Before describing the sphere's systems in detail, it 

 is desirable to indicate the interior layout. The inside of 

 the sphere is divided into six bays. Bay No. 1 includes 

 the entrance to the sphere, the hatch, and the seat for the 

 scientific observer. Bay No. 2 houses instrumentation, 

 some power supplies, and the underwater telephone. 

 Bay No. 3 is the pilot's operating panel with most of the 

 controls and instruments necessary for operation. Bay 

 No. 4 contains the primary observation window, the 

 camera mounts, the manometer pressure gauge system, 

 and the air revitalization system. Bay No. 5 contains, in 

 one half, operational controls such as lighting circuits and 

 Fathometer and, in the other half, scientific instrumenta- 

 tion. Bay No. 6 is entirely free for scientific instrumenta- 

 tion. 



The bathyscaph is actually equipped with two spheres: 

 (1) the original or Terni sphere which was part of the craft 

 as originally delivered, and (2) the Krupp sphere which 

 was purchased a few months after the craft had been re- 

 ceived in the United States. The Terni sphere can withstand 



Sphere, exterior view 



13 



