THE BIRTH OF THE BATHYSPHERE 9 1 



outlined by Colonel Roosevelt, as representing our re- 

 spective preferences. We worked out many details but 

 never recurred to the subject again. 



During 1927 and 1928 I considered various plans for 

 deep-sea cylinders that would be strong enough to sink 

 deep into the ocean, but all of them, due to their flat 

 ends, proved impractical. With each 33 feet of depth the 

 pressure of sea- water increases one atmosphere (14.7 

 pounds to the square inch) , so at the depth of a half mile 

 the pressure is over half a ton to each square inch. Any 

 flat surface would be crushed in unless it were impossibly 

 thick or braced by an elaborate system of trusses. 



And so, since there is nothing like a ball for the even 

 distribution of pressure, the idea of a perfectly round 

 chamber took form and grew. By 1929 Mr. Otis Barton 

 had developed and actually had constructed a steel sphere, 

 large and strong enough to permit us to enter, to be 

 sealed up and keep ourselves alive, to descend into and 

 return safely from the depths of ocean. Mr. Barton de- 

 serves full credit for the contributions of time, thought, 

 and money which he devoted to this work, while Captain 

 John H. J. Butler designed and worked out the various 

 details of the sphere. I was able to bring to bear but a 

 small amount of helpful suggestion, but an unlimited 

 belief and faith and keenest interest in the scientific re- 

 sults of this venture. Never for a moment did any of us 

 admit the possibility of failure — Barton and his associates 

 were sustained by their thorough knowledge of the me- 



