14 



JUNGLE ISLAND 



century. No one can guess how long it will keep 

 on rising. It is just as likely that some day it 

 will begin to sink once more. 



Fig. 4. The spillway of the Gatun Dam 



The engineers who had made the Canal worked 

 much faster than the earth forces which had for 

 millions of years lifted and lowered the land in 

 their own way. The men had dams and a swift 



