PRE-HURONIAN LAND CONDITIONS 189 



tocene. Sederholm's Bothnian slates with seasonal banding, probably of 

 somewhat the same age, show similar conditions in Finland. 



Land can be discovered still farther down in the misty depths of time, 

 for the pebbles of the Seine and Dore conglomerates include far older 

 sedimentary rocks derived from the Keewatin or Couchiching or Gren- 

 ville Series, showing vast destruction of land surfaces in pre-Laurentian 

 ages at the very beginning of the geological record. 



These glimpes of American land surfaces in a past twice removed from 

 the ancient pre-Huronian continent give one a strange vista into a dim 

 antiquity almost infinitely remote from a dweller in the post-Pleistocene. 

 There is no visible beginning to dry land on the continent of America. 



Why should there be Dry Land ? 



Though it is commonly accepted that there were lands in the earliest 

 known times, there are geologists who hold a theory of the origin of the 

 world which logically excludes the possibility of land showing itself above 

 the sea. The original nebular hypothesis, if followed without mishap 

 from the stage of a cooling gas to that of a liquid, and then of a solid, 

 would result in a correct spheroid of rotation. The lithosphere thus 

 formed Avould be covered by an unbroken hydrosphere, followed in its 

 turn by an atmosphere. A good workman would certainly have come 

 close enough to the ideal form of his world to prevent errors amounting 

 to G0,000 feet. A properly manufactured world, following the orthodox 

 nebular process, would be completely covered by an ocean 8,000 or 10,000 

 feet deep. 



This ideal world without a continent or an island would have avoided 

 many difficulties. Land animals, blundering, bloodthirsty, even cannibal 

 in their crude instincts, could never have existed. The ocean itself might 

 never have been inhabited if life originated, as is commonly supposed, 

 under shallow- water conditions. How quiet and peaceable such a world 

 would have been ! One almost longs for it under the turmoil of present 

 conditions. 



A world without land would have had its disadvantages, however. 

 There could have been no geologists and no geology. 



But it is idle to speculate as to the possibilities of a landless world. 

 The blunder was committed and the lithosphere was so far warped out of 

 shape that more than a quarter of it rises above the sea. One might in- 

 quire, however, whether the blunder might not have been rectified by pro- 

 viding more water, so as to drown out the objectionable lands. We know 

 that there have been times when much of the present continental area was 

 encroached on by the sea. Was there more water then, or was it merely 



