Present an empty cage and two vacant brass cylinders (tubes). Slap one cylinder over the cage, then the other, making a big show of their emptiness (as if they’re not just waiting to surprise someone). Lift them off and – BAM! The cage's playing host to a bunch of vibrant balls! Audiences will be scratching their heads and chuckling; it’s a classic for a reason! (Trust me, they’ll love it!)
