246 CHARLES R. KEYES 



The polar axis of the earth is regarded by Owen as extend- 

 ing from the center of one rhombic face to the center of the 

 opposite one. The sharp, four-sided axial angles of the 

 dodecahedron are near the Aleutian Islands, New Zealand, 

 and, on the earth's equator, at Sumatra and Quito ; while the 

 remaining two lie in the Alps and south of the Cape of Good 

 Hope. Thus oriented the following propositions are formu- 

 lated : 



1. Centers of rhombs are usually occupied by water or low 

 land ; 



2. Ridges of rhombs usually give rise to mountains, and river 

 sources ; also sometimes to parallel valleys with important 

 rivers ; 



3. Many of the apices are characterized by vicinity of vol- 

 canic groups ; 



4. Rhombs facing each other have considerable similarity in 

 the distribution of land and water; 



5. Daily rotation and annual revolution seem to have deter- 

 mined the configuration of land. 



How closely these generalizations accord with facts may be 

 easily tested by reference to any school globe. Why Owen 

 should have oriented the dodecahedron just as he did does not 

 appear. It would seem that in all cases of this kind the starting 

 point which is first selected has much to do with subsequent 

 developments. In Owen's case the depression of the Arctic Ocean 

 offered the schematic rhomb. Then, too, the Mediterranean 

 area required special attention. So important is the last named 

 region that Michel-Levy, in his plan, was led to make it a point 

 where three polar edges of his tetrahedron should meet. 



If there be anything in the idea of a collapsing crust on a 

 shrinking interior, the tendency of the surface toward the assump- 

 tion of any angular form would find adequate reason in an adjust- 

 ment which would produce as nearly as possible the least amount 

 of deformation in the lithosphere compared with the amount of 

 change in the bulk of the earth. This geometrical shape is, as 

 already noted, the tetrahedron ; but a four-sided figure in which 



