Mechanical computers

From: Len Shustek <>
Date: Thu Jan 14 22:30:25 1999

At 05:17 PM 1/13/99 -0800, Uncle Roger wrote:
>At 12:57 AM 1/13/99 -0600, you wrote:
>>>Gag? Mechanical computers are serious stuff, Hans. Like Danny Hillis'
>>>tinker-toy tic-tic-toe machine:

Which is, incidentally, still on display at The Computer Museum
in Boston. It hasn't been run for a while, though, so it probably
would need considerable tuning to work.

If the subject is mechanical computers in general, one of the most
prolific inventors thereof was Prof. Derrick Lehmer (1905-1991)
who was on the faculty at UC Berkeley for about 50 years. His
hobby was devising different kinds of mechanical sieve computers
to solve linear congruence problems like finding primes.

At The Computer Museum History Center at Moffet Field in Mountain
View CA (the historical spin-off of the Boston museum) we have at
least four of his sieve computers, made of principal components
as follows:

  1. Cardboard sheets with holes, operated by knitting needles
  2. Bicycle chains of various lengths with screw stops
  3. Heavy toothed gears, toothpicks, and a car headlight
  4. 35mm film and wooden mallets

The guy was a regular Rube Goldberg, but they all worked!

-- Len Shustek
Received on Thu Jan 14 1999 - 22:30:25 GMT

This archive was generated by hypermail 2.3.0 : Fri Oct 10 2014 - 23:32:06 BST