Two men were taking their first ever train trip. A vendor came down the corridor selling bananas which they’d never seen before, so each man bought one.
The first man eagerly peeled the banana and bit into it just as the train went into a tunnel.
When the train emerged from the tunnel, he looked across to his friend and said: “I wouldn’t eat that if I were you.”
“Why not?” the friend asked.
“Well, the man said. “I took one bite and went blind for half a minute.”