THE BATHYSPHERE OF 1 93 4 24 I 



Two new oxygen valves of a type recently perfected by 

 the Air Reduction Company have been installed. These 

 valves will deliver oxygen accurately to within i per 

 cent of the gauge reading, and are also capable of showing 

 the exact amount of oxygen escaping regardless of pres- 

 sure. This is in direct contrast to the single valve used 

 before, in which the error of the gauge was considerable 

 and which might not deliver oxygen against pressure, even 

 though the gauge still showed it to be escaping. In the 

 new pieces of apparatus, the indicator is not a needle 

 against a dial, but a small, stainless steel ball within a cal- 

 ibrated glass tube. The amount of oxygen escaping deter- 

 mines the height of the ball in the tube, as the ball sits on 

 top of the escaping stream of oxygen. 



The release of oxygen in the bathysphere was reduced 

 in 1934 from 2 litres to i litre per minute for 2 divers. 



Barometer: A small recalibrated barometer is hung in- 

 side of the sphere as a check on too great a flow of oxygen. 

 Under any circumstances the increase in pressure is very 

 small. Even if both oxygen tanks were allowed to escape 

 into the sphere, only an additional three-fourths of an at- 

 mosphere would be present. 



Chemical Blower: During the 1930 and 1932 dives the 

 internal atmosphere was purified by having the air pass 

 over open trays of chemicals, impetus being given to the 

 air by periodically waving palm-leaf fans. This year it was 

 considered advisable to have a more positive means of keep- 



