160 LIGHT SCIENCE FOR LEISURE HOURS. 



DEEP-SEA DREDGINGS. 



have ever been strangely charmed by the 

 unknown and the seemingly inaccessible. The as- 

 tronomer exhibits the influence of this charm as he 

 constructs larger and larger telescopes, that he may 

 penetrate more and more deeply beyond the veil which 

 conceals the greater part of the universe from the 

 unaided eye. The geologist seeking to piece together 

 the fragmentary records of the past which the earth's 

 surface presents to him, is equally influenced by the 

 charm of mystery and difficulty. And the microsco- 

 pist who tries to force from Nature the secret of the infi- 

 nitely little, is led on by the same strange desire to 

 discover just those matters which Nature has been most 

 careful to conceal from us. 



The energy with which in recent times men have 

 sought to master the problem of deep-sea sounding 

 and deep-sea dredging is, perhaps, one of the most 

 striking instances ever afforded of the charm which the 

 unknown possesses for mankind. Not long ago, one of 

 the most eminent geographers of the sea spoke regret- 

 fully about the small knowledge men have obtained of 

 the depths of ocean. " Greater difficulties," he re- 

 marked, " than any presented by the problem of deep- 

 sea research have been overcome in other branches of 

 physical inquiry. Astronomers have measured the 



