The Newtonian Glow Putty is a great way to see the difference between Newtonian and non-Newtonian fluid ? as well as being lots of fun to play with! This non Newtonian fluid behaves as a viscous liquid with slow movements ? it stretches and puddles - but as an elastic solid with quick movements ? it bounces and snaps. The Glow Putty also illuminates in the dark.