The center of the magnifying glass should be even with the middle of the paper. Stand up the card approximately six inches in front of the magnifying glass, using another lump of clay. Shine a bright flashlight through the cutout toward the fishbowl. You should see a bright image appear on the tissue paper at the back of the fishbowl. It should appear upside down.
Students can estimate which fingerprint type most frequently occurs by sampling their class.
Have them begin by taking their fingerprints. Instruct each student to rub a pencil hard on a small piece of paper, and then to rub one thumb into the pencil mark on the paper. Divide students into pairs. By turns, have each student apply a small piece of cellophane tape over the partner's thumb, being careful not to let it slide. Have the partner then carefully lift up the tape and transfer it to a clean piece of paper.