ASYMMETRY OF THE NORTPIERN HEMISPHERE 105 



The farther consideration of this question may be held in reserve until 

 the southern hemisphere can be brought into consideration. This much 

 is already clearly recognizable : That the contrast between the structure 

 of the northern part of America and of eastern Asia betrays a lateral 

 asymmetry of this hemisphere reaching back into the Cambrian time. 

 We should not say an original asymmetry, for the Laurentian rocks were 

 also folded, and that in pre-Cambrian time. The direction of these folds 

 seems to have been a wholly independent one, but their strike is known 

 in only a relatively small part of the broad region. 



One is inclined to suspect that the formation of the curved chains in 

 Asia, open toward the north, stands in some connection or other with the 

 outflow of superfluous earth-mass from the pole — that is, with a flatten- 

 ing of the same. One can also recognize a certain resemblance between 

 these curved chains and the course of the moraines, and also the forms 

 of the glacier lobes which Chamberlin draws across the east of the 

 United States. We shall have at a "later time to investigate whether 

 curved chains directed toward the north are present in the southern 

 hemisphere, but already the influence of the Laurentian mass (with 

 Greenland and a portion of the polar land) appears plainly enough. 



More striking than any connection with the pole of rotation appears 

 a certain relation to the magnetic pole which lies in the midst of the zone 

 of inflow. In fact, the distribution of the guiding lines (Leitlinien = axial 

 lines of the mountain chains) seems to favor a connection between the 

 mountain-forming force and terrestrial magnetism, as suspected by Edm. 

 Naumann and other investigators, and that in the sense that the latter 

 is the result of the former, a result influenced also by other causes. 



It now appears also that the separation of the movements into tangen- 

 tial (folding) and vertical (sinking) motions must be much more sharply 

 held than before. The relation of the Atlantic ocean, which is younger 

 than those chains, to these latter makes this clear. The acute compar- 

 ison drawn a long time ago, especially by Reyer, between mountain 

 folding and fluid motion was justly objected to because a fall for such a 

 fluid motion was not recognizable. As soon as we are able to oversee 

 the whole hemisphere and distinguish a region of outflow and one of 

 inflow, this question also gains a new importance. 



In relation to the often-discussed question of the permanence of the 

 continents and the oceans, we recognize the following : individual folded 

 chains are dislocated and broken up in horsts, and later folds heap them- 

 selves up against the horsts. At the same time the location of the region 

 of outflow and the region of inflow, as well as the arrangement of the 

 superficial tensions which find expression in the guide lines of the folds, 



