Removing scale.—How is scale removed in boilers? [II. 454].

Salinometer.—What is a salinometer? [II. 455].

Salt in sea water.—About how much salt does sea water contain? [II. 454].

Division plates.—What are division plates in boilers? [II. 455].

Intercepter.—What is the separator or intercepter of a marine boiler? [II. 455].

Boiler draft.—What causes the draft in a boiler? [II. 455].

Rapid wasting.—Where does the most rapid wasting occur in marine boilers? [II. 455].

Coal consumption.—About how much coal is consumed per square foot of grate in marine boilers? [II. 455].

Short of coal at sea.—If at sea and short of coal, what course would you pursue in order to save coal and get into port? [II. 455].

Boiler relief in extreme danger.—How would you relieve a marine boiler in case of the safety valve being locked down from some accidental cause, the engine also being disabled? [II. 455].