September 20, 1894] 



'NA TURE 



505 



GEOLOGIES A.XD DELUGES} 



IN" the (lays when geology was young, now some two hundred 

 years ago, it found a careful foster-mother in theoloi;y, who 

 watched over its early growth with anxious solicitude, and 

 stored its receptive mind with the most beautiful stories, which 

 the young science never tired of transforming into curious fancies 

 of its own, which it usually styled " theories of the earth." 



Of these, one of the mo5t famous in its dav and generation 

 was that of Thomas Burnett, published in 16S4, in a work of 

 great learning and eloquence. Samuel Pepys, of diary-fame, is 

 said to have found great delight in it, and it is still possible to 

 turn to it with inteiest when jaded with the more romantic 

 ficiion of our own day. 



It was the fashion lo commence these theories with chaos, 

 and chao?, according to Burnett, was a disorderly mixture of 

 particles of earth, air, and water, floating in space ; it was 

 without form, yet not without a centre, a centre indeed of 

 gravity, towards which the scattered particles began to fall, but 

 the grosser, on account of " their more lumpish nature," fell more 

 .[uickly than the rest, and reaching the centre first accumulated 

 about it in a growing heap, a heap, as we might now express it, 

 of fallen meteorites ; the lighter particles, which form fluids, 

 followed the heavier in their descent, and collected around the 

 solid kernel to form a deep ocean. This was at flr^t a kind of 

 emulsion, like milk, formed of oily and watery parti. !es com- 

 mingled, and jun as in the case of milk, there separated on 

 standing, a thick creamy upper layer, which floated on the 

 "skim-milk" below. That this really happened, the good 

 Burnett bravely remarks, "we cannot doubt." The finest 

 dust of chaos was the last to fall, and it did not descend till the 

 cream had risen ; with which it mingled loform, under the heat 

 of the sun, the earth s first crust, an excellent but fragile pastry, 

 consisting of fine earth mixed with a benign juice, which formed 

 a fertile nidus for the origin of living things. Outside nothing 

 now was left, but the lightest and most active particles of all, 

 and these "Hying ever on the wing, play in the open spaces" 

 about the earth, and constitute the atmosphere of air. 



Such w.as the earth when first it formed the abode of unfallen 

 man — perfect in form and beauty, for it was a true sphere, 

 smooth as an egg ; undisfigured by mountains, and unwasled 

 by the sea. It was unfortunately but too like an egg, 

 since its fragile shell rested on ihe treacherous waters of the 

 interior abyss, "the waters under the earth, ' and the sun over- 

 roasting, finally cracked and burst it ; the broken fragments of 

 the ruined world tell downwards into the abyss, and the subter- 

 ranean waters rushed out in a mighty flood to remain .is our 

 present seas and oceans, from which the broken crust protrudes 

 .as continents and islands. As might naturally be anticipated, 

 the bursting out of the abyss corresponds to the Noachian 

 deluge, which we thus perceive to have been profounder in its 

 origin and wider reaching in its efl'ects ilian we might previously 

 hive supposed. 'Ihis, fjr di^tiaction, we may call Burnett's 

 deluge ; of his geology we may say that it is cosmological, 

 since it endeavours to trace the history of the earth backwards 

 to its origin in chaos ; that it is catastrophic, because it attempts 

 to account for all the great features of the earth by a single 

 event which occurred suddenly and with violence ; and that it is 

 theologic, since it owes its inspiration to Holy Writ. 



.\s geology grew older it went, to school : what was the 

 name of the school is not quite certain ; some have called 

 it " Science falsely so called," others, more briefly, 

 "Inductive Science.' However this may be, the immediate 

 eflfect on the manners of young geology was very dislres^ng. 

 It grew contradictory, and was frank in the expression of 

 obnoxious opinions. One of its most irrigating remarks was 

 that the world was not made in a week, and it would appear 

 ihat at this time the relaii .ns of child and foster-parent became 

 not a little strained. Slill geology proved an apt scholar, and 

 its progress was rapid. One of the most imporlant lessons it 

 learnt was that if we want to know how the world was made, the 

 first essential is to sludy the earth itself, lo investigate with 

 patient drudgery every detail that it presents, and particularly 

 ihe structures that can be seen in river-banks, sea-cliffs, 

 quarries, pits, and mines. Thus it discovered that the solid 

 kind beneath our feet is to a large extent composed of layers 

 of sediment wh'ch were once deposited more or less quietly at 

 the bottom of ancient seas, and certain curious bodies known 

 as fossils, it concluded lo be the remains of plants and animals, 



1 Eridsh AssoTiarion .\iiircsilo worViiis men, by Prof. Soil.!*:, F.R.S. 



NO. I 299, VOL. 50] 



sea-shells and the like, which were once the living denizens of 

 these seas. 



It discovered Ihat the«e deposits \'e sn regularly one upon 

 another, that it compared them to a pile of hooks, or to a slant- 

 ing row of looks lying cover to cover ; and that in some cases, 

 at leas', the simile was not strained, will appear if we trace the 

 structure of England from Oxford westwar.'s towards Bristol. 

 We then find that Ihe thick bed of clay upon which Oxford 

 stands, lies;evenly on a series of gently sloping beds known as the 

 lower Oolites : these in like manner repose on those thin seams 

 of limestone and clay called Ihe Lia=, and these in their turn 

 upon the red beds of the Trias. It might perhaps have been, 

 expected that this uniform arnrgement would continue through 

 the whole thickness of the stratified rock«,but it was discovered, 

 and the importance of the di-'cnvery was recoeni=ed so early as 

 1670 by Bishop Steno,a man of great genius, that the regularity 

 ofthe succession is liable to interruption at intervals. Thus as we 

 approach Bristol, we encounter those beds of limestone which 

 are associated with our coal-bearing strata, and which are 

 consequently called "carboniferous"; but these are by no 

 means related to the beds we have just passed over in the same 

 manner as they are to one another — we do not find Ihe highest 

 J)ed of the carboniferous series offering its upper surface as a 

 gently sloping platform on which the trias may rest ; on the con- 

 trary, the carboniferous beds are seen to lie in great rolling 

 folds, with the tops of the rising folds absent, as it were sliced 

 off', and it is on the edges not on the surface of ihe^e beds that 

 the red trias layers are seen to be spread out. This sudden 

 change in disposition may well be called a break in the suc- 

 cession of Ihe rocks, and, as if lo emphasi*:e it and compel atten- 

 tion to it, we find it accompanied by a complete change in the 

 character of the fossils, those occurring in ihe carboniferous 

 rocks being of entirely different kinds lo those which are found 

 in the overlying beds. 



Evidently the carboniferous beds could pot have been laid 

 down in the sea in the steeply folded form thev now present, at 

 first ihey must have been spread out in nearly horizontal layers, 

 and the folded form must have been subsequently impressed 

 upon them, no doubt by Ihe action of some stupendouslv 

 powerful force. Subsequent also must have been the removal 

 of Ihe upper parts of the folds and the general planing down 

 1 which they appear lo have undergone. 



I To Ihe young geology all Ihis might seem perfectly clear, 

 but in its impulsive explanations it assumed that nature must 

 have frequently acted in a great and lerrib'e hurry : thus the 

 folding of the rocks was supposed lo have been p'oduced sud- 

 denly and violently by a sing'e mighty convulsion, which 

 simultaneously changed sea-floors into mountain chains, split 

 open the land in wide gaping ciiasms — our p-esent river valleys — 

 and with the same blow destroyed every living inhabitant in the 

 world. 

 I But the discordance between two sets of rocks is met with 

 not once only, but several times, in the stratified rocks of Ihe 

 earth's crust, and for every discordance there must have occurred 

 a corresponding catastrophe. 



These catastrophes were as wonderful as Burnetl's, and there 

 were more of them, so that at this stape of its exis'enre 

 geology was appropriately designated "catastrophic." It 

 had completely severed the apron-string", and ceased to be 

 theologic, but it still to its credit remained cosmologic. I' 

 tr.aced the earth from chaos up lo a stage when islands and 

 continents rose out of a primeval ocean, the waters of which 

 were boiling ; saw it peopled with strange and v.irious forms 

 of life, and watched it run its course, rejoicing in the sirn, 

 "chearfull, fresh, and full of joyannce c'^d," ihen pictured it 

 overtaken with disasters, shaken with earthquakes, over- 

 whelme<l by floods, and agonising in the labours of a n'^w birth 

 ("aim followed after storm, and life rejoiced afresh in a remade 

 world 10 be again destroyed. Thus, through alternations of 

 peace and strife, the earth moved on its changeful w.av, to ihe 

 crowning creation of man, who was himself a living witness of 

 the last great catastrophe of all, the N'oachian deluge. Its 

 waters covered the whole earth, lo the tops of ihe highest 

 mountains under heaven, and on their retreat they left behind, 

 as a standing witness lo their extension, great sheets of sediment, 

 supposed lo be spread out over the entire surface of the globe, 

 and appropriately named Ihe "diluvium." The diluvium may 

 be seen in most parts ofthe British Isles, except in the south of 

 England ; it consists of clays and sands, containing vast numbers 

 of curiously scratched stones. 



