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Show CHANGES OF TilE SURFACE 130 . d' enous quadrupeds, . dimensions, appear .t o. posseds s . ndo tlhlle tgm ore strt·1 n ·n g, w h en mex cept tl 1 c bat.' and tins 1S 1re n eieex tremt' tY of New Zealand we rcc.o llect that the nort lern th of the climate must 34o here the warm L stretches to latitude . , w evelo ment of organic lif~. ast1 y , gt. e a t1y fa' vour the pbro lificd t.ds coverpe d of a pure lacustrm.e forma. 1. nstance has yet een 1 h ·11 there are some mstances nt o 'f ra . a t oug h d 1. on of the carbom erofu s e1 ' ater, wh t'c h may have been was e of shells, apparently resdl-; ot by any means imply a con-in by small streams, an o d n All circumstances, therefore, siderable extent of ~ry lanl. baqueous character of the 1 IOn ·-t le su Point to one cone us ' . . f the calcareous strata over the contmmty o . . h igneous products- . f their orgamc remams-t e h rme nature o h b vast spaces-t e m.a. the mechanical rocks-t e a sence basin-shaped disposttlon of d drupeds-the non-existence · ·1 d of Ian qua fl of large fluvtatl .e an t ta-th e m. su lar character o. f the ora, of pure lacustr~ne s ra derful harmony to estabhsh the pre- -an concur with won h llemisphere of a great ocean, 1 t the nort ern . f valence throug lOU • 1 . If we seek for pomts o ana-interspersed with small Is. es. must either turn to the . t f thmgs we I logy to this sta e o ' bmarine or insular vo canos 'fi d · ts numerous su b . north Pact c, an 1 d New Guinea, or, in order too .tam between Kamtschatka an th coralline and shelly hme· a more perfect counterpart toh' el os of the south Pacific, l re the arc lpe ag stones, we may ~xp o d South America, where volcanos are not between Australia an l J!, consisting in great part of . d here cora reeLs, . e i wantmg, an w d over an area not llller or, per-compact limestone, are sprea l us rocks though we sup· f ient ca careo ' . haps, to that o our nne f th lakes of North Amenca to Pose these to be prolonged rom e central Europ. e * .h ever d em.e d , that when our ol de st co·n - No geologtsts ave d reat continents were wantmg chiferous rocks were produce ' g . . . ntinued line of coral reef seven h u ndred 'mnetale s tInt 11< Captain Kmg found a ~ E st of Australia towards New ~tu ir we 1 gth stretching from the . . coa din in all thirty mtles. ;:, i;terrupted only by a few in~"'al:~ n~e •;::: • .u; hi" and Socioty ~~;·.: Pass from these calcareous forma wns b . e reefs . and Captain Beecbey tn o 1. 1 ds and su marm ' · · progress, find a succession of cora lS an o he found the same formabon m ea me that in Ducie's Isle, W. loug. 1201, e growing at the depth of one hun: n ::ldl t here be ascertained that the cora s wer t limestone constitutes a large po o eigltty feet. He also observed that compac of recent reefs. AND CLIMATE, CONTEMPORANEOUS, 131 in the temperate and arctic zones north of the equator; but they have even gone farther, and l1ave been disposed to speculate on the universality of what they termed the primeval ocean. As well might a new Zealander, who had surveyed and measured the quantity of land between the south pole and the tropic of Capricorn, assume that the same proportion would be found to exist between the tropic of Cancer and the north pole. By this generalization, he would imagine twelve out of thirteen parts of the land of our temperate and arctic zones to be submerged. Such theorists should be reminded, that if the ocean was ever universal, its mean depth must have been inferior, and if so, the probability of deep water within the arctic circle is much lessened, and the likelihood of a preponderance of ice increased, and the heat of the ancient climate rendered more marvellous. To this objection, however, they will answer, that they do not profess to restrict themselves to existing analogies, and they may suppose the volume of water in the primeval ocean to have been greater. Besides, the high temperature, say they, was caused by heat which emanated from the interior of the new-born planet. In vain should we suggest to such reasoners, that when the ocean was in excess in high latitudes, the land in all probability predominated within the tropics, where, being exposed to the direct rays of the sun, it may have heated the winds and currents which flowed from lower to higher latitudes. In vain should we contend that a greater expanse of ocean, if general throughout the globe, would imply a comparative evenness of the superficial crust of the earth, and such an hypothesis would oblige us to conclude that the disturbances caused by subterranean movements in ancient times were inferior to those of later date. Will these arguments be met by the assumption, that earthquakes were feebler in the earlier ages, or wholly unknown,-as, according to Werner, there were no volcanos P Such a doctrine would be inconsistent with other popular prejudices respecting the e.xtraordinary violence of the operations of nature in the olden time; and it is probable, therefore, that refuge will be taken in the old dogma of Lazzoro Moro, who imagined that the bed of the first ocean was as regular as its surface, and if so, it may be contended that sufficient time did not elapse between the creation of the world and the origin of the car- K2 |