In cases of extreme inspection, Houdini could manipulate the needles to be hidden beneath his tongue. He could also move the needle to the area between his upper gum and lips and move them back after inspection. In drawing his lower lips and pulling his cheeks outward, his fingers would cover the needles hidden by his lower lip.

Most suspicion was directed toward the back portion of the upper gums and Houdini would simply draw his cheeks wide with his little fingers to give a thorough view of the area. In showing his mouth, he would draw his upper and lower lips away from his gums and teeth. This required a great deal of thought and skill.

At this point, Houdini's job was simply to deceive the committee. This prevented any real danger of having the needles coming loose from the thread, which could have injured Houdini. By tying a note on each side of the needle, a little 'play' was allowed, so that the needles were loose, appearing to be normally threaded. To perform this trick, Houdini would simply place a length of thread already threaded with needles and place them between his lips and gums before his mouth was examined. He begins by placing the needles and thread on his tongue and appears to swallow them. In this trick, Houdini swallows 50 to 100 needles, 20 yards of thread and brings them all up threaded, after his mouth and throat have been inspected by a committee. Houdini brought the 'East Indian Needle Trick' from the obscurity of sideshows to popular culture in the early 1900s.

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