its rubber g and its nut e and the small round piece of plexiglas A, but 

 it forms outside the wall of the cabin/a rather bulky head. In this head 

 are the ends of thirty-six 'Pyrotenax' cables of y in. external diameter. 

 Their cores k are soldered to thirty-six copper wires which, together 



Fig. 24. Passage of thirty-six thin electric cables through the cabin wall 



forming the cable /, pass through the plug to enter the cabin. The 

 thirty-six wires of this cable are insulated one from the other by 

 cotton and the whole cable is carefully coated with paraffin. The 

 plug is prolonged by a tube b closed by a plate a pierced with thirty- 

 seven holes. The base of the head is filled with Araldite D : above this 



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