In point of simplic'ty, the plant shown in Fig. 143 represents a water system that answers every purpose of a cottage and yet is only an elevated tank for storage of water, combined with a house force pump. The tank in this case may be made of wood or metal and is open at the top. The water is sent into the tank by the pump, and gravity furnishes the force for carrying it to the fixtures in the kitchen and bathroom.

In using a tank of the kind shown in the drawing, provision should be made for the possibility of leakage. This is arranged for by having the tank set in a shallow pan, so constructed that in case of accident the water may be carried away without doing damage. This type of plant is not usually employed in cold climates, unless some provision is made to prevent the water in the tank from freezing. Tanks of this kind are sometimes used in cold climates but a much more desirable plant for the purpose is described below. In Fig. 143 the water from the cistern W is raised by the pump P, which also forces it into the tank above the kitchen. The gravitational force given the water, because of its elevated position is all that is necessary to carry the water to the fixtures in the bathroom and kitchen sink. As shown in the drawing, it furnishes a complete water system that will perform all of the requirements of water distribution for a small family.

Fig. 143. - Sectional view of a cottage containing a simple gravity water-supply plant.

The pipes from the range boiler are attached to the water heater, which forms a part of the kitchen range as explained on pages 116 to 120. It receives the supply of cold water directly from the tank through the pipe marked C, and the hot water from the range boiler is supplied through the pipe H. Cold water is also taken from the tank directly to each of the cold-water taps.

The pump P is a house pump, such as is shown in Fig. 130. It is a small force pump, designed to suit the conditions of domestic use and is made to send water into the sink or into the supply tank as desired.