bodies. If one places a small piece of this wax in a glass filled with water 

 at ordinary temperature, at the end of a few hours it sticks by itself to 

 the bottom of the glass. In fact we never observed any cracks in the 

 Araldite. But if any had occurred, the wax would have completely 

 blocked them. 



This sort of passage for conduits has a great advantage : we were 

 able to put through the wall conductors with a core having a diameter 

 of '394 in. The current of the large battery could therefore be brought 

 directly to the cabin: and the current operating engines and flood- 

 lamps could also, by means of cables containing three large cores, 

 pass through the wall. Thus we could completely give up all the 

 relays, used in the FNRS 2 and also the FNRS j. The elimination of 

 these relays, which must be protected by oil against the sea water, 

 constitutes an enormous simplification. 



THE PASSAGE OF HIGH-PRESSURE TUBES AND OF THE RADIO 

 AERIAL 



We have already mentioned the two steel tubes, by means of one of 

 which the pressure gauges are connected to the external pressure, 

 while the other serves to conduct compressed air into the antechamber 

 to expel the water. These tubes have an external diameter of -25 in. 

 The aerial of our radio is connected with our radio by a *Pyrotenax' 

 cable of -197 in. external diameter. These three cables pass through 

 the same hole in the cabin. The construction is analogous to the 

 preceding one, except in two points : we have been able to do without 

 the plate h ; and the cone c is pierced with three holes. 



THE PASSAGE OF 36 THIN ELECTRIC CABLES 



A large number of cables of small section must be provided for to 

 be connected with various instruments placed outside the cabin. From 

 the beginning we had to have six wires for the three electro-magnets 

 (two to carry the ballast tubs and one to hold the trail-rope), four for 

 the two magnetic ballast valves, three for the telephone (only used on 

 the surface), two for the small lights and one for tne tachometer. 

 That is sixteen wires. But we also wanted to reserve for ourselves the 

 possibility of connecting up other instruments later on. In the end, not 

 to be caught napping, we had thirty-six copper wires of 2-5 in. diameter 

 passed through a single hole in the cabin. Fig. 24 shows the con- 

 struction adopted. We see again the same steel plug c with its screws </, 



[174] 



