A long time ago, in a developmental & testing facility far, far away...
An engineer was sitting on a mechanic's stool (you know, those little stools on wheels), legs akimbo (as one tends to do on those stools), while closely observing the operation of said switch in a test rig. As he lent back to make a note on the test chart, Newton's law caused his stool to roll much closer to the switch just as it happened to be closing.
The rest is history.
Last edited by Tinstaafl; 12th Oct 2013 at 17:22.