappily, from 

 a philosophical question, it became a theological argument The 

 fossil -shell* far from the sea were held to be physical proofs of the 

 truth of the Mosaic narrative ; and the occurrence of these shells at 

 various depths and heights, and in rocks of different kinds, only 

 furnished additional arguments in favour of the violence of that 

 flood, which not merely was supposed to bare covered the mountains, 

 but to have entirely broken up and dissolved the whole frame-work 

 of the earth, aud to have deposited the materuils according to their 

 relative gravity. In vain bad Hooke, Ramazzini, and Kay, previous 

 to 1700, protested against the absurdity of this hypothesis, which 

 Leibnitz appears to have despised ; it was reserved for Mom (1740), 

 I'.. n|.. n (1749), LiniiKiis (1770), and \VhiU-hurst (1792), to hasten its 

 banishment from philosophy ; but even at thin day there are persons 

 who from time to time revive the discussions of the 16th century, as 

 a point of importance in Christian theology. 



To account for the drynem and elevation of the countries where 



fossil shells occur, there are but two hypotheses : the shelly bed of 

 the sea ha* been raised, or the ocean ha* abandoned it* ancient place. 

 Many of the Italian geologist* adopted the former view, and in con- 

 sequence repeated the opinion* and reasonings of Strabo, with the 

 ad vantage of referring to the elevation of Monte Nuovo near Puzxuoli, 

 in 1538, and Santoriuo, 1707 (Majoli, 1597 ; Vallisueri, 1721 ; Laxzaro 

 Muro, 1740). The better order of English writers (Hooke in 1668, 

 Kay in 1692 earthquakes were then frequent in Europe) adopted 

 the same views ; and Hooke in particular presented the phenomena 

 of earthquakes and volcanoes in the form of a general speculation, 

 which served to direct the opinions of subsequent systematisU like 

 Whitehurst 



None of the philosophers who were concerned in establishing the 

 truths connected with organic remains were seduced by their success 

 into the vanity of proposing any general hypothesis on the formation 

 of the earth. But this creditable modesty, so characteristic of 1 1m 

 spirit of induction which animated Fracastoro, was not at all imitated 

 by the fanciful diluvialists, who followed in the wake of Woodward, 

 Unmet, Whiston, Catcott, and others. To determine whence came 

 the water which held at once in suspension the whole of the e\ 

 parts of the globe, and whither it retreated, was necessary to help 

 out their extravagant proposition. 



No ordinary hypothesis would meet these formidable problems, 

 and if we recollect that in answering them it was further required 

 to adopt views which should not trench on the arbitrary notions then 

 entertained as to the meaning of certain passages of Scripture, we 

 shall be disposed to regard even the monstrous violations of physical 

 truth which appear in the hypothesis of Burnet Woodward, and 

 Whiston, without surprise. Omitting minor circumstances whirli it 

 would be useless to particularise, Burnet, Woodward, and their 

 followers, agreed in adopting the notion of an interior abyss below 

 the crust of the earth, as the general reservoir from whence the 

 waters rushed to cover the earth, and into which they again with- 

 drew after the diluvial devastation was completed. \Vhistou, who 

 was far better versed in physical science than either of the others, 

 introduced in addition the notion of extraneous force ; he brought a 

 comet to envelop the earth in its misty tail, to cause violent rains, 

 raise vast tides in the internal abyss, and thus effectually destroy the 

 external crust of the planet It appears probable that mankind 

 seldom permit their imaginations to take such dangerous flights 

 without necessity ; the hypothesis is made to suit the conditions of 

 the moment, and the chief error consisted in including among these 

 conditions a narrow aud unreasonable interpretation of the Mosaic 

 narrative. 



The diluvial hypothesis has been sufficiently traced to its natural 

 consequence a monstrous violation of the laws of nature; another 

 general view, first distinctly stated by Vallisneri (1721), has been the 

 source of long-continued errors. Struck by the general diffusion of 

 marine fossils, he supposed the ocean to have once extended over all 

 the earth, and to have gradually subsided, leaving everywhere the 

 traces, not of a violent flood, but of the quiet super-fluctuation of 

 water. Perhaps Vallisneri found this notion in his travels ; at any 

 rate, the notion of a universal subsidence of the ocean appears to be 

 the German element of geological hypothesis, for Werner made it the 

 basis of his so-called theory of the earth, and thus obscured with a 

 physical improbability the important truths which he had established 

 concerning the succession of strata. 



Starting from an entirely different point, Leibnitz (in 1680) pro- 

 posed one of the most general contemplations which has ever 

 appeared in geology. He commences with the concentration of the 

 mass of the globe in a state of great heat ; accounts for the funda- 

 mental primary rocks by the refrigeration of the surface, and explains 

 the violent action of water upon them by the collapse of this crust 

 on the contracting nucleus. Sedimentary strata are the natural 

 consequence of these watery movements subsiding to rest, and by the 

 repetition of the phenomena such features are imparted to the earth 

 a* to insulate many of the later deposits, and render it necessary to 

 be prudent in determining whether local or general agency has been 

 concerned in producing them. It would be difficult in general terms 

 more clearly to announce views now prevalent among those who 

 contemplate geology in connection with physical science. Cordier, 

 Von Buch, and I)e Beaumont have endeavoured by this speculation of 

 Leibnitz to explain some of the principal phenomena of geology 

 the elevation of mountains ; but the merit of Leibnitz's theoretical 

 views was little regarded in England till Mr. Conybeare explained his 

 views to the British Association at Oxford at its first meeting in that 

 city in 1833. 



The effect of Laplace's and Fourier's theorems on the operation of 

 interior heat have been augmented by Mr. Hopkins's labour.* 

 the grand views of Sir W. Herschel as to the constitution of the 

 universe have been applied to the history of the earth bv Sir Hvnry 

 l)e la Heche. 



In the works of Kay (1692), and Hooke (1688), we may trace the 

 revival of another general speculation (that of Pythagoras), which, 

 instead of deducing the leading geological appearances from some 

 primal condition, with Leibnitz, suppose* the essential condition of 

 the world to be one of continual change, and assigns to modern 

 causes in action a measure of force capable of producing, in a sufficient 



