This being done, a steam-pump, far less formidable than many which are in profitable use in Europe for the same purpose, would empty, and keep empty, the present bed of the river, which would form a capital outlet for the drainage of the whole area. Twenty thousand acres, of the most fertile land, would thus be added to the available area of the State, greatly increasing its wealth, and inducing the settlement of thousands of industrious inhabitants. As the circumstances under which upland water reaches lands of the class under consideration vary with every locality, no specific directions for the treatment of individual cases can be given within the limits of this chapter; but the problem will rarely be a difficult one. *The removal of the rain-fall and water of filtration* is the next point to be considered. So far as the drainage of the land, in detail, is concerned, it is only necessary to say that it may be accomplished, as in the case of any other level land which, from the slight fall that can be allowed the drains, requires close attention and great care in the adjustment of the grades. The main difficulty is in providing an outlet for the drains. This can only be done by artificial means, as the water must be removed from a level lower than high-water mark,—sometimes lower than low-water. If it is only required that the outlet be at a point somewhat above the level of ordinary low-water, it will be sufficient to provide a sufficient reservoir, (usually a large open ditch,) to contain the drainage water that is discharged while the tide stands above the floor of the outlet sluice-way, and to provide for its outflow while the level of the tide water is below the point of discharge. This is done by means of sluices having self-acting valves, (or tide-gates,) opening outward, which will be closed by the weight of the water when the tide rises against them, being opened again by the pressure of the water from within, as soon the tide falls below the level of the water inside of the bank. The gates and sluices may be of wood or iron,—square or round. The best would be galvanized iron pipes and valves; but a square wooden trunk, closed with a heavy oak gate that fits closely against its outer end, and moves freely on its hinges, will answer capitally well, if carefully and strongly made. If the gate is of wood, it will be well to have it lie in a slightly slanting position, so that its own weight will tend to keep it closed when the tide first commences to rise above the floor, and might trickle in, before it had acquired sufficient head to press the gate against the end of the trunk.