12 THE STORY OP THE EARTH AND MAN. 



from the atmosphere, at first sending it all hissing and 

 steaming back, but at length allowing it to remain 

 a universal boiling ocean. Then began the reign of 

 the waters, and the dominion of fire was confined to 

 the abysses within the solid crust. Under the prime- 

 val ocean were formed the first stratified rocks, from 

 the substances precipitated from its waters, which 

 must have been loaded with solid matter. We must 

 not imagine this primeval ocean like our own blue 

 sea, clear and transparent, but filled with earthy and 

 saline matters, thick and turbid, until these were per- 

 mitted to settle to the bottom and form the first 

 sediments. The severu! changes above referred to are 

 represented in diagrammatic form in figs. 1 to 4. 



In the meantime all is not at rest in the interior of 

 the new-formed earth. Under the crust vast oceans 

 of molten rock may still remain, but a solid interior 

 nucleus is being crystallised in the centre, and the 

 whole interior globe is gradually shrinking. At 

 length this process advances so far that the exterior 

 crust, like a sheet of ice from below which the water 

 has subsided, is left unsupported; and with terrible 

 earthquake-throes it sinks downward, wrinkling up 

 into huge folds, between which are vast sunken areas 

 into which the waters subside, while from the inter- 

 vening ridges the earth's pent-up fires belch forth 

 ashes and molten rocks. (Fig. 5.) So arose the first 

 dry laud : 



" The mountains huge appear 

 Emergent, and their b"ead bare backs upheave 



