short lengths, not only to disturb the ground as little as possible, but also to ensure perfect supervision, as if the work is not carefully and uniformly constructed, localization of water will ensue. The extent of a slip will to some extent govern the remedy. Simple open stone-filled drains, 2 to 4 feet in width, and 1 foot to 2 feet in depth, extending from the base to the top, may be sufficient for shallow cuttings or embankments, such as 10 to 15 feet, and larger and deeper trenches above those depths or heights, and complete drainage of and around the slipped earth, and division of it by means of drains and pipes. In countries where there is an excessive rainfall in a short time, it has been found necessary to catch as much of the surface flood waters and torrential streams as possible, and to reduce their velocity before passing through an embankment or down a cutting, and to provide a pond or “tumbling bay” at the base of a waterfall for such purpose, or to erect dams, when the force is not too great, so as to arrest and lessen the velocity of the flow. Without such precautions, flood waters will erode the earth, and the beds become gradually deeper; and walls at the toe, culverts, and dry stone filling across the whole width of an embankment, and stone covering upon the slopes where water issues or flows may be required. Catchment reservoirs have also proved of use in controlling the surface waters before they reach a cutting or embankment, and in permitting them to be controlled. Many of the chief causes of slips in embankments are enumerated in Chapter I., &c. Some of the most important operations to prevent slips in an embankment are to thoroughly drain its seat, prevent a flow upon the surface of the original ground, percolation of drainage waters into its lower part and filtration of rain-water at the crown, and to generally protect the surface.