The Snail Ball - a small, metallic gold coloured ball just over 2cm in diameter. Place it on the sloping plastic channel and you would expect it to roll down in the normal way. Well, this ball does roll, but it does so incredibly slowly. To an audience, it seems baffling why it should roll down a slope apparently in slow motion. You can pick the ball up, and it seems quite heavy. No clues if you shake it.
However inside the ball, which is actually hollow, there is a viscous liquid and a smaller solid ball which is very heavy. When the Snail Ball rolls slowly down an incline, it is the smaller, heavier ball inside that determines the pace, and this is slow because of the viscous liquid. Obviously the slope cannot be too extreme, or the ball will simply slide down it and the 'snail' action will cease to work. Either way, a beautiful product made by a master craftsman in Germany. The Snail Ball is supplied in a small leather pouch, together with the plastic sloping ramp.
Made in EU
In October 2010, Stan Wagon from Macalester College, Minnesota, wrote an article about the Snail Ball for Mathematics Magazine, which is published by the Mathematical Association of America. You can read the article here.