in some exceptional cases to 180 yards. At such distances as these, it is obviously of great importance to have a strong and thoroughly trustworthy means of connection between the points and the cabin, and for this purpose ordinary iron gas-piping was formerly used, but latterly it has been found that a steel channel section of rodding is far superior for the purpose, and the success attending this innovation has led to its adoption by several other railway companies. The chief advantage over gas-piping is that rods weakened by corrosion are readily detected and can be removed. Moreover, being manufactured to a standard in the works at Crewe, they are of uniform excellence, both in material and workmanship. About 6,000 yards of this rodding is turned out on an average every month, is sawn off to 18-feet lengths, and, when laid down, is jointed by means of fish-plates, secured by six-inch bolts, the fish-plates being rolled to a section to fit the channel of the rod, and the bolt holes drilled by a multiple drill. After being laid down, the rodding receives a coating of red lead and a second coat of red oxide paint, which gives it a smart appearance, and is found to be a good preservative.
For lighting the signal lamps at night, gas is used in the neighbourhood of large towns, where it is readily obtainable; but by far the greater number are lighted with petroleum oil, a large number of spare lamps being kept always on hand to provide for cases of failure. The signalling of the London and North-Western Railway as it exists to-day has involved the erection of 1,400 signal cabins, containing some 30,000 levers, and of 16,000 signals. The steel rodding used to actuate the points would form a continuous rod from the Land's End to John 0'Groat's, while the wires which work the
