A bowl is filled with rice and an empty bowl is placed upside down atop it, making a kind of funky sphere. The top bowl is removed and rice overflows -- the grain obviously having doubled by some mysterious force. The rice is the bottom bowl is leveled and the top bowl is replaced.
The top bowl is removed again, and this time the bottom bowl is shown to be full of water. The rice is gone!
This effect is largely mechanical, relying as it does on the properties of normal, store-bought Chinese rice.
Before performing the effect, the magician fills one bowl with water. The other bowl is filled with rice.
On stage, the magician turns the water bowl upside down over the rice bowl -- doing so quickly so that water doesn't fly everywhere, potentially disrupting the illusion. A moment of magical patter is enough to let the water soak into the rice, which will immediately begin to expand.
When the top bowl is removed, the expanded rice will spill out of the bottom bowl. This rice is scraped away, and because Chinese rice tends to clump together, all of the rice will be pulled out of the bowl, leaving behind that water which has not already been absorbed. Left with a bowl filled with nothing but water, showmanship is all that is needed to finish the effect.
After the effect is complete, the magician should gather up the rice and store it in a sanitary, covered plastic container. After a number of performances, the accumulated rice can be prepared as a nutritious meal for the magician. (This explains why the effect is quite popular with street magicians working in areas where business is shaky.)