The first of April is commonly known as April Fools’ Day, and it is customarily on this day to play a trick on a friend. If your friend falls into the trap, then he or she is an April Fool.It isn’t only children that like such jokes. Grownups like such pranks, too.

　　Even the media occasionally try to deceive the public with a clever April Fool story. Some years ago, for example, a famous joke was played on the radio. A scientific correspondent reported that strange gjoozoneogical changes had resulted in weaker gravity in different parts of Britain. He asked listeners to jump up and down and see if they could jump higher than they normally could. Many people did. The hundreds of calls the BBC received proved how successful the hoax was. Not until twelve o’clock did the BBC gently remind its listeners it was April Fools’ Day that day.

　　Making jokes only lasts until the noon of the day, the rule is rigid and everywhere acknowledged. Anyone who tries to make a fool after midday is a bigger fool than he who has been fooled. The late trickster is instantly rebuffed.

　　When did April Fool this custom start? According to a well-researched story of the origin of the day, it was started in 1545 by a rather unfortunate accident. A Norwegian scientist, Loof Lirpa, was staying in London, where he was trying to find the secret of how to fly.

　　The scientist was eccentric, but there was no doubt that he was clever. It seems that his experiments were successful: King Henry VIII received a letter from Mr. Lirpa, in which he announced that he had finally solved the secret of flight. He asked the king to be present at a demonstration flight at Westminster on April 1.

　　So the king and the leading politicians of the day stood ouside the Palace of Westminster on April 1, and waited for Mr. Lirpa to come flying past. But nothing happened-- and it became the tradition afterwards to play tricks on people in the same way on this day.

　　However, evidence proved later that Loof Lirpa was not playing a trick: he was in fact telling the truth. He had learnt how to fly-- the reason that he didn’t appear at Westminster was that his flying-machine had crashed into a tree, and he had been killed.It was a tragedy for science. The scientist, unfortu-nately, was very secretive. When he died, the secret died with him.

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