From 1938 more complexity was added to the Enigma machines, making decryption more difficult. Later, they designed mechanical devices for breaking Enigma cyphers. It has since been turned over an archaeology museum in Schleswig. German military messages done on the Enigma machine were first broken by the Polish Cipher Bureau, beginning in December 1932.
The museum said it has also scanned the lesser-known Key Device 41 (SG-41), which is a mechanical key machine that looks a bit like a typewriter and was used toward the end of World War II by small numbers of people working for Germany’s intelligence services. The Enigma machine the divers discovered had three rotors, which means it was used on warships, not German U-boats. British cryptologists led by Alan Turing deciphered many German messages during the war, and information they gathered after “cracking the code” gave the Allied war effort a significant boost against the Third Reich, historians have said. The sophisticated Enigma machine was improved under Adolf Hitler’s Nazi regime in World War II in a bid to encrypt sensitive military communications. (Deutsches Museum, Konrad Rainer/Zenger) Though it is one of the best studied examples, specialized X-ray technology can still provide deeper insights into the Enigma machine. “Some encryption devices are welded or even filled with a mysterious substance that ensures that the inner workings of the machine are destroyed when the housing is opened.” An Enigma machine from the Deutsches Museum collection. “The Enigma has been researched quite well, but other encryption devices simply cannot be opened without being destroyed,” Dahlke said.