The fencing in of a line of railway serves the double purpose of defining the boundary of the company’s property, and of forming a barrier for the prevention of trespass of persons and animals on to the line. For our home lines, fencing is compulsory, and the same obligation exists on many foreign railways. In our colonies, and out in the far West of the United States, and in newly opened out countries, fencing, except near towns and villages, is rather the exception than the rule; people and animals roam at will from one side of the railway to the other wherever they find a convenient crossing place, and the cowcatcher of the engine has to be depended upon for throwing aside any animal which may be standing, or resting, on the line of rails at the passing of a train. The description of fence will be influenced by the locality, and the materials conveniently obtainable. Where stone is plentiful, perhaps brought forward out of the cuttings, and labour cheap, a masonry wall will be found a most suitable permanent fence. Any fence to be of service should not be less than four feet high. A wooden post and rail fence is much in favour in some districts, the posts being firmly set or driven into the ground, and four or five stout bars nailed on to, or set into, the upright posts. This fencing does not last very long, the pieces are small in size, and soon fail from decay. Quick or hawthorn hedges, when fully grown, make a good fence, but require careful attention to prevent gaps being made by roving cattle. They also require constant trimming and cutting. The quicks are generally planted in a mound formed by cutting a continuous ditch, or gripe, as shown in Fig. 65. The ditch serves as a drain to take away water running down the slopes of the embankments, small openings in the mounds, or drain pipes through them, forming leaders to conduct the water to the ditch or gripe. The outer edge of the ditch represents the boundary of the railway property, unless specially arranged otherwise. Galvanized iron-steel wire fencing, if not made too light, is strong and durable, and very easily kept in order.