Page:The Working and Management of an English Railway.djvu/197

 in the management of a railway than all others put together, and that is the prevalence of fogs in this country. When one of these unwelcome visitations descends upon us, although the telegraph still remains, the whole system of visible signals is, as it were, blotted out, and it is easy to realise how extremely difficult this must render the working. The greatest caution has to be observed, the speed has to be reduced, and more or less delay is inevitable in the interests of safety, which, after all is, of course, the first and last consideration. To admit of the trains running while the signals are invisible, a system of what is called "fog-signalling" has been devised, and a brief description of this system, which is as simple as it is perfect, may do much to reassure any of our readers who may chance to find themselves performing a journey by an express train during a fog. At such a time the platelayers are perforce idle, since the permanent way is not allowed to be interfered with until the weather clears, and these men for the most part furnish the ranks of the fog-signalmen. Directly a fog comes on, a man is stationed at the foot of each distant signal, and becomes, in fact, a living signal-post. As soon as the signal-arm is raised to "Danger," he places upon the rails two detonating signals, which are exploded by the engine of a train passing over them, and the driver of the train is thus apprised that the signal, although invisible to him, is at "Danger," and he must act accordingly. If the signal is lowered to indicate that the line is clear before any train approaches, the fog-signalman at once removes the detonators, but replaces them as soon as the signal is again raised to "Danger."

Each man is provided with a hut to shelter him, a fire