Swiss NEMA Cipher Machine

This Swiss-engineered cipher machine is a fascinating piece of 20th-century military and engineering history, and this particular example is one of the few rare models intended as a war machine. Called the NEMA, short for the Neue Machine, or “New Machine,” it was developed by Zellweger AG, along with a team of mathematicians in Uster, Switzerland during World War II. The Swiss Army was in need of a replacement for their previous machine, the German-made “Kommerziell” or “Enigma K,” after discovering that it had been de-coded by both Allied and the German cryptanalysts.

The wheel-based NEMA is visually similar to the German Enigma, but it is more complex. It consists of ten wheels, five of which are electrically wired (four coding wheels and one reflector wheel). The reflector wheel can be moved during encryption, unlike the reflector on the Enigma model, which allowed designers to effectively replace the plug board found on the Enigma. Each of these five coding wheels is paired with a “stepping” or "drive" wheel which sets the stepping motion of each wheel, meaning that each cipher wheel has a unique stepping motion. This is unique from the Enigma’s "odometer" style stepping motion, allowing the NEMA to be more irregular and more difficult to break.

Developed between 1941 and 1943 by a team of Swiss mathematics professors led by Captain Arthur Alder at the University of Bern, the prototype was completed in 1944. After modifications in 1945, the final versions were created by Zellweger AG and released for service in 1947. Though too late to be utilized during World War II, the NEMA became widely used by the Swiss Army and the Diplomatic Corps during the Cold War era.

Only 640 of these machines are believed to have been created by Zellweger AG. This particular model was one of the rare war machines that were kept in reserve storage to be used in the event of war, and these so-called “Operational Machines” are extraordinarily rare. These models were slightly different from their non-war machine counterparts, with different notches on the stepping wheels and two extra wheels stored in the lid. The case also features the following label:Nur bei Kriegsmobilmachung abgeben! Ne délivrer qu'en cas de mobilisation de guerre! Da consegn. solo in caso di mobilitazione di guerra !, meaning “Issue only in case of war mobilization” in three languages, German, French and Italian.

The NEMA machine bears its original plaques and it is marked with its serial number TD-688. It also comes complete with its original operating manual.

Circa 1946

12 3/4“ wide x 14 3/8“ deep x 5 3/4” high