WIRE ROPE TESTS. 253 



The combination of mechanical friction with the direct 

 pull against the white metal makes a sound job, but an 

 equally satisfactory attachment can be made with the white 

 metal alone. This may be done by fraying out the 

 ends of the rope, having previously bound the rope with 

 wire to prevent the wires from becoming loose. The 

 ends of the wires are bent over for about 1 in. of 

 their length, the whole forming a conical bunch. This 

 can then be placed in the socket, which should have a small 

 taper, and be as long as possible. Before being placed in the 

 socket the wires should have been cleaned in acid and the 

 inner hemp core (if any) cut out. The whole may then be 

 poured full of some fairly hard white metal. This holder 

 (Fig. 123), as used by Professor Goodman, of the Yorkshire 

 College, rarely fails to hold the rope securely, and the rope 

 most frequently breaks in the body somewhere between 

 the two holders'. A great desideratum in wire rope 

 is that there shall be a uniform tension on all 

 wires which go. to make up the rope. This end is 

 probably more certainly attained with a fastening in which 

 the wires are surrounded by a solid mass of metal than 

 where friction is depended upon. 



In this connection Johnson* recommends that after the 

 ends of the rope have been boiled in caustic soda, and 

 thoroughly washed in hot water, they should be dipped in 

 chloride of zinc and then in molten solder, so that the 

 wires are tinned. The alloy recommended is one consisting 

 of tin, lead, and antimony. Tejmager makes use of an 

 alloy of eight parts tin, one part copper, and one part 

 antimony for iron and mild steel wires ; and nine parts 

 lead, two parts antimony, and one part bismuth for nard 

 steel wires. Pierre Arnould-f* used for his alloy equal 

 parts of lead and zinc. 



Rouleaux]: recommends, among odier means for hold- 

 ing the ends of a wire rope, a socket in which the rope is 

 unravelled, the wires turned inwards, and molten metal 

 poured in. This socket is indicated on Fig. 124. From 

 what the writer has seen of the tests of various holding 

 devices, he is led to believe that of the holding sockets 

 based on the wedge principle very few indeed are as strong 



* " Materials of Construction," page 694 ; also see Engineering, 

 September llth, 1896. 



t Proceedings of the Institution of Civil Engineers, vol. xcviii., 

 p. 412. 



J ' Constructor," p. 182. 



