A pair of secretly-modified handcuffs used by Harry Houdini is to go on sale by auction next week.
While Houdini is believed to have carried out most of his escapes using unaltered equipment, this particular pair, probably used in his underwater escapes, hides a secret. When held over a flame, immediately before Houdini's act, the spring mechanism loosens in such a way that when they're turned upside down they snap open.
"He did a variety of water stunts and it is a possibility that these handcuffs could have been used in the Chinese Water Tortune trick, which was seriously dangerous," says auction house Dreweatts & Bloomsbury's specialist in conjuring and performing arts Michael Heseltine.
"He would have needed to have that precaution to make sure he could get out; the audience wouldn't have known because his tricks were done in a matter of seconds."
The handcuffs, up for auction next Thursday, are accompanied by a letter from the magician Billy McComb, who discovered their secret after acquiring them in 1960 from the widow of Houdini's brother, Theo Hardeen. They are the only pair owned by Houdini known to have been treated in this way.
However, as he wrote in 1910, "you can open the majority of the old-time cuffs with a shoestring. By simply making a loop in the string, you can lasso the end of the screw in the lock and yank the bolt back, and so open the cuff in as clean a manner as if opened with the original key."
The rather rusty handcuffs, together with the letter, are expected to reach £2,000-3,000.
Other items also owned by Houdini will go under the hammer the same day. They include a pair of leg irons, estimated at £2,000-3,000, and a round barrel screw key padlock that's expected to fetch£1,000-1,500. Cheaper is Houdini's personal copy of Hudson Tuttle's Arcana of Spiritualism, expected to sell for £250-350.