72. Q. What does it indicate when the smoke trails back over the train
and into the coaches after shutting off?

A. It indicates poor firing or a lack of understanding between the
engineer and fireman in regard to where the engine was to be shut off.

73. Q. Before shaking grates or dumping the ash-pan, what should be
observed?

A. That the engine is not passing over bridges or cattle guards,
crossings, switches, interlocking fixtures, or in yards. Fire on the
track should be extinguished promptly at places where ash-pans are
cleaned.

74. Q. Which is easier and more satisfactory on a long run, to stop and
clean the fire if necessary or to continue to the end of a long, hard
trip with a dirty fire?

A. Stop and clean the fire if necessary. It will save fuel and labor
during the remainder of the trip and may also save an engine failure.

75. Q. Should you examine the flues to see if they are stopped up and
leaking, and inspect the grate and grate rigging carefully before
leaving the engine at a terminal?

A. Yes, so they can be reported if necessary. Clean flues and grates
working well make a vast difference in the success of a fireman, and a
great many engine failures could be avoided by keeping the flues and
grates in proper condition.