A passenger in a taxi leaned forward and tapped the driver on his shoulder, who screamed in terror and lost control of his car, which swerved across the road, bounced up a kerb and came to a halt just one foot away from a large plate glass window.
The frightened passenger apologised to the driver and said that he didn't think a mere tap on the shoulder would produce such a reaction.
And the driver replied, "No, no, I'm sorry - it's entirely my fault. Today is my first day on the job. For the last twenty-five years I've been driving a hearse..."