Canadian software developer Matthias Wandel enjoys spending his spare time creating wooden contraptions that combine a childlike sense of wonder with an engineer’s knowledge of mechanics. One of his most popular creations so far is this six-bit binary adding machine, which has tallied nearly one and a half million views on YouTube. As Rick Regan explains at Exploring Binary, the machine functions like a low-tech integrated circuit. “It uses wood instead of silicon, gravity instead of voltage, and marbles instead of current,” he writes. “We don’t need no stinkin’ CMOS!”
The idea came to Wandel after he noticed that one of his earlier marble machines incorporated logic-like elements. “It had occurred to me,” he writes on his woodworking site, “that perhaps with an insane amount of perseverance, it might be possible to build a whole computer that runs on marbles.” To illustrate the point Wandel built the adding machine, which stores the binary states of six bits and can add numbers from one to 63. The result may be more cool than practical, writes Regan, “but it certainly is educational. It illustrates basic principles of binary numbers, binary arithmetic, and binary logic.”
You can learn more about the machine on Wandel’s Web page, and about the underlying logic and mathematics at Exploring Binary.