........................................................... FIG. 181.—Magnetic Phantom about a Coil of Wire carrying a current. FIG. 182.—Illustrating the Principle of the Induction Wireless Telephone. ........................................................ FIG. 183.—Showing how the Coils may be formed by winding around nails set in a circle in the Floor. ............................... FIG. 184.—Circuit Diagram showing how the Coil is connected so as to serve for either transmitting or receiving. ....................... FIG. 185.—Apparatus for Electrolysis Experiment. .................. FIG. 186.—Electroplating Tank. .................................... FIG. 187.—Generating Electric Current by Heat. .................... FIG. 188.—A Handy Light. .......................................... FIG. 189.—Experimental Arc Lamp. .................................. FIG. 190.—The Magnetic Diver. ..................................... FIG. 191.—The Magnetic Fish. ...................................... FIG. 192.—The Magnetic Clown. ..................................... FIG. 193.—An Electric Breeze. ..................................... FIG. 194.—The Static Motor. ....................................... CHAPTER I. STATIC ELECTRICAL APPARATUS *Static Electricity. How to Build a Wimshurst Machine. Experiments with Static Electrical Apparatus.* *Static Electricity* is an extremely interesting subject for the amateur experimenter, in view of the many spectacular experiments which may be performed with it. The number of such experiments is almost unlimited. Static electricity was the first evidence of the wonderful force which in the present day moves trains, lights our homes, etc., to come to the notice of man. Long before the days of batteries, dynamos, telegraphs, electric lights and before, perhaps, such things were even dreamed of, static electricity absorbed the attention of scientists, and the names of some of the world’s greatest men such as for instance, Aristotle, Roger Bacon, Gilbert, Boyle, Newton, Franklin, etc., are closely linked with its history. It is probably safe to say that experiments with static electricity led the famous Italian, Galvani, to the discovery of the sort of electricity called *galvanic* currents, and to the battery. Galvanic current is the sort of electricity produced by batteries and has the same properties in many ways as that generated by huge dynamos in the power houses of to-day. The modern boy can duplicate these old experiments far more easily and on a larger scale than any of the old scientists could, owing to the fact that he is supplied with explicit directions and can easily obtain the necessary materials at a neighboring hardware or electrical store, whereas men like Newton and Franklin not only had to *devise* or *invent* their own apparatus but make their materials as well. How to Build a Wimshurst Machine.