Signalman Job

[Sid]

Gary wants a job as a signalman on the railways. He is told
to meet the inspector at the signal box.
The inspector puts this question to him: "What would you
do if you realized that two trains were heading for each
other on the same track?"
Gary says, "I would switch the points for one of the trains."
"What if the lever broke?" asked the inspector.
"Then I'd dash down out of the signal box," said Gary,
"and I'd use the manual lever over there."
"What if that had been struck by lightning?"
"Then," Gary continues, "I'd run back into the signal box
and phone the next signal box."
"What if the phone was engaged?" "Well in that case,"
persevered Gary, "I'd rush down out of the box and use
the public emergency phone at the level crossing up there."
"What if that was vandalized?" "Oh well, then I'd run into town
and get my uncle Bill." This puzzles the inspector, so he asks,
"Why would you do that?"
"Because he's never seen a train crash."