A three-rotor WWII Enigma machine from 1941 is to lead a sale of scientific and mechanical instruments at Bonhams London on May 20.
The lot, valued at £40,000-60,000 ($67,884-101,826), was produced for the Luftwaffe. It features a panzerholz (wood/metal laminate) case in comparison to the oak case used by the Wehrmacht throughout the war.
The cracking of the Enigma code by Alan Turing's team at Bletchley Park enabled the Allies to listen in on Nazi communications - a source of intelligence that was codenamed Ultra and remained top secret until long after the end of the war.
In October last year, a similar machine sold for £60,000 ($96,000) at Bonhams London.
Check out our military memorabilia here.
A George Adams Junior combined planetarium and tellurium is estimated at £30,000-40,000 ($50,892-67,856).
The piece was built in the late 18th century and offers a detailed model of the solar system and the orbits of the planets.
It includes the recently discovered Uranus, which was initially called the "Georgian Planet" by its discoverer William Herschel in honour of King George III.
The 19th century German astronomer Bode would later rename it in line with the Greek mythological theme.
Other lots include a late 18th century telescope attributed to the pioneering optician John Dolland that carries an estimate of £18,000-24,000 ($30,547-40,730).
We have this signed copy of the Ten Special Commandments for a Would-Be Planet Hunter by Clyde Tombaugh, who discovered Pluto.
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