=158. The Flushing Tank.= The flushing tank (Fig. 84) is a reservoir to hold sufficient water to cleanse the bowl. In one type of tank, water is retained in the tank by a plug held in place by the weight of the water in the tank. By a lever on the outside of the tank, this plug is lifted when the bowl is to be flushed, and it stays open until all the water flows out of the tank. When the water has all left the tank, the plug falls back into the hole and fresh water flowing into the tank holds it in place, as there is nothing in the pipe below to make it float upward. Working at the same time with the plug is a valve in the water supply pipe, attached to a large hollow float. The valve opens as the water flows out of the tank, and closes as the tank is filled. This valve is operated by the float floating on the surface of the water. As the water flows out of the tank, the float falls, opening the valve and letting in water. As the tank fills, the float rises to the top of the tank and shuts off the valve. If the float catches so that it fails to rise and fall, or becomes disconnected from the valve, it will not operate the valve. There is an overflow pipe in the tank which carries off all water rising above a certain level in the tank. This prevents the tank from overflowing when the valve fails to turn. [Illustration: FIG. 84. Diagram of flushing tank.] =159. Repairing the Flushing Tank.= When the water continues to flow into the tank, take off the cover of the tank and examine the valve and ball to see why they are not working properly. If disconnected or caught, remedy the trouble. If the plug fails to stop the flow of water out of the tank, water will also continue to flow into the tank. To remedy this temporarily, push the plug down over the outlet and also note the reason why it has not fallen back automatically. If worn, it may have to be replaced with a new one. There should be a valve to close the pipe to the tank. With this valve, much water can be saved in time of trouble, and greater convenience may be had in remedying difficulties with the devices inside the tank. QUESTIONS FOR PART V 1. How does a pump lift water from a well? 2. How do pumps differ in construction? 3. What care should be given a pump? 4. When is a water filter useful? When dangerous? 5. What is a pressure tank? How does it operate? 6. Describe two kinds of water heaters. What precautions should be taken with each kind of heater? 7. Describe a water faucet. Try to replace an old washer with a new one. 8. Have you ever cleaned the overflow to a tub or basin? Should they be cleaned? 9. What are traps? What may cause them to fail to work? 10. How would you select a good trap? How would you clean it? 11. Describe the construction of a septic tank. What is the action that takes place in a septic tank? What care should be given to it? 12. Examine the tank to a water closet. How does it operate? PART VI LAUNDRY EQUIPMENT.