THE CONTINENT 



parallels the Scandinavian Shield. The Great Lakes 

 are like the Baltic Sea and Lakes. The Appalachian 

 Mountains resemble the Hercynian chain in Europe. 

 The great mountain arcs of the West Indies are akin 

 in time and shape to those surrounding the Mediter- 

 ranean Sea, etc., etc. These two continents are there- 

 fore closely allied. Perhaps we may compare the 

 southeast of Asia, with its huge plateau, block faults, 

 mountain arcs and festoon islands, with the western 

 portion of North America. 



Far different from these is the solid resistant block 

 of Africa, with barely a sign of late folding through- 

 out its vast extent. It lies perhaps at the other extreme 

 of continental *'build." Australia and South America 

 form another pair, somewhat symmetrical about the 

 Pacific Ocean. Thus the great Brazilian Shield may be 

 equated with the Western Shield in Australia. The 

 long geosyncline (down-warp) from Adelaide north 

 to the Gulf of Carpenteria resembles the lowland belt 

 from Buenos Ayres to the Orinoco ; the humble East- 

 ern Highlands of Australia with their drowned neigh- 

 bors to the east are due to crustal ripples probably 

 moving outward from the Pacific, just as are the giant 

 ranges of the Andean Cordillera. We can perhaps 

 show this secondary symmetrical aspect of the w^orld 

 plan in tabular form. (See Figure lo.) 



I have ventured to insert Antarctica in the above 

 table as a continent more akin to Africa than any of 

 the other continents, and like it, to some extent, lying 

 between, though to the south of, associated pairs of 

 enantiomorphs. Just as we find Africa characterized 



87 



