The Ordering of the Tile.—The main line from the outlet up to the silt-basin, should be of 3-1/2-inch tiles, of which about 190 feet will be required. The main drain A should be laid with 2-1/4-inch tiles to the point marked m, near its upper end, as the lateral entering there carries the water of a spring, which is supposed to fill a 1-1/4-inch tile. The length of this drain, from the silt-basin to that point is 575 feet. The main drain C will require 2-1/4 inch tiles from the silt-basin to the junction with the lateral, which is marked C 10, above which point there is about 1,700 feet of drain discharging into it, a portion of which, being a stone-and-tile drain at the foot of a rock, may be supposed to receive more water than that which lies under the rest of the land;—distance 450 feet. The main drain E requires 2-1/4-inch tiles from the outlet to the point marked o, a distance of 380 feet. This tile will, in addition to its other work, carry as much water from the spring, on the line of its fourth lateral, as would fill a 1-1/4-inch pipe.[12]
The length of the main drains above the points indicated, and of all the laterals, amounts to about 12,250 feet. These all require 1-1/4-inch tiles.
Allowing about five per cent. for breakage, the order in round numbers, will be as follows:[13]
3-1/2-inch round tiles 200 feet.
2-1/4-inch round tiles 1,500 feet.
1-1/4-inch round tiles 13,000 feet.
3-1/2-inch round tiles 1,600
2-1/4-inch round tiles 13,250
Order, also, 25 6-inch sole-tiles, to be used in making small silt-basins.
It should be arranged to have the tiles all on the ground before the work of ditching commences, so that there may be no delay and consequent danger to the stability of the banks of the ditches, while waiting for them to arrive. As has been before stated, it should be especially agreed with the tile-maker, at the time of making the contract, that every tile should be perfect;—of uniform shape, and neither too much nor too little burned.