E. W. CLAYPOLE — CONTINENTS AND DEEP SEAS. 11 



the whole land planed down to a level it would be covered with water to the depth of 

 at least a mile. 



(a) One of the arguments advanced in support of the doctrine of permanence is that 

 no example of elevation sufficient in amount and extent to convert an ocean-abyss into 

 land or of depression sufficient to change a continent into a deep ocean can be brought 

 forward. 



It is quite true that most of the recent changes that geology has revealed are not 

 excessively great in amount. Some of them, however, reach high figures. It is gen- 

 erally admitted that during the later Pliocene period a land communication existed 

 from Scotland through Faroe and Iceland to Greenland, and perhaps to North America. 

 Such a communication implies the upheaval of the bed of the north Atlantic to the 

 amount of 350 fathoms over a long distance, and to double that amount over the deep 

 trough lying between Faroe and Iceland. A change of level of 3,500 feet almost 

 within the human era is scarcely an argument for great stability. 



But without lingering over intermediate dates, let us review the Tertiary period as a 

 whole and see what it tells us of subsidence and elevation. During the Eocene and 

 Miocene ages a vast mediterranean sea extended over southern-central Europe into 

 Africa and southern-central and eastern Asia. In it were deposited the great num- 

 mulitic and other limestones, reaching a thickness of 15,000 or 20,000 feet. At that 

 time, therefore, this area was one of subsidence to at least the extent of 2,500 fathoms, 

 or the depth of the present Atlantic. 



Yet this sea completely disappeared from geography during the Pliocene era, and 

 but for its deposits its very existence would be unknown. Its whole area has been 

 lifted above sea-level, and in some places, owing in part to corrugation, the Numinu- 

 lites may be collected at the height of 10,000 feet in the Alps and at 16,500 feet in 

 Thibet, indicating a change of level of 4,000 fathoms, equal to the profoundest depth 

 of the existing oceans. 



Nor is this a solitary or a specially strong case. On the northern slype of the Hima- 

 layas was deposited an almost continuous series of strata, ranging from the Silurian 

 to the Cretaceous. Disturbance followed, and on the disturbed beds the nummulitic 

 limestones already mentioned were laid down. The inference is Icijitimate that this 

 part of central Asia was a marine area during most of the time from the Silurian to 

 the Eocene. Yet on this very area now stands the loftiest country in the globe 

 (Thibet), a high, bleak plateau, measuring about 1,500 miles by 350 and covering 

 half a million of square miles, the average elevation of which is about 15,000 feet 

 above the sea. Neglecting the depth of the sea from which it emerged, here is evi- 

 dence of the elevation of a large area to an amount equalling all but the deepest parts 

 of the Atlantic 



Passing over for the present the arguments that may be drawn from the European 

 chalk, let us consider the American Cretaceous strata. In some places these reach a 

 thickness of 10,000 feet and on them lie 4,000 or 5,000 feet of Tertiary beds, indicat- 

 ing a subsidence of the basin in which they lie to the extent of 2,500 fathoms. Yet 

 much of this depression has been recovered, and now Cretaceous rocks are found at a 

 height of at least 4,000 feet in California and even higher in some parts of the Rocky 

 Mountains. 



But we may take a glance yet farther back in time: During the Mesozolc era a 

 great depression took place over an area including the sites of London and Paris, 

 which bears the name of the Anglo-Parisian basin, and in it the whole series of Meso- 

 zoic rocks was deposited, exceeding, according to D'Orbigny, 15,000 feet in thickness. 



