Appendix ^ 



Passage of the Electric Cables and Tubes through the Cabin Wall 



The passages of a great number of electric cables, high-pressure 

 tubes and two ventilation conduits (schnorkel) presented an interesting 

 series of design problems. All these passages had to meet two con- 

 ditions : to be watertight and strong. 



Around the porthole, in the place where the thickness of the cabin 

 wall is 5-9 in., we bored twelve holes of identical dimensions. On the 

 external side each hole, for a length of i -97 in., had a diameter of i -97 

 in. Then came a cone of an angle of 45° for a length of -55 in., which 

 brought the diameter down to -79 in. From a depth of 2-52 in. 

 onwards the hole continued towards the interior of the cabin with a 

 diameter of -79 in. 



Watertightness is achieved in all the holes in the conical part by 

 means of a conical ferrule of plexiglas, forced into its seating by a steel 

 plug. This construction is analogous to that of the portholes. 



THE PASSAGE OF THE SCHNORKEL 



To have effective ventilation, it is necessary to conserve as much as 

 possible the free section that is offered in the hole of -79 in. diameter. 

 From the interior of the cabin one must be able easily and rapidly to 

 open or close the passage. 



Fig. 22 illustrates the design chosen by us. At the outside of the 

 hole a thin metal box (visible at the top of Plate XIV), which will 

 never have to resist high pressures, is screwed down on the orifice. 

 The reliability of the joint between this box and the cabin dis ensured 

 by means of a rubber washer. To this box is connected a long tube 

 which traverses the float and ends on the deck. The tops of these 

 tubes (folded back towards the base) are quite visible in Plates XI and 

 XXI. A thin iron rod j passes through the entire length of the tube e. 

 From the outside, it is fixed to an iron plug g. If, by means of screws 

 placed inside the cabin, one pulls upon the rod, the plug forces the 

 plexiglas ferrule into its seating. The watertightness thus effected is 

 suflicient for low water pressures. As soon as the bathyscaphe dives, 

 the external pressure of the water is added to the pull of the rod. The 

 plexiglas is then compressed more and more between its seating and the 



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