The fact that everybody enjoys a good mystery explains why magicians are such popular entertainers. We all know that a magician does not really depend on'magic'to perform. his tricks, but on his ability to act at great speed. However, this does not prevent us from enjoying watching a magician produce rabbits from a hat, swallow countless eggs, or saw(锯)his wife in two. Probably the greatest magician of all time was Harry Houdini who died in 1926. His real name was Enrich Weiss, but he adopted the name 'Houdini' after reading a book which influenced him greatly. This had been written by a famous magician called Robert Houdini. Houdini mastered the art of escaping. He could free himself from the tightest knots(最牢固的结) or the most difficult locks in seconds. Although no one really knows how he did this, there is no doubt that he had made a close study of every type of lock ever invented. He would carry a small steel needle-like tool fastened to his leg and he used this instead of a key. Houdini once asked the Chicago police to lock him in prison. They bound him in chains and locked him up, but he freed himself in an instant. The police accused him of having used a tool and locked him up again. This time he wore no clothes and there were chains round his neck, waist, wrists(手腕) , and legs but he again escaped in a few minutes. Houdini had probably hidden his 'needle 'in a wax-like substance and dropped it on the floor in the passage (过道). As he went past, he stepped on it so that it stuck to(粘在) the bottom of his foot. His most famous escape, however, was altogether astonishing. He was heavily chained up and shut in an empty wooden box the lid of which was nailed down. The box was dropped into the sea in New York harbor. In one minute Houdini had swum to the surface. When the box was brought up, it was opened and the chains were found inside. Magicians' successful tricks mostly depend on the fact that they can______.