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Show Electricity Does This Little Trick TRICK BY STATIC. CORK S SHADOW X. CAST OKI N this simple experiment you place a rectangle of glass on top of two thin books about three inches apart as shown in the diagram. dia-gram. In the space between the books sprinkle some cork powder made by filing an ordinary cork with a fine file. Rub the surface ! of the glass vigorously with a piece of silk and presto! the cork powder jumps up and sticks to the glass just as iron filings fly to a magnet. This experiment can be turned into a smart magical trick if you first dip your finger in some glycerin glyc-erin (or other sticky substance that will not dry quickly) and outline on the glass a comic face. Now hang a large sheet of white paper on the wall and tell your friends you are going to project a picture on the screen simply by rubbing the glass. Place the glass on the books between which are your cork filings and proceed to rub it with the piece of silk until the cork powder jumps up and sticks to the glass. At this stage of the trick, turn out the lights and hold the magic glass up in front of the screen a few Inches away from it. Then ask someone to light a candle you have In readiness and advance with It slowly towards the glass. When in the right position, the candle will throw on the screen a shadow of the funny face you have drawn on the glass with glycerin. |