80-t 



Popular Science Monthly 



compartments are completely filled. In 

 this way the great pressure of the water on 

 lop of the hatches is relie\ed. 



In an emergency, the crew immediately 

 put on light di\ing-suils. These contain 

 oxygen apparatus which not only prevent 

 suffocation, but also prevent the water from 

 crushing the body. Three or four men 

 enter each compartment and shut the 

 water-tight door behind them. Letting in 

 the water, they open the hatch and climb 

 out. After they ha\'e 

 emerged, the hatch is 

 closed by gears con- 

 nected to it in the 

 inside of the sub- 

 marine. The water in 

 the compartment is 

 then ejected into the 

 ocean through drain- 

 pipes connected with a 

 h^'draulic hand-pump 

 which the imprisoned 

 men operate. Then 

 three or four more 

 of them may enter 

 the compartment and 

 escape in the same 

 way. 



After all the crew 

 reach the top of 

 the boat they 

 release a buoy which 

 nio\-cs upward towards 

 the surface cable with 

 it. Up this the men 

 nnist climb. 



It seems strange 

 that they must climb 

 out and are not forced 

 Ujnvartls as .soon as 

 they touch the water. 

 The reason for this is 

 that the weight of the 

 suits is so great that, 

 peculiarly enough, it 

 tends to keep the men 

 at \vhale\er level the\- 

 happen to be. 



Due to (he fact that 

 (he men have to ex- 

 pose themseKes to the 

 |)ressiire of the water, 



this plan cannot be used at a greater depth 

 than .?25 feet. Kven at this depth, the 

 l)ressure is H'.j tons pers(iuare fool. Divers 

 have gone down this far; but one, who went 

 down 28S feet, at the time of the F-4 

 disaster, permanently injured his linigs. 



In an cmcrnincy in lliis Mibin.uiiu-. tla- 

 crew put on liRlit ilivini; j.ncki'Is. escape 

 to tlie top of the boat tlirouRli the com- 

 partments and hatches, and climb to the 

 surface on the cable attached to a buoy 



which are 

 the hose. 



The manner in which the oxygen is 

 supplied from these suits is extremely 

 interesting. A small cylinder strapped to 

 the back of the wearer contains the oxygen, 

 which is stored at an enormous pressure of 

 one hundred and fifty tons per square foot. 

 The oxygen is slowly released from this by 

 an automatic ejector which regulates its 

 pressure as it is supplied to the body so 

 that it nearly equals that caused by the 

 ocean outside. After the ox>gen has been 

 consumed, it is thrown 

 oft by the lungs as 

 carbon dioxide, and 

 this the lungs force 

 into a cartridge of 

 chemicals where it is 

 completeh' absorbed. 

 Alter this absorption, 

 only the nitrogen of 

 the air remains, but 

 this is again passed 

 o\er the ejector and 

 mixed with fresh oxy- 

 gen before it enters 

 the lungs once more. 

 In this way the same 

 nitrogen is used over 

 and o\er again. 



In a third class of 

 devices, the men do 

 not leave the sub- 

 marine at all. Two 

 buo\s arc fitted in the 

 superstructure at 

 both ends of the sub- 

 marine. Attached to 

 each are a cable and 

 two flexible hose, 

 while directly under 

 the ]ioint where each 

 buo>- is held on the 

 submarine is a com- 

 partment into which 

 the crew get in time 

 of danger. Then the 

 lnio\s are released. 

 .\s the\- rise, the\' carry 

 liu' cables and hose 

 with them. An un- 

 limited amount of 

 fresh air can now be 

 had by working air- 

 connected to the lower 



pmnp: 

 ends < 



In the two compartments, the men must 

 stay imprisoned until a saU'age vessel 

 answers their <listress signals, given out by 

 an electrical llashlight within the buoys. 



