THE IMPENETRABLE SEA 



own by billions of miles long before (only five hundred 

 years ago) explorers began voyages across unknown seas. 

 Even then the depths of the oceans remained unexplored, 

 and it was less than a century ago that science looked 

 down into the world's waters and, as oceanic research 

 really began, saw within them points of light which now 

 seem to challenge the known stars in number and fas- 

 cinating interest. 



As we begin to realize the stupendous significance of 

 the fact that the world's oceans are not entirely dark, but 

 are populated, from the sea-floors of the great deeps up- 

 wards for miles, with countless millions of creatures 

 carrying their own lamps, rivalling the known stars in 

 number and far exceeding the lighting devices of the 

 world's land surfaces in diversity and ingenuity, our con- 

 ception of the oceans must necessarily change. They will 

 become vast areas of increasing illumination ; physically, 

 as more and more living species are catalogued by natural 

 historians, and imaginatively as oceanographic research 

 widens and deepens within them. 



The success of undersea exploration will largely de- 

 pend upon man's use of increasingly efficient lighting 

 devices. 



In a physical sense, and also (within limits) in im- 

 aginative senses, the sea is becoming more and more 

 penetrable. Down into hitherto unknown depths, where 

 myriads of points and patches of light move in all direc- 

 tions through millions of cubic miles of dark water, man 

 is taking his own light-producers and his own appliances 

 to record scenes which have been registered only upon 

 the optic retinas of fishes for eons of time. 



The latest underwater lamp is one which has been 

 developed by the General Electric Co., Ltd., in colla- 

 boration with the Admiralty Research Laboratory. The 

 three main requirements of underwater lamps are : that 

 they must be light, easy to handle, and simple to operate. 

 The A.R.L.'s experiments have shown that these require- 



268 



