# Mechanical Pi - In memory of William Shanks

The mathematician William Shanks sacrificed years of his spare time to the decimal expansion of the irrational number pi by hand. In 1873 he published his handwritten calculations to the 707th digit. Much to his regret, in 1945, D.F. Ferguson proved that only the first 527 decimal places have been calculated correctly. Nowadays Shanks tedious manual task is done with the help of computer algebra, performing millions of steps in fragments of a second, while calculating billions of decimal places. Mechanical PI is a computing machine replacing this repetitive algorithm back into a physical, mechanical language. A constant rotation, pressing and repeating the calculator’s keys, approaching the number Pi, yet never reaching it...

The machine utilizes the Leibniz formula for pi which is an infinite series of additions and subtractions of quotients. Each subsequent denominator in this series is the sum of the previous one plus two, starting with the value one. With this being the only variable expression and the possibility to store values in the calculators memory, the formula can be expressed as a repetitive keystroke combination activated by circular motion. images: flickr.com/photos/126414840@N08/sets/72157646313007809/ Florian Born - florianborn.com David Friedrich - durchnull.de Digitale Klasse - University of the Arts Berlin 2014

Prof. Joachim Sauter, Prof. Jussi Ängeslevä

- Kind: Short
- Year: 2014
- Runtime: 1 min
- By: Florian Born
- Genres: Science
- Archive: [Wikimedia Commons](https://commons.wikimedia.org/wiki/File:Mechanical_Pi_-_In_memory_of_William_Shanks.webm)
- Licence or status: [CC BY 3.0](https://creativecommons.org/licenses/by/3.0) (as the archive states it)
- Credit: Florian Born
- Who can watch: Tweens profiles and older (the archive gives no rating; placed by Invisible Network from its collection and subjects)

[Watch now](https://invisiblenetwork.ai/watch/archive/commons/85092863?play=1)