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Show CHANGES OF TliE S URFACE 132 · t necessary to pro· to allow the dcrangemen bonifcrous strata, ' d Al inc chains. d oTeat continents an p t by reference to modern u~u~ it would b~ idle to controv~;1~ think they can ascend in ana1 o g:w , s ' the conJectures· oinf tohfo soeu r sys t e m · Let us, therefor1e , h . r·etrospect to the orig f the globe suffered after t le t c1r the crust o . 1 cons l'der what changes · . f rocks to whiCh we lave 1t senes o d Solidation of that an~lei 'd that before our secon ary con 1 e 1s ev1 ence ' d d adverted. Now, tler f lder date (from the old re san - strata were forme~, tho~e o :ere fractured and contorted, ~nd t ne to the coal mclusive) . . We cannot enter here mto O.S 0 • f } positiOnS. , h ften thrown mto ver Ica 1 . h 't. demonstrable, that at an epoc the o-eological d etai'1 s byw llC 1 IfS tl carboniferous sen.e s were o parts o le h b extremely remote, some sea others sunk to greater dept s e-lifted above the level of ~h~ein' no longer protected by a cover-neath it, and the former' dg t d by torrents and the waves ' t'·lly es roye . d ing of water, were par ~ad matter for newer horizontal be. s. of the sea, and supphe t d edges of the submarmc These were arrange d on. the tru. nca e d the fragments m. e I ud e d P h . anCient series, an . '1 h 11 ortions oft e more t'll retain their fossi s e s d . ono-lomerates s 1 k in the more mo ern c ol t determine the parent roc s and corals, so as to enab e. usd * o By such remodelling of the 1 were den ve · · · d from whence t 1e~ f h fi. t period increased m size, an surface the sm.allisland~ ~ t ~o::hern regions, consisting pa:tiy new land was mtroduce. mto k d partly of the newly raised of primary and volcamc roc ; a~her proofs that earthquakes carboniferous strata. A mono o l hich now regulate the d b the same aws w . )' were then governe y find that they were restrained ~vit 1111 subterranean forces, we . f G many was not agttated, limited areas, so that the Sit~ ~n l:~d was convulsed. The while that of some parts o. d Yn some cases undisturbed at older rocks, therefore! remame d in this case the strata of t1 e bottom of the ancient ocean, an 1 . tl Bristol coni-field, the • Thus for example, on tll e b an ks of t.h ot Aveodni', a mte beltew een the car bo m' t~ .r ous ' k f an age m erm tn' lime- clol?mit~~ c:eg~~:,e;:!~~ ::~~1e ~runcated edges of tl~~e cl:~!e:,nfu:~~:h :~e seen sset:~e: :nd contains rolled and angula! f'r'algmeF~to: :~curate sections illustratingther ' t · l" stone 10SSl S. b ~ the newe the characteristic. moun am- ~~~~e carboniferous series underw~nt e or~oir on the disturbances whlchf rocksd othe reader should consult the admundbl~c Conybcarc, red sandstone was orme ' l d by Dr Buckland an . J!Outh-western coal district of ~ng an ' • Geol. Trans., vol. i.1 second senes. AND CLIMAT'E, CONTEMPORANEOUS. 133 the succeeding epoch were deposited upon them in conformable position. By reference to groups largely developed on the continent, but which are some of them entirely wanting, and others feebly represented in our own country, we :6nd that the apparent interruption in the chain of events between the formation of our coal and the lias arises merely from local de:6- ciency in the suite of geological monuments •X:. During the great interval which separated the formation of these groups, new species of animals and plants made their appearance, and in their turn became extinct; volcanos broke out, and were at length exhausted; rocks were destroyed in one region, and others accumulated elsewhere, while, in the mean time, the geographical ·condition of the northern hemisphere suffered material modi:6cations. Yet the sea still extended over the greater part of the area now occupied by the lands which we inhabit, and was even of considerable depth in many localities where our l1ighest mountain-chains now rise. The vegetation, during a part at least of this new period (from the lias to the chalk inclusive), appears to have approached to that of the larger islands of the equatorial zone t. 'l'hese islands appear to have been drained by rivet·s of considerable size, which were inhabited by crocodiles and gigantic oviparous reptiles, both herbivorous and carnivorous, belonging for the most part to extinct genera. Of the contemporary inhabitants e>f the land we have as yet acquired but scanty information, but we know that there were flying reptiles, insects, and small insectivorous mammifera, allied to the opossum. In farther confirmation of the opinion that countries of considerable extent now rose above the sea in the temperate zone, we may mention the discovery of a large estuary formation in the south-west of England of higher antiquity than the chalk, containing terrestrial plants and fresh- *In many 1mrts of Gcrmany1 the newer red sandstone, and other rocks of about the same age, lie in conformable strata on the coal. In some districts, as in tho Thnringerwald, among others, thE.'re is an immense series of formations intervening bc~ween the coal and the lias; one of these groups, called tho muschelhalkstcin, wh1ch seems to have no existence in England, is of great thickness and full of orga~ic remains. See Professor Sedgwicl<'s Memoir on the Geological relations saenr1~e sm, vteorl.n aiili ., sptraurct tu1,r ep . o1f2 1th. e Magnesian Limestone, &c. Geol. Trans., second Scti. NAndt.. l BNroovn.g u1i8a2r8t,. Consid. Generales sur la Nat. de la Veget. &c. Ann. des |
