h2g2 The Hitchhiker's Guide to the Galaxy: Earth Edition

If there is one thing that amazes people (at least for five seconds anyway) it's when they see they see a drawing pin being spun like a spinning top for the first time.

It's pretty tricky to master but the principle is much the same as a spinning top - spin the drawing pin as fast as possible and it will balance on it's pin thanks to the gyroscopic effect caused by the disc rotating.

The preferred technique is this - take a drawing pin, preferably one with a large "disc" and where the pin is perfectly centered and perpendicular to it (i.e. not bent sideways); place the pin between forefinger and thumb with the pointy end downwards; rapidly move finger and thumb in a "finger-click" style motion to give the pin some spin and simultaneously release it over a flat surface.

If you get it right the pin will land on the surface and will spin for a good 30 seconds or more before losing momentum. If you louse it up it'll probably skitter off the surface and you'll have to try again.

With practice it's even possible to spin map pins (the ones with a little plastic ball instead of a disc) but they don't spin nearly as long. Real experts can even spin pins on the palm of their hands.

Something even more unbelievably cool (and vaguely gyroscopic) to do with map pins (I'm not sure if it works with drawing pins) is to put them in a glass of lemonade. It works better if the lemonade is quite flat. The rough surface encourages formation of bubbles on the surface of the pin head. What tends to happen is the pin rises up onto its point and spins madly as bubbles form and float it up.

Try it!

H.