单项选择题

Questions 51-57 are based on the following passage. Harry Houdini, who died in 1927, was the entertain-ment phenomenon of the ragtime era. He could escape from chains and padlocks, from ropes and canvas sacks. They put him in a strait -jacket and hung him upside down from a skyscraper and he somehow untied himself. They tied him up in a locked packing case and sank him in Liverpool docks.Minutes later he surfaced smiling. They locked him in a zinc-lined Russian prison van and he emerged leaving thedoors locked and the locks undamaged. They padlocked himin a milk churn full of water and he burst free. They put himin a coffin, screwed down the lid, and buried him and.., well,no, he didn蒺t pop up like a mole, but when they dug him up more than half an hour later, he was still breathing. The alternative explanation for his feats of escapism was that Houdini could do unnat原ural things with his body. It is widely held that he could dislocate his shoulders to escape from strait-jackets, and that he could somehow contract his wrists in order to escape from handcuffs. His ability to spend long periods in confined spaces is cited as evidence that he could put his body into suspended animation, as Indian fakirs are supposed to do. This is all nonsense. If you ever find yourself in a strait-jacket, it蒺s difficult to imagine anything less helpful than a dislocated shoulder. Contracting your wrists is not only un原helpful but, frankly, impossible because the bones of your wrist are very tightly packed to原gether and the whole structure is virtually incompressible. As for suspended animation, the trick of surviving burial and drowning relies on the fact that you can live for short periods on the air in a confined space. The air shifted by an average person in a day would occupy a cube just eight feet square. The build-up of carbon monoxide tends to pollute this sup原 ply, but, if you can relax, the air in a coffin should keep you going for half an hour or so. In other words, there was nothing physically remarkable about Houdini except for his bravery, dexterity and fitness. His nerve was so cool that he could remain in a coffin six feet underground until they came to dig him up. His fingers were so strong that he could undo a buckle or manipulate keys through the canvas of a strait-jacket or a mail bag. He made a comprehensive study of locks and was able to conceal lock-picks about his person in a way which fooled even the doctors who examined him. When they locked him in the prison van he still had a hacksaw blade with which to saw through the joins in the metal lining and get access to the planks of the floor. As an entertainer he combined all this strength and ingenuity with a lot of trickery. His stage escapes took place behind a curtain with an orchestra playing to disguise the banging and sawing. The milk churn in which he was locked had a double lining so that, while the lid was locked onto the rim,the rim was not actually attached to the churn. Houdini merely had to stand up to get out. The mail sack he cut open at the seam and sewed up with similar thread. The bank safe from which he emerged had been secretly worked on by his mechanics for 24 hours before the performance. All Houdini蒺s feats are eminently explicable, although to explain them, even now, is a kind of heresy. Houdini belongs to that band of mythical supermen who, we like to be原 lieve, were capable of miracles and would still be alive today were it not for some piece of low trickery. It蒺s said of Houdini that a punch in his belly when he wasn蒺t prepared for it caused his burst appendix. Anatomically, it蒺s virtually impossible that a punch could punc原ture your gut, but the story endures. Somehow the myth of the superman has an even greater appeal than the edifice of twenty-first century logic. Questions: It appears that Houdini was able to escape from a strait-jacket by ______.