Billy Bob wanted a job as a signalman on the railways. He was told to meet the inspector at the signal box.

The inspector asked, What would you do if you realized that two trains were heading for each other on the same track?

Billy Bob replied, I would switch the points for one of the trains.

What if the lever broke? asked the inspector.

Then Id dash down out of the signal box, said Billy Bob, and Id use the manual lever over there.

What if that had been struck by lightning?

Then, Billy Bob continued, Id run back into the signal box and phone the next signal box.

What if the phone was busy?

Well in that case, persevered Billy Bob, Id 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 Id run into town and go get my Uncle Lester.

This puzzled the inspector, so he asked, Why would you do that?

Billy Bob answered, Well, Uncle Lester aint never seen a train wreck!