482 NATURAL SCIENCE. ^^^^^,_ 



work which promises to hold the same relation to the schemes of 

 Elie de Beaumont that "the Origin of Species" held to the theories 

 of Oken and Lamarck. During the past two or three years, the 

 heresies of Suessism seem to have been steadily gaining ground, and 

 some measure of their present influence may be estimated from the 

 fact that they have formed the theme of two of the Presidential 

 Addresses at the recent meeting of the British Association at 

 Edinburgh. 



The *' New Geology," as Professor Lapworth has aptly named 

 it, may be defined as the application of the results of the old geology 

 to the discovery of the factors that have determined the remarkably 

 symmetrical arrangement which, often disguised by local and super- 

 ficial variations, rules in the existing physiography of the world. 

 Its scope may best, perhaps, be comprehended by a perusal of the 

 two addresses. 



The main interest in Professor James Geikie's discourse to the 

 Geographical Section on "Coast Lines" was, that he so clearly 

 stated the differences between what Professor Suess has called 

 Atlantic and Pacific types, the distribution of which has been figured 

 by Neumayr.' Professor Geikie showed, moreover, that the cause 

 of the difference was simply due to age : that round the great oceans, 

 the main north and south coast lines probably date from the same 

 primeval age, but that around the Pacific, and most typically on 

 the American margin, comparatively recent earth movements have 

 raised mighty mountain chains, now studded with volcanoes and 

 closely following the extreme verge of the continental plateaux. On 

 the Atlantic, on the other hand, the ranges upon the ocean border 

 are of an enormous age, and therefore have been denuded into low 

 rounded hills, are indented by gulf and fiord, and. have been cut far 

 back from the margin of the oceanic trough. In Professor Lapworth's 

 address, on the other hand, the fundamental identity of the structure 

 of oceans and continents was clearly demonstrated, the former being 

 the troughs that balance the elevations of the latter : in each 

 depression corresponds to depression, and ridge to ridge, and on both 

 alike the lines of volcanic action lie along the weakened limbs of the 

 great earth-fold. There is at first sight some apparent contradiction 

 between the two addresses, but as far as such actually exists it is 

 mainly on points of detail. At first it does seem as if the fact that the 

 dominant north and south lines were developed in primeval antiquity 

 were in favour of the permanence of the oceans and continents ; but 

 the mid-oceanic ridges probably date from the same time, and if 

 amid the numerous relative changes of level they had stood above 

 the ocean surface, and the existing continents had subsided, they 

 would have furnished quite as strong an argument for their having 

 been always continental, and existing land areas been always oceanic. 



' Erdgeschichtc, vol. i., p. 345. 



