green's hypothesis 67 



southward and massed around the north pole. Between would be the 

 three oceanic depressions gathered around the south pole, contracting 

 northward. At the ends of the axis of rotation would be the Antarctic 

 continent, the fourth protuberance below, and the Arctic ocean, the 

 fourth depression above (see plate 9, figures 1 and 2). 



Shifting of the southern hemispheres. — Because the great masses in the 

 northern hemisphere were raised above their normal level, they would 

 lag to westward ; because the great masses of the southern hemisphere 

 were depressed below the normal level, they would be accelerated east- 

 wardly. This explained the position of South America east of North 

 America and Australia east of Asia. Indeed, in his view, the great mass 

 of Asia caused it to lag behind so much that it was thrust against and 

 joined with Europe. 



The twinning plane. — These opposing forces produced a shearing of the 

 northern hemisphere on the southern, along a plane passing through the 

 three intercontinental seas, a plane placed 12 degrees nearer the north 

 pole because of the excess of the northern masses, and in the plane of 

 the ecliptic instead of the equator, because the shearing force, although 

 acting in the plane of the equator, found in the ecliptic a plane of weak- 

 ness caused by the strain of the internal tides. This plane passing 

 through — indeed causing — the three mediterranean seas he called, some- 

 what fancifully, the twinning plane, and conceived the southern hemi- 

 sphere to have been rotated about 30 degrees to the right like a twin 

 crystal to bring the southern continents into their present positions. 



Without accepting them, I have discussed his explanations of these 

 two points below (see pages 75-78) in order to consider the value of the 

 inertia force and the tidal stresses which he employs in this portion of 

 his hypothesis. 



ARGUMENT IN FAVOR OF TETRAHEDROID TENDENCY IN FORMATION OF 



EARTH'S CRUST 



In advancing arguments for his theory, Green cites experiments where 

 hollow tubes uniformly collapse under atmospheric pressure into three- 

 sided forms with rounded edges and concave sides, like a horizontal sec- 

 tion of the earth in the southern hemisphere, and claims to have seen a 

 distinctly tetrahedral shape in soap bubbles and. bubbles in water, and 

 he cites many cases where astronomers have observed a four-shouldered 

 form in the larger planets. 



The hypothesis connects the main facts relating to the earth's grand 

 feature lines by a very simple principle. It would postulate a certain 

 evolution of the continents and oceans, and may, indeed, be taken as 

 furnishing an a priori ground for this postulate. It is a hypothesis of 



