An auction of scientific, technological, and musical instruments, soon to be held at Bonhams Auction House in the UK, will headline with a 1941 M4 Enigma machine used by the German military during World War II to send encrypted messages. Unlike the 3-rotor machines whose cipher codes were famously broken by those working at Britain’s Bletchley Park during the war, the 4-rotor model heading to auction is among the rarest of the rare, and is sure to command a high price. Besides cipher machines, however, the sale also offers a range of unusual and sought after examples of scientific instruments and musical automata that should also attract a great deal of interest. We take a look at a few prime examples.

Gizmag recently reported on the sale of an M3 Enigma machine at Sotheby's, which went for a cool £149,000 (US$232,015). Largely intact apart from a missing bulb and some surface rust, this model was extremely sought after by collectors, this being reflected in its high sale price. The M4 model from Bonhams, however, is a four-rotor machine that was produced in even smaller numbers and – after the concerted effort to destroy Enigma machines by the German army as they retreated – is an exceptionally rare model indeed.

Equipped with a standard qwertz keyboard, these machines represented an exceptionally larger combination of codes than possible in a 3-rotor model. As a consequence, British code breakers did not put their code-breaking machines to work to eventually decipher the possible combinations. Instead, the British armed forces relied on more conventional techniques by raiding German U-boats and weather ships and taking their code books.

Not distributed widely before the conflict was over, the very rare four-rotor M4 Enigma machine has an estimated auction value of between £80,000 - £120,000 ($122,000 - $183,000). Along with this very rare enigma are a range of other enciphering machines from before WWII and on into the 1960s, including a Swedish Hagelin B-21 cipher machine from 1932, and a Falka M-125 three-rotor cipher machine (£7,000 - £10,000/$10,670 - $15,250) employed by Soviet Russia and Warsaw Pact countries during the Cold War.

"It's unusual to find so many different types of cipher machines in one sale," says Bonhams' technology specialist Jon Baddeley. "The German Enigma is, of course, well known, but the others are fascinating variations on a theme and reflect the central role of protecting intelligence before, during and after World War II."

Among the other items set for sale at Bonham's are a group of orreries, lunariums, and tellariums that – when a a handle is cranked or a clockwork mechanism set in motion – show the orbit of planets and moons, along with their declinations and phases. The set for auction at Bonhams is a rare Matthew Berge brass combination valued at an auction price of £50,000 - £70,000 ($76,000 - $106,000).

Other interesting objects of note in the sale include a spherical glass orb "sunshine recorder" that used the rays of the sun shone through it and magnified to burn into specific sets of paper placed on a tracking mount to indicate the amount of sunshine received on any given day. Looking like something straight out of a 1950s B-grade science fiction movie, this handsome object would take pride of place on any desk. And, at an auction estimate of around £300 - £400 ($458 - $610), a bit of a bargain compared to some other of the items on sale.

If astronomical history and instruments is your passion, there are also a range of celestial and terrestrial telescopes up for grabs. Included in these is yet another rare item in the form of a 5-inch brass reflecting telescope made in England around 1770. Unusual in contrast to the largely refracting telescopes of the day, this instrument adjusts the focus of its primary mirror via a long shaft that extends from near the eyepiece to the top of the telescope. It's estimated to fetch around £2,000 - £3,000 ($3,050 - $4,575).

With many more items of historic and technical interest going under the hammer – from musical automata that play tunes and move in time, to scientific equipment once the cutting-edge instruments of their day – the auction at Bonhams Auction House will be held on Oct. 27 in Knightsbridge, London.

Source: Bonhams

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