CREATION BY EVOLUTION 



ing up of the continental blocks and a sinking of the sea- 

 levels, and a new pulse beat of the earth takes place. 



When the continents are extensive and high the climates 

 are zonal — that is, there are zones of different climates in 

 different regions. The climate is cold at the poles, warm at 

 the equator, arid in central regions, and moist along the 

 coasts. When the continents are contracted and worn down 

 low the climate is non-zonal and equable, the conditions of 

 life are easy, and evolution is relatively slow. The rocky 

 strata of the earth's crust show clearly that there have been 

 several great continental pulse beats. A section of the walls 

 of the Grand Canyon, for example, affords an opportunity 

 to read the book of geology at a place where the earth has 

 herself turned back the pages. To one who has learned to 

 read the language in which it is written, nothing could be 

 more certain than the story thus revealed. It is a true story, 

 unspoiled and unedited by the hand of man. Those who 

 have become experts in reading the record of the rocks agree 

 in the interpretation of its pages, at least as to its main plot. 

 About some minor details different versions are offered. It 

 is clear, however, that since the earth reached its present 

 diameter, at least a billion years ago, there have been no less 

 than half a dozen major pulse beats of the earth ; and numer- 

 ous minor rhythmic changes have been superimposed upon 

 the major rhythm. It is also certain, as shown by fossils, 

 that the earth has been the abode of life during numerous 

 physical and climatic changes of far-reaching extent and of 

 great severity. 



Leaving now the exceedingly large units of the universe, 

 let us put on our shrinking caps and magically pass to the 

 exceedingly small world of the atom. Modern physicists 

 have revealed to us that the atom, once thought to be the 

 smallest thing in existence, is really much like a miniature 



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