clear the water as effectually and enable the soil to settle to its new state. The location of the sump should be at or about the lowest level of the ground well away from any wall or the dock area, and on the line of the greatest flow of the land waters or natural watercourse, thus, dealing with them before they reach the site of the works. In loose and almost all earth the foundations should be covered up quickly so as to preserve the natural condition of the soil. It is also important to offer every possible support to the earth to prevent initial movement, and slight assistance may afford the required strength. Unless there are cogent reasons to the contrary, the excavation for dock-walls is better executed in trenches, the frames of which being struck as the work progresses can be used again; the wall can thus be supported by the earth on either side, and no lateral thrust is brought upon the wall until it has set, and therefore the danger of bringing, perhaps, the greatest strain upon it when in an imperfectly solid condition is obviated, the back and top of the wall being protected from the weather, and any movement or slip of the earth prevented; hence a wall should act as quickly as practicable as a monolithic mass, and the material forming it be thoroughly bonded and set in Portland cement or the best hydraulic lime mortar, or be wholly of strong Portland cement concrete. The trench system of constructing dock-walls, covered ways, and all work below ground is the safest to adopt, and in loose soils or clay that expands and is quickly affected by atmospheric influences, and where there are buildings or the ground is weighted, the erection of side walls in trenches, and then the completion of the invert or arch is often the only way in which the work can be executed. Even should the formation be rocky, and the beds be inclined towards the site, the short 15 to 20 feet in length trench system is the best to adopt; and it may be advisable or necessary to work day and night in order that the ground may be left exposed for the least possible time and as machine mixed Portland cement concrete walls can be erected much quicker than masonry or brickwork, in such situations it is the best material to use. The excavation for the walls should be confined within the smallest limits, but no under-cutting should be allowed in the excavation trenches, or the portion undercut may strain the upper part and cause it to slip and subside.