Simple Simon, world's smallest mechanical brain, visits Seattle on June 20, 1950.

  • By David Wilma
  • Posted 3/22/2000
  • HistoryLink.org Essay 2490
See Additional Media

On June 20, 1950, Simple Simon, the world's smallest "mechanical brain" visits Seattle as part of the American Society of Engineering Education convention at the University of Washington. Weighing 39 pounds and measuring 24 inches long, 15 inches wide, and 6 inches tall, Simple Simon is more "feeble minded" than its larger relatives. Simple Simon can use four digits and can hold 16 numbers at a time. It cost $540 to build this ancestor of today's computers.

Dr. Ned L. Reglein transported the device from Harvard University to demonstrate "giant computers" which can handle 5,000 problems a second involving figures up to 351,000,000 digits.

Wrestling With Addition

The Seattle Times described Simon in action:

"Here's how it works: Reglein feeds a perforated tape containing a mathematical problem into Simon's "mouth."

The problem today was to first add 2 and 1, then find the negative of 3, which is 1. Next, find which of these two results is the greater. (1.) After that, select "2" if the first result is greater than the second. (2.) Simple, what?"

In went the tape. Simon's life blood, 24 volts of A.C. current, flooded through his insulated veins. The brain's mechanism made a ratchety sound as it wrestled with the addition of "2 and 1." Finally, Simon blinked his lights to indicate "3" and relief swept over Dr. Reglein's features.

"Right!" he shouted exultantly.


Sources:

The Seattle Times, June 20, 1950, p. 8.


Licensing: This essay is licensed under a Creative Commons license that encourages reproduction with attribution. Credit should be given to both HistoryLink.org and to the author, and sources must be included with any reproduction. Click the icon for more info. Please note that this Creative Commons license applies to text only, and not to images. For more information regarding individual photos or images, please contact the source noted in the image credit.
This work is licensed under a Creative Commons Attribution-NonCommercial-NoDerivs 3.0 Unported License
Major Support for HistoryLink.org Provided By: The State of Washington | Patsy Bullitt Collins | Paul G. Allen Family Foundation | Museum Of History & Industry | 4Culture (King County Lodging Tax Revenue) | City of Seattle | City of Bellevue | City of Tacoma | King County | The Peach Foundation | Microsoft Corporation, Other Public and Private Sponsors and Visitors Like You