It may become necessary to excavate or trim a slope to a steeper inclination than that which would otherwise be adopted and is considered to be its angle of repose, in order to widen a railway between the fences, or enlarge a station. Then, pre-eminently the question of the effects of a slip demand attention. The great majority of railway stations are located prior to the commencement of, or as the works progress, but additional accommodation which, for reasons of economy must proceed _pari passu_ with the development of a district, is usually required some time after a railway has been opened for public traffic, and it may be imperatively necessary to confine the works within the boundaries of the land originally purchased. Consideration of the several chapters in this book will recall to the mind the chief points to be regarded. Fortunately, stations are seldom placed in deep cuttings or upon high embankments; but frequently when a station is opened, houses will be erected around it, thus causing any movement of the ground to be of serious moment and dangerous. Assuming the railway must be widened within the original fences, the position of the toe of the slope is fixed, and also that of the top of the slope. The questions then in the case of a cutting are principally:— 1. Will the slope be too precipitous for the earth to stand at one inclination? 2. Can it be made sufficiently steep for 5 or 6 feet from the top to obtain an inclination for the lower portion at which it will have permanent stability? 3. Can the earth be made to repose if the face is evenly protected under circumstances 1 and 2? 4. Is it necessary to erect a retaining wall to a distance a few feet from the original surface of the ground? 5. If a wall be necessary, what should be its lowest height consistent with the stability of the unsupported inclined earth above it?