FIRE, ROCK, AND SEA 37 



discoveries on the surface is now being revived on the ocean 

 floor, with all the new equipment that modern technical 

 development is making possible. 



We have seen how the great earth movements molded the 

 rocky confines of the River, at least as far as it has been re- 

 vealed by probing into its depths and into its past with man- 

 made instruments. With this part of our frame in place we 

 shall piece out in our next chapter the story of the stream of 

 evolution which has moved along with it in time, and which 

 links the geological past with the web of life within and 

 around the ocean today. 



