A Colossal Secret

Ian Evenden discovers how British WWII braniacs, faced with an impossible task, helped save millions of lives and invented the computer as we know it

- Por Ian Evenden

Your country is at war, and you start picking up directional radio signals that sound like nothing you’ve ever heard before. The enemy is highly mechanized, makes use of the latest technology, and has a record of using complex codes and ciphers in its transmissions. This is something new, however. Instead of the dots and dashes of the Morse code you’re used to intercepting, this sounds like a harsh wailing.

These days, we’d probably equate the sound with a 56K modem, but back in the 1940s, it was known as teleprinter code. Nazi high command, not content with the “unbreakable” Enigma cipher it used to spread orders among its companies and brigades, was also using a machine for higher-level communications called the Lorenz SZ that British codebreakers had never seen, and would not see until the end of World War II. Despite this, they were able to deduce how it worked, and crack the encipherment.

This is the story of a country house in England full of mathematicians, crossword enthusiasts, the occasional genius, and a man from the postal service more used to creating automated telephone exchanges. Together, they read German military communications and shortened WWII by up to four years, saved possibly millions of lives, and created Colossus, the first programmable electronic computer, in the process.