56 The Bible of Nature 



envelope, the bulk of which gave rise to the 

 moon. 



Soon after the birth of the moon the earth be- 

 came consolidated (with a surface temperature of 

 about 1170° C.) and the moon may have been in- 

 fluential in determining high-pressure areas and 

 low-pressure areas over the surface of the crust, 

 which may have had something to do with prim- 

 itive depressions and elevations. This, as Pro- 

 fessor Sollas says, was the second critical period 

 in the history of the earth, the stage of the "con- 

 sistentior status." It may have been forty mil- 

 lions of years ago, or much more. 



When, with continued cooling, the temperature 

 of the surface fell to 370° C, the steam in the at- 

 mosphere would begin to liquefy, and this was 

 the first step in the origin of the oceans. The hot 

 waters began to be localized in primitive faint de- 

 pressions, and, acting energetically on the silicates 

 of the primitive crust, began to be salt. In a man- 

 ner difficult to understand a distinction was es- 

 tablished between ocean basins and continental 

 areas. 



Through stages more or less like those hinted 

 at above the earth has reached its present state. 

 The vast nucleus or "centrosphere" seems to be 

 practically solid, the melting point of the metals 

 and metalloids being raised by the immense 

 pressure. Outside the central mass there is "a 



