Super Ball & Tube

The magician displays some elegant objects: a brass tube and a solid steel sphere. He places the sphere on the tube, whose inner surface is smaller than the sphere's diameter. After a moment of suspense, the sphere magically sinks into the tube... and then pops back out! The magician then hands the objects to a spectator to try the magic, but they will fail!

• The tube is 3.5 cm high and has a diameter of 1.8 cm.
• Easy to make, pocket-sized (to carry with you at all times) and impressive for any audience.
• At the end, everything can be handed out to the audience for inspection.