Drape the handkerchief over the glass, making sure that you push the center of the handkerchief down into the glass.
Fill the glass 3/4 full with water by pouring water into the middle of the handkerchief.
Slowly pull the handkerchief down the sides of the glass making it taut (stretched tightly across the surface of the glass). Grip the ends of the handkerchief at the bottom of the glass.
Place one hand over the mouth of the glass and turn it over with the other hand.
Pull the lower hand away from the glass (slowly) and the water should stay in the glass! This just goes to prove that the handkerchief has anti-gravity properties. The thunderous applause will drown out the cries of, 'How did you do that?'
For the big finish, put your hand over the mouth of the glass and turn the glass right-side up. Remove the handkerchief fromthe glass and pour the water back into the pitcher. Of course, take your well-deserved bow.

How does it work?

Most people predict that the water will leak through the holes in the handkerchief because the water leaked through the holes as it was poured into the glass. The holes in the handkerchief literally disappeared when the cloth was stretched tightly across the mouth of the glass. This action allowed the water molecules to bond to other water molecules, creating what is called surface tension. The water stays in the glass even though there are tiny holes in the handkerchief because the molecules of water are joined together to form a thin membrane between each opening in the cloth. Be careful not to tip the glass too much because you'll break the surface tension and surprise everyone with a gush of water!
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