Scale.—What causes scale to form in the boiler and what effect does scale have on the boiler? [II. 370].
Preventing scale.—What are the principal methods employed to prevent the formation of scale in the boiler? [II. 370].
Horizontal heater.—What advantage does a horizontal heater possess? [II. 370].
Dirty gauge glass.—What should be done to the gauge glass if the feed water is dirty? How many times a day should the gauge be blown out? [II. 370].
Priming.—What is the priming or foaming of the water in a boiler? What are the known causes of priming? Why is priming wasteful? Can blowing off at the safety valve cause priming? What are other causes of priming? How can priming be detected? What would you do to stop priming? What would you do to prevent priming? What parts of the engine would you attend to if the boiler primes? [II. 370].
Low water.—What would you do if the water got dangerously low in the boiler? In such a case how would you regulate the dampers? What do you consider dangerously low? What is blowing down a boiler? [II. 370].
Cleaning a boiler.—How often would you clean a boiler? [II. 371].
Water falling.—What would you suppose was going wrong if the pump was kept going and the water still fell in the boiler? [II. 370].
Empty pump.—What causes a pump to fail? [II. 370].
Blowing down.—How much would you blow down a boiler? How low should the pressure get before the water is let out? What would be the result if the boiler was blown off under a high pressure? What would you do after the water is all out of the boiler? [II. 371].