One of those really baffling effects! Show two empty bowls. Pour rice into the bottom bowl, then place the other bowl on top. When you remove the top one, the bottom one is filled with more rice than could possibly be contained by the two bowls! Cover the bowls, then uncover them- the rice has vanished- and changed to water! Classic trick that is still very popular! And beware cheap imitations- these are the GOOD ones!