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Cipher machine up for sale at 79th Auction of Hermann Historica GmbH

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Munich – The device is so rare that even the world's largest science and technology museum, the Deutsches Museum in Munich, was thrilled to receive one recently that had been excavated, heavily corroded and clearly not functional, as an archaeological find. Thus, the sale of the Schlüsselgerät 41 cipher machine is one of the highlights of the Spring Auction, which takes place from May 20-24. Dubbed the "Hitler Mill" owing to its crank mechanism, only a handful of functional devices still exist throughout the world. Bids are now invited from 75,000 euros for lot number 4401, a perfectly preserved specimen, which is to come under the hammer on May 24th.

Those in the know are one step ahead; but victory comes to those who know more at an early stage. Working on this assumption, the British secret service had assembled the country's most outstanding analysts in Bletchley Park, people from a wide range of professions, to collaborate on decrypting the enemy's coding machines. While the leaders of the Wehrmacht, apart from a few warning voices, were reassured by the fact that the legendary Enigma cipher machine was said to be unbreakable, the British cryptanalysts, led by the mathematician Alan Turing, had already deciphered its underlying principle in spring 1940 and were able to transform encrypted messages into plain text at the flick of a switch from 1941.

It was only at this juncture that the Wanderer Werke in Chemnitz were commissioned to develop a new, improved machine. Based on input from the cryptologist Fritz Menzer (1908 – 2005), the purely mechanical Schlüsselgerät 41 was now modeled on the fundamental principle developed by the Swedish cryptologist Boris Hagelin (1882 – 1983), albeit with important modifications. The name of the machine derives from the year of its invention. Unlike the Enigma, which used lamps for the letters, it worked with two reels of paper; the encryption process involved turning the drum through 360 degrees with the attached crank handle. This rotated six cipher wheels, rather than the previous three, of differing sizes, in a highly irregular motion, sometimes even backwards. Moreover, the position of one wheel affected the movement of the others. The recipient had to set the wheels in the identical starting position before entering the encrypted text. The plain text and the encrypted message were printed in parallel on two strips of paper. Of the 11,000 devices ordered, only approximately 500 units were shipped to the Abwehr, or military intelligence service, and another 1,000 to the weather service, from October 1944. However, the latter was supplied with the SG-41Z numerical version, with numbers instead of letter keys. Weighing in at 13 kilos, the SG-41 was deemed too heavy for front line use.

Even the experts in England failed to reconstruct – and thus decipher – the SG-41 by the end of the war. Accordingly, the allies described the cipher machine with deference as a "remarkable machine". How many more years World War II would have lasted, had this new encryption technique been deployed earlier, is still widely debated today; although the outcome was probably inevitable.


Serial number 000352, manufacturer's code "cxo" (Wanderer Werke), built in 1944. Identification plate reads "Schl. Ger. 41 / 000352 cxo 44". Blue-green steel case, 26 keys, hinged document support with spring-loaded holder. Folding crank on the right hand side, hence the nickname "Hitler Mill". Crank numbered "21". Extractable carrying handle. Front door to insert two paper reels into a pull-out holder. Two paper reels inserted (might be postwar replacements), one to output the original, one for the encoded message. Removable inked wheel holder to color the paper strip, its cover labelled "1" and "2". Two knurled wheels with 2 positions each, the left one marked "V" and "E", the right one marked "F" and "L". Left hand lever for paper transport, loose. The floor plate slightly dinged with some damage to the original paint and traces of surface rust. Sits on two wooden strips, the right one marked Eagle/HK above "WaA69" (for C. Verberne Berlin/Neukölln 1936, maker of switchboards). The two small rear screws to hold the top cover, and the protective cover of the entire machine missing. Dimensions 27 x 31 x 17 cm (WxDxH), weight 10,8 kg. The device appears to be fully intact and working and is surprisingly well preserved.

In recent years no sample of this ultra rare machine in an anywhere near as good condition has surfaced on the market! Condition: II +

Live auction: May 20-24, 2019
Online auction: June 4-7, 2019

About Hermann Historica

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Hermann Historica GmbH, Munich, is one of the world's leading auction houses in the special areas: antique arms and armors, hunting collectibles, antiquities, orders as well as objects from history and military history. Founded as early as almost 50 years ago by Count Erich Klenau von Klenova, Baron von Janowitz in Nuremberg as an auction house for coins, from the very beginning also orders and decorations as well as objects of military history were put up to auction. In the early seventies the range of the auctions was broadened by the category of “antique arms and armor”. The wide range was soon accepted by international collectors and museums. In 1982 the present owners renamed the auction house Hermann Historica GmbH, and at least two auctions are conducted annually which address more than 40,000 clients worldwide. Particularly sensational are the numerous objects from the possessions of noble houses, notably those of the German and Austrian imperial family, which continue to attract international attention, the auctions dispersing complete collections such as the sale of the hunting treasures of Castle Fuschl in Salzburg, as well as the much-noticed sale of the unique collection Karsten Klingbeil of ”Arms and Armor” and the “Collection of Antique Greek and Roman Arms” of Axel Guttmann, the liquidation of the Nümbrecht Museum of Historical Technology, the worldwide biggest auctions of "Children’s Dreams on Wheels", the pedal cars of the Centre of Extraordinary Museums in Munich.

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