The 73 scientific experiments described in this book can easily be done by children on their own, without the supervision of a parent or teacher. Explicit directions are given for each step, and the only equipment required can be found around the house. By working with such simple materials as steel wool, cotton, candles, eye-dropper, compass, cork, rubber tubing, coins and magnets, the young experimenter will become acquainted with dozens of the basic principles of physics, chemistry, mechanics, engineering, and many other fields. Following the step-by-step instructions, a child can learn to make an air-screw, mariner's compass, simple siphon, pinhole camera, thermometer, invisible ink, simple electric motor, periscope, boomerang, 3-D viewer, and many other interesting things. The exercises and demonstrations also show how to burn steel, find a center of gravity, make a vacuum with a radish, electrify a bubble, reflect sound, make water denser, compress air under water, carry a column of water, make a liquid sandwich, watch a pulse at work, etc. Each article gives some background information along with an explanation of why the experiment works the way it does. Over 100 photographs show children performing the experiments, and numerous line drawings depict the materials used, the set-up of equipment, and the desired result.