1889]. THE DISPLACEMENT OF BEACH-LINES. 31 



as are situated in the higher latitudes. The regions named are 

 (cfr. Lapparent) upheaved more than the surroundings, which 

 also quite coincides with the views discussed above. But in 

 lower latitudes, where a general sinking takes place in the course 

 of time, the portions left undisturbed will form real „Horste M of 

 Suess's kind. And it is scarcely opposed to our hypothesis if 

 we suppose, with Sttess, that the Indian Ocean is formed by a 

 sinking, and that Africa, Madagascar, Hindostan and several 

 other lands are „Horste", parts of the crust which have been 

 left undisturbed, or which have sunk less than their surroundings. 

 In these countries there appears, so far as their geology is yet 

 known, to be only few marine formations belonging to the mesozoic 

 and cainozoic eras. 



I have said, above, that the different parts of the crust must 

 be assumed to have different powers of resistance to the internal 

 strain. We may conclude that, from the unevenness of the sur- 

 face, and also from ancient, originally level, formations having 

 been upheaved with great irregularity at different places. In 

 other words, we have an unevenness of surface which cannot be 

 accounted for only by the action of the erosive forces. 



The alterations in the surface of the Earth really take 

 place in very different degree at different places. The greatest 

 disturbances are to be found in the folded mountain ranges, and 

 these we have belonging to all geological periods. It is worthy 

 of notice that places where great folding took place in ancient 

 times, appear, later, to have been left undisturbed by the folding 

 process 1 ; because above the abraded tops of old folds there lie, often, 

 even old formations in undisturbed level position. The loftiest 

 folded ranges of the Earth are, therefore, those where the folding 

 has continued up to the latest times. 2 Along both coasts of the 



