RAILWAY CONSTRUCTION. 241 



and the screw turned round and downwards by means of an iron 

 bar lever used as a spanner or wrench to the nut shown on the 

 sketch. The same tool is also serviceable for straightening rails 

 which have become crooked or kinked. Large and more com- 

 prehensive machines are used for bending rails in large quantities 

 or setting them to exact curvature, but, being heavy and 

 cumbersome, they are rarely taken away from the store-yards. 



Strong steel shovels of the form shown in Fig. 372 are the 

 most suitable for platelayers' general use when working with 

 gravel, sand, or broken stones. 



For driving iron spikes and wooden keys in cast-iron chairs 

 a long-handled hammer is the most convenient for work, and its 

 long swinging action produces considerable force without much 

 actual labour. 



Road-gauges, nut-wrenches, short straight-edges, spirit-levels, 

 ratchet-drills, augurs, and cold setts of well-tempered steel for 

 cutting rails, are all required by the men engaged in laying 

 permanent way. 



The following summaries give the estimated cost of materials 

 alone for one mile of steel bull-head rail and steel flange rail 

 permanent way of different weights. The 90-lb. steel bull- 

 head rail is at present the heaviest of that section laid down to 

 any extent on our home railways, and the chairs and fastenings 

 are made heavy to correspond to the rail and the traffic for 

 which it is intended. As the rails in the summaries become 

 lighter, the weights of the chairs and fastenings are decreased. 

 As yet there are not many samples of the 100-lb. steel flange 

 rail; but in those places where it has been laid down it has 

 been supported with a liberal supply of sleepers, to obtain 

 increased bearing surface. With a 5^-inch flange, and a 

 rectangular sleeper 10 inches wide, the bearing surface on the 

 wood is only about 55 square inches, as compared with about 

 100 square inches, the bearing surface of a large cast-iron chair 

 for a heavy bull-head rail. As previously explained, a small 

 bearing surface on a sleeper tends to the cutting down into the 

 wood, and rendering the sleeper unsafe and useless even before 

 it has become unserviceable from decay : hence the reason for 

 ample bearing surface on the sleeper. The last two summaries 

 refer to 3-foot narrow-gauge lines. In more than one instance 

 the 45 -Ib. rails first laid down have been found much too 

 light for the engines required to work the traffic, and when 



B 



