limited vision, surveys this vast accumulation of tools, instruments and machinery, and sees what has been and is now beingp. 9 accomplished, it is not to be wondered at that he should enter the field with timidity. In his mind the great question is, how to acquire the knowledge. There is so much to learn. How can it be accomplished?

The answer to this is, that the student of to-day has the advantage of the knowledge of all who have gone before; and now the pertinent thing is to acquire that knowledge.

The Means Employed.—This brings us definitely down to an examination of the means that we shall employ to instil this knowledge, so that it may become a permanent asset to the student's store of information.

The most significant thing in the history of electrical development is the knowledge that of all the great scientists not one of them ever added any knowledge to the science on purely speculative reasoning. All of them were experimenters. They practically applied and developed their theories in the laboratory or the workshop. The natural inference is, therefore, that the boy who starts out to acquire a knowledge of electricity, must not only theorize, but that he shall, primarily, conduct the experiments, and thereby acquire the information in a practical way, one example of which will make a more lasting impression than pages of dry text

p. 10

Throughout these pages, therefore, I shall, as briefly as possible, point out the theories involved, as a foundation for the work, and then illustrate the structural types or samples; and the work is so arranged that what is done to-day is merely a prelude or stepping-stone to the next phase of the art. In reality, we shall travel, to a considerable extent, the course which the great investigators followed when they were groping for the facts and discovering the great manifestations in nature.

p. 11

CHAPTER IIToC

WHAT TOOLS AND APPARATUS ARE NEEDED

Preparing the Workshop.—Before commencing actual experiments we should prepare the workshop and tools. Since we are going into this work as pioneers, we shall have to be dependent upon our own efforts for the production of the electrical apparatus, so as to be able, with our home-made factory, to provide the power, the heat and the electricity. Then, finding we are successful in these enterprises, we may look forward for "more worlds to conquer."

By this time our neighbors will become interested in and solicit work from us.

Uses of Our Workshops.—They may want us to test batteries, and it then becomes necessary to construct mechanism to detect and measure electricity; to install new and improved apparatus; and to put in and connect up electric bells in their houses, as well as burglar alarms. To meet the requirements, we put in a telegraph line, having learned, as well as we are able, how they are made and operated. But we find the telegraph too slow and altogether unsuited for our purposes, as well as for the uses of the neighborhood,p. 12 so we conclude to put in a telephone system.

What to Build.—It is necessary, therefore, to commence right at the bottom to build a telephone, a transmitter, a receiver and a switch-board for our system. From the telephone we soon see the desirability of getting into touch with the great outside world, and wireless telegraphy absorbs our time and energies.

But as we learn more and more of the wonderful things electricity will do, we are brought into contact with problems which directly interest the home. Sanitation attracts our attention. Why cannot electricity act as an agent to purify our drinking water, to sterilize sewage and to arrest offensive odors? We must, therefore, learn something about the subject of electrolysis.

What to Learn.—The decomposition of water is not the only thing that we shall describe pertaining to this subject. We go a step further, and find that we can decompose metals as well as liquids, and that we can make a pure metal out of an impure one, as well as make the foulest water pure. But we shall also, in the course of our experiments, find that a cheap metal can be coated with a costly one by means of electricity—that we can electroplate by electrolysis.

Uses of the Electrical Devices.—While allp. 13 this is progressing and our factory is turning out an amazing variety of useful articles, we are led to inquire into the uses to which we may devote our surplus electricity. The current may be diverted for boiling water; for welding metals; for heating sad-irons, as well as for other purposes which are daily required.

Tools.—To do these things tools are necessary, and for the present they should not be expensive. A small, rigidly built bench is the first requirement. This may be made, as shown in Fig. 1, of three 2-inch planks, each 10 inches wide and 6 feet long, mounted on legs 36 inches in height. In the front part are three drawers for your material, or the small odds and ends, as well as for such little tools as you may accumulate. Then you will need a small vise, say, with a 2-inch jaw, and you will also require a hand reel for winding magnets. This will be fully described hereafter.

You can also, probably, get a small, cheap anvil, which will be of the greatest service in your work. It should be mounted close up to the work bench. Two small hammers, one with an A-shaped peon, and the other with a round peon, should be selected, and also a plane and a small wood saw with fine teeth. A bit stock, or a ratchet drill, if you can afford it, with a variety of small drills; two wood chisels, say of ⅜-inch and ¾-inch widths;p. 14 small cold chisels; hack saw, 10-inch blade; small iron square; pair of dividers; tin shears; wire cutters; 2 pairs of pliers, one flat and the other round-nosed; 2 awls, centering punch, wire cutters, and, finally, soldering tools.