Page:The Working and Management of an English Railway.djvu/63

rubble or pipe drains; if it is not of a porous character as, for instance, stiff clay or rock, the surface should be formed with a section similar to that of a well-constructed macadamized road, so as to throw the water quickly off its surface to the side ditches. Upon such a formation should be placed a layer of bottom ballast of uniform size and durable quality, free from dirt or any substance which absorbs and retains moisture. Upon the bottom ballast the sleepers will be laid, and with a sufficient quantity of top ballast, which should be equally clean and durable, although, preferably, of smaller size, the line will be raised and adjusted to its intended level, the plate-layers, in laying the sleepers, taking particular care to obtain a uniformly solid and level bed for each sleeper, so that it may take precisely its proper share—no more and no less—of the weight of the passing trains. Skill and attention displayed at this stage meet with their due reward, and much subsequent trouble and anxiety is saved to the permanent way inspector, who has a length of road to maintain, if he takes care that his sleepers are not bedded on irregularly-sized lumps of stone, that his chairs are fixed to a uniform gauge, and that the sleepers are placed at right angles to the direction of the line, and well packed, or beaten up, as firmly under one rail as the other. He should see that his rails are not bent in unloading, that all crooked or defective fish-plates, spikes, and screws are rejected; that his curves are of uniform curvature, and with super-elevation proportioned to the radii, and that many other apparently insignificant precautions are not neglected, all of which contribute to the construction of a sound and perfect permanent way over which