SCIENCE OF HOME AND COMMUNITY 



the well and by means of a pump the water is pumped into 

 the tank. At the same time the pump compresses the air 

 above the water in the tank, and this compressed air forces the 

 water from the tank up through the pipes leading to the vari- 

 ous parts of the house. Arrangements are made to pump new 

 air into the tank to take the place of that dissolved by the 

 water. The pumping may be done by hand, by windmills, 



by gasoline engines, or 

 by electric motors. 

 Where electricity is 

 available, the motor is 

 the most convenient, 

 as it may be arranged 

 to work automatically 

 according to the air 

 pressure, both to start 

 and to stop. 



Hot-water tank. Run- 

 ning water in the house 

 allows of a constant 

 supply of hot water 

 during the cold weather 

 when the fires are burn- 

 ing. The cold water 

 is first brought into 

 the hot-water tank by 

 means of a pipe extending nearly to the bottom of the tank. 

 The water is heated by passing through coils of pipes that 

 are placed in the stove or furnace. From here it passes 

 back to the tank, where it accumulates in the upper half 

 and is drawn off from the top and circulates through the 

 house. 



Fie. 19. Hot-water tank and water front in 

 range. 



