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How to do the Tricks

What Color Is Blue Ink?

Ask this question of your audience. Then proceed to show them that blue ink is not "blue." It is a mixture of several colors. Pour about 25 mL of water and 25 mL of alcohol in a small plastic glass. Cut 4 or 5 strips of filter paper about 4 cm wide and 15 cm long. Fold the strips in half lengthwise. Using an eyedropper, place a drop of blue ink about 5 cm from the end of each paper strip.

Place the strips in the glass so that the ends of the paper are just below the surface of the liquid. Tape the strips to the glass to hold them in place. After about 20 minutes, remove the strips and have the audience examine them. Ask again: "What color is blue ink?"

The Invisible Force

Tell your audience that you will overturn a full glass of water and use an "invisible force" to keep the water in the glass. Carefully fill a glass to the brim with water. Place an index card on top of the glass so that the card completely covers the mouth of the glass. Be careful not to spill any water. While holding the index card firmly in place, quickly turn the glass upside down.

Slowly and carefully remove your hand from the index card. Some invisible force will hold the card in place.

The Leakproof Strainer

Strainers have holes that allow water and other liquids to flow through. You can make a mysterious strainer that holds water. Show your audience what happens when you pour a little water into the strainer. Next, without allowing your audience to see what you’re doing, pour a little cooking oil into the strainer and swirl it around to coat the wire mesh. Gently shake the strainer so that the holes open. Then hold the strainer up and announce that it will now hold water. Pour water into the strainer to prove it.

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