A rare German Enigma machine is up for auction at Sotheby's.
The lot is among the highlights of an English literature, history, children's books and illustrations sale in London on July 14. It carries an estimate of ?�50,000-70,000 ($76,885-107,639).
British mathematician Alan Turing famously headed up the Bletchley Park team that cracked the Enigma code.
The auction house describes it as "a rare and exceptionally well-preserved example of the famous German cipher machine, a remarkable achievement of design, defeated through one of the greatest efforts of human ingenuity seen in the last hundred years.
"Few Enigma machines survived the War intact: the Germans destroyed them as they retreated, and for decades after the war governments around the world kept close control over Enigma technology (indeed two of Turing's wartime papers on cryptography remained classified until 2012)."
In the past Enigma machines have sold for significant sums at auction, with one example setting a $269,000 world record at Bonhams earlier this year.
Other lots in the eclectic sale include an unpublished drawing by Winnie-the-Pooh illustrator EH Shepard that carries an estimate of ?�30,000-50,000 ($46,131-76,885).
Titled Owl Lived at the Chestnuts, an Old World Residence of Great Charm, the work dates to circa 1924-1928.
It was presented as a gift to the composer of the musical version of Winnie-the-Pooh in 1970.
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