The photograph shows a cistern, 6 by 6 by 12 feet, inside dimensions, with 8-inch walls, 6-inch floor, and 4-inch roof.
Dig a pit 12 inches deep, and of the size of cistern desired. Cover the bottom with a well tamped fill of gravel to a depth of 6 inches. Mix concrete 1: 2: 4 and place it to a depth of 2 inches over the surface of the fill. On top of this lay sections of heavy woven wire fencing. This wire should be laid in such a way as to extend 6 inches beyond the outside edge of foundation—the ends being bent up, so as to stand upright, 3 inches back from the edge of the concrete flooring already placed. Immediately lay the remaining 4 inches of concrete floor. Give the surface a finish with a wooden float to within 6 inches of edges.
Without delay, set the forms, made up in the required sections, resting the inside form on the concrete floor and the outside form on the ground. Place the inside form first. After setting the inside form, place woven fence wire, supporting it against the inside form by means of staples driven lightly into the form and holding the wire 4 inches away from it. Care should be taken in placing the concrete that the wire is kept near the outside of the concrete wall. This reinforcement is carried 1 foot beyond top of wall. The projecting wire mesh will later be used to tie the concrete roof to the side walls. The timber required for the forms will be 1-inch siding and 2 by 4 uprights, spaced every 18 inches.
In placing the concrete in the forms, it will be easier to leave off the two top feet of planking of outside form until the concrete reaches its level. Then add this planking and fill the two top feet. The concrete will probably have to be passed up to a man on top by means of buckets.
The luxury of soft water for the bath, and its advantages for laundry purposes, are understood better by farmers than by their city cousins. Cisterns were originally built in the ground, but a thinking farmer used concrete to build a cistern on top of the ground, no doubt taking the idea from the old-fashioned rain barrel. While it requires more forms and more reinforcement than a cistern built in the ground, yet the large cost of digging a deep hole is saved. As the water is piped to the house, direct water pressure is provided, thereby giving the farm-house all the advantages of a city water system.
Build a wooden platform inside the cistern, in the same manner as directed in [Underground Cisterns], page 69. The materials required for the concrete are 10 yards of crushed rock or screened gravel, 5 yards of sand, and 17 barrels of Portland cement.
