Chapter 7 



CONTOUR DIVING 



THE FOUR final bathysphere dives of 1930 were de- 

 voted to what I might describe as contour diving, 

 to steal part of an aviation term. This is decidedly 

 more risky than deep dives in the open sea, but is of equal 

 scientific importance. It opens up an entirely new field 

 of possibilities, the opportunity of tracing the change 

 from shallow- water fauna, corals, fish, etc., to those of 

 mid-water, with the hope finally of observing the disap- 

 pearance of the latter, and the change, gradual or abrupt, 

 into the benthic, or deep-sea, forms of life. We know ab- 

 solutely nothing of this at present, as the transition zone 

 is so rough and untrawlable that there is no method known 

 of learning anything about it. Nets are torn to shreds and 

 dredges catch almost at once, the wire breaks and not a 

 single organism comes up. 



I worked out the simplest method during the last dives 

 of 1930. I brought the Gladisfen and Ready as close to 

 shore as I dared on a day of perfect calm with a slight off- 

 shore wind and there began diving, with the bottom, nine 

 or ten fathoms down, actually in sight from the deck. 

 We were lowered to within two fathoms of the reefs 

 while the Ready drifted slowly seaward. As it turned out, 



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