A properly constructed clay court is usually more expensive than a turf court, for the ground must be excavated to a depth of eight or ten inches so that a foundation can be made of stones, cinders, or gravel. The drainage problem is one of the most important in laying out clay courts, and, if overlooked, the most promising court will soon become a place for pools to collect. In time it will settle in spots and need constant repairs to keep it in any kind of condition. While it may take a good engineer to build a clay court suitable for professional playing, a novice can do work that is suitable for all ordinary purposes. As the cost of building one is largely due to the labor item, it may be achieved at one-third the total expense through the coÖperation of several members of the family in excavating and hauling material to the site.

To make a good dirt court it will be necessary first to dig off the surface to a depth of at least one foot, and level it roughly with a spirit level. The cost of this excavation in ordinary dirt is not more than ten or fifteen dollars, but where rocks must be blasted away the cost may be five or six times as much.

After leveling the foundation, a six-inch layer of trap-rock, such as is used in macadamizing roads, or any broken stones ranging in size from a walnut to an egg, should be placed in the excavation. This must be leveled off also to keep the grade. An uneven tennis court will never give satisfaction. Before the next layer of gravel is placed on the trap-rock, provision must be made for drainage. There are several methods of draining a court, depending greatly upon the nature of the soil and the preference of the owners.

For ordinary soil a good method is to lay the drain pipe near the net and at right angles to the courts, dividing them in half. The drain pipe may consist of terra cotta sewer pipes cut in half or terra cotta gutters, such as are used on tiled roofs. They are laid parallel with the net and filled with loose stones. The drains are tilted sufficiently to carry the water off at the sides or to a receptacle in the center. Sometimes a barrel is sunk in the middle and filled with stones, and the drain pipes empty into it.

Another common method is to drain the courts at the end. In this case the court at the net is two inches higher than at the ends, and on porous soil this will be sufficient to carry off the water. When the drain pipe is placed near the net the tilt from the ends toward the center should be from one to two inches.

We have more difficult drainage problems in very thick loam and clay soils. Artificial drainage of a more elaborate nature is required here, or else the courts will be muddy and sticky for days after rainstorms. Drain pipes must be laid under the courts at various places, and tilted toward one particular point. The open drain pipes are laid down before the trap-rock is placed, and filled with broken stones so they will not clog up with dirt. Two or three of these lines of open pipe should be placed on either side of the net. They should run from the ends of the courts toward the net and drain into the gutter that has been placed under the net. The number of these drain pipes depends upon the sticky nature of the soil. Four parallel rows of them on either side of the net should be sufficient for the poorest kind of soil.

When the drain pipes are laid, and the courts properly leveled with the trap-rock foundation, a three-inch layer of coarse gravel or fine broken stone should be spread over the surface. This must be pounded and hammered down and watered. The water will tend to show any weak places where settling is liable to occur, and the depressions thus formed must be filled up with fresh material. When this layer of coarse gravel has been leveled, pounded, and settled, the top layer, of sandy loam and clay mixed, should be applied. This finishing layer should be at least three inches thick, and four or five is better. Sandy clay and loam must be mixed for the top-dressing, but the proportion of each depends upon the nature of the clay. If the clay is very sticky it will require more sand. It needs to be sufficiently porous to permit the water to pass through easily, and yet not so porous that the surface is too soft. If there is not sufficient sand the surface will be sticky after a rainstorm. For ordinary purposes one part of fine sand to four parts of clay make an ideal finishing surface, but sometimes one and a half parts of sand have to be used.

When the finishing surface is laid it should be leveled off and rolled repeatedly. Watering is also essential, but a good rain will do wonders to settle the surface. Faults and depressions will then develop, and they can be corrected by filling in with new material. Also, if the surface is found to be too sticky, add a little more sand to the top and work and roll it down. It may take several weeks to perfect the top surface of the court so that it is rain-proof.