Polyox (polyethylene oxide) is a non-toxic, long-chain polymer with a high molar mass. Because of extensive hydrogen bonding, it is soluble in water. A solution of Polyox (approximately 1% w/v) behaves as an 'elastic liquid' i.e. it 'self-siphons'. If you quickly drag some of the solution from a beaker with a spatula or spoon, it will continue to move out of the beaker. You can even draw it up into a syringe even though the tip of the syringe is above the liquid level. 5g is sufficient to make about 500cm3 of the fluid. Please note: Propan–2–ol is required for use with this item but should be available at most schools. Use of a magnetic stirrer is recommended.