Divers searching the Baltic Sea for discarded fishing nets have stumbled upon the rarest find: an Enigma encryption machine used by the Nazis to encode secret messages during World War II.
The electromechanical device was used extensively by the Nazi military to encrypt communications, which were typically transmitted by radio in Morse code. Three or more rotors on the device used a stream cipher to convert each letter of the alphabet into another letter.
The Enigma had the appearance of a typewriter. An operator would use the keys to type plain text, and the converted ciphertext would be reflected in 26 lights above the keys – one light for each converted letter. The converted letters would then be transcribed to derive the ciphertext.
Cipher keys were changed using a series of device settings that were changed regularly using pre-available lists. People who received the messages had to use the same lists as the senders to make the messages readable.
Divers commissioned by the environmental organization WWF found the Enigma machine last month while searching for abandoned fishing nets in Gelting Bay off the coast of Germany. As the image above shows, the recovered device was rusty and corroded, but individual keys with the letters they denoted remain intact and clearly visible.
“A colleague swam up and said, ‘There’s a net there with an old typewriter in it,'” Florian Huber, the lead diver, told the DPA news agency. The team quickly realized that the device was much more remarkable.
“I have made many exciting and strange discoveries over the past 20 years. But I never dreamed that one day we would find one of the legendary Enigma machines,” Huber told Reuters.
The diver said he believes the device was lost shortly before Germany’s capitulation in May 1945. At the time, Nazi leaders ordered submarines to be sunk in Gelting Bay to prevent them from being captured by the Allies .
The Enigma made it difficult for the Allies to track German submarines until a British team led by mathematician and scientist Alan Turing broke the encryption of the device used. The achievement, which built on breakthroughs made by scientists at Poland’s Cipher Bureau, enabled the Allies to decipher messages about German military movements. Many historians credit the achievement with shortening the war and preventing many thousands of deaths.
Experts from the National Archaeological Museum will restore the machine. The process, which includes extensive desalination, is expected to take about a year.
Post updated to add details about the Polish Cipher Bureau.