[Leica] OT:Type 240

[Herbert Kanner]

I always wonder where these numbers come from. Examples” some early mainframe computers: IBM’s first scientific computer: 701, IBM’s most successful business data computer: 1401, major Control Data computer: 3600. Well, I learned the story of one of these when doing essential reading after becoming a docent in the Computer History Museum.

During WWII, the U.S. Navy had a group of engineering officers developing specialized hardware to aid in cryptography. When the war ended, the Navy wanted to keep these guys, so it persuaded them to form a corporation (Engineering Research Associates, or ERA for short, and bought them a building in Minneapolis that used to be a glider factory. The Navy gave these guys thirteen consecutive tasks, the thirteenth being to build a general-purpose computer.

The computer was so successful that ERA asked the Navy for permission to sell this computer commercially after first removing a secret instruction code from the public version. It was granted. I actually saw this computer in operation around 1951 at George Washington University. It was sold as the ERA 1101.

What I learned at the Museum was that 1101 was very appropriate; as a binary number, its value is thirteen.


Herbert Kanner
kanner at acm.org
650-326-8204

Question authority and the authorities will question you.