Archeologists have found day tables from 1500 BCE that were written in code, and the Romans used a code called the Caesar cipher. But until the Enigma machine, codes and ciphers had to be written and decoded by hand. The Enigma machine was battery powered and could accomplish the same job in 2 or 3 minutes. Plus it could create 22 billion different code combinations. The Enigma machine looked like a typewriter with rotating wheels. The keys were connected through intricate wiring to those wheels. As soon as the Enigma machine reached London, a team of mathematicians and scientists set up a laboratory in an old mansion in the small town of Bletchley Park. These scientists worked frantically to figure out a way to build a machine that could match the electrical circuits of the Enigma machine. The machine they built, called Bombe, could match the circuitry of Enigma.