THE REIGN OF FIRE. 



53 



highly heated portions. If the solid and the molten por- 

 tions suffered equal losses of heat, the molten, by shrink- 

 ing the most, became too small for the enveloping crust. 

 The crust, there- a 



fore, must wrin- ^ b\.. 



kle, to fit the 

 shrinking nucle- 

 us. Thus incip- 

 ient inequalities 

 of the surface be- 

 gan to appear. 

 These were the 

 germs of moun- 

 tains and of con- 

 tinents. From a 

 new-born wrinkle 

 grew the lofty 

 Cordillera. 



A scene of ter- 

 rific sublimity ap- 

 proaches. As yet 

 no water existed upon the earth. No rain had fallen upon 

 the parched and blackened crust. All the water which 

 now fills the oceans, and the rivers, and the lakes — all 

 which saturates the atmosphere, and the soil, and the 

 rocks — rested then upon the earth as an arid, elastic, in- 

 visible vapor, extending an unknown distance into sur- 

 rounding space. This vapor was not cloudlike, but in- 

 tensely hot and transparent. It was a gas, like the steam 

 just issuing from the escape-pipe of a steam-boiler. The 

 time had now arrived, however, when the remoter regions 

 to which this aqueous gas extended began to be so far re- 

 duced in temperature as to cause condensation to begin — 

 as the heated steam, rushing from the locomotive, soon 



Fig. 13. Ideal Section of the Earth in primeval times. 



a, a, a. The surface when solidification first commenced. 



b, b, b. Wrinkles developed in the crust by the shrink- 



age of the nucleus. 



