Two men were going to go on a journey by rail.

They'd never been on a train before, and were rather nervous. They decided to take some oranges on the train with them, as eating oranges might help take their minds off the journey.

The men bought their tickets and got on the train. They bought the cheapest tickets, which were for the third class carriage. Third class had bare wooden seats, and no lights. In spite of this, the two men began to quite enjoy the journey.

After half an hour or so, the two men decided to have an orange each.   Just as the first man began to eat, the train entered a tunnel.

"Have you eaten your orange yet?" asked the first man.

"No," said the   second man.

"Well don't touch it!" said the first man. "I took one bite and went blind!"