Smart Putty

'Silly putty' or 'bouncy putty' has long been available as an amusement. Properly known as visco-elastic polymer or dilatent compound. This class of material has the remarkable property that it usually behaves as a soft mouldable plastic (like chewing gum), but instantly becomes a rubber if impacted: i.e. it bounces like a ball. The gum version of the putty flows more readily and can be used, for example, as a clock. A ball bearing (or similar) will descend slowly through a tube of clear gum at a uniform rate.) Supplied in 25g containers.