A three rotor Enigma enciphering machine circa 1940-1941 realised £60,000 ($96,240) at Bonhams London on October 29.
The device saw an increase of 20% on its estimate of £30,000-50,000 ($48,135-80,225). It featured the original three rotors along with matching serial numbers.
Enigma machines were used by axis forces to send coded messages during the second world war.
The Allies set up a number of listening stations, most at Bletchley Park - where mathematicians, including Alan Turing, worked to decode the messages.
The successful deciphering of the code considerably shortened the war and saved thousands of lives.
Another Enigma machine in the sale realised £57,500 ($92,316) against an identical estimate - up 15%.
In 2011, an Enigma machine used in the 2001 film Enigma sold for £133,250 ($208,137) - a world record price for such a device at auction.
We have this photograph signed by Guy Gibson, leader of the Dambusters raid in 1943.
The auction featured a variety of mechanical instruments, including a Jacques Bruguier singing bird box.
The silver and enamel box features a feathered bird which moves and sings, and was made in Switzerland in around 1835.
Work by Bruguier proved popular, with another bird box circa 1865 realising £33,750 ($54,185). It features an alpine scene on the lid along with fine enamelling and engraving.
Another box from the 1830s realised £22,500 ($36,123).
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