THE BIRTH OF OUR WORLD 13 



as though the present disposition of the continents and seas 

 confirms this calculation : 1 the North Pole is occupied by a 

 sea covering the base of the pyramid ; at the South Pole a 

 continent indicates the apex opposite the base ; the Eurafrician 

 continent represents one of the lateral levellings ; the two 

 Americas correspond to the second, and the Australasian 

 continent separated from Europe by the Aralo-Caspian 

 depression (the bed of an ancient sea) represents the third. 

 These three continental masses widen towards the north, and 

 duly become narrower towards the south. And, further, 

 while the earth revolves on its axis, each of its meridians 

 revolves in a given period, through an equal angle. 

 But in order to revolve through an equal angle the points 

 nearest the equator have to traverse an arc much greater than 

 those near the poles, and they therefore move much more 

 rapidly in a tangential direction. If, however, one part of this 

 meridian sinks, the sunken points will move faster than they 

 should, and will be in advance of the projecting points with their 

 markedly retarded movement. The continents would thus 

 have to twist their apices toward the east ; and this torsion, 

 evident as regards America, would lead to a rupture in the 

 central portions. This would explain the existence of the 

 Mediterranean and Caribbean Seas ; and also the separation 

 of the Australian continent from Asia. All this, unfortunately, 

 must necessarily have taken place not in our days, but at the 

 very beginning of the contraction of the earth's crust. It is 

 always possible that the initial arrangement of the continents 

 and seas began by conforming to this irreproachable calculation; 

 but since then other causes have supervened which have 

 modified the course of events. The oldest geographies extant 

 yield no trace of tetrahedral arrangement, and the present 

 disposition of land and water, which seems to conform to the 

 calculation, is of relatively recent date. This conformity is a 

 sort of anachronism. We have therefore had to abandon with 

 regret, and only after many efforts to save it, that mathematical 

 explanation, so seductive at first sight, known as the tetra- 

 hedral theory. The contours of the continents, their extent, 

 and their altitude have changed many times. Areas long 

 continuous have been cut up into many smaller ones ; isolated 



1 V, 55, 1245. 



