Walter and the Wireless

by Sara Ware Bassett

Therefore the initial lesson began gayly.

At first Bob, seated in the chair of state facing his class, was shy and embarrassed; but soon he forgot himself in his subject and losing his hesitancy he spoke with the authority of one who has mastered his art.

"I am going to begin," said he, "just as they began with me at the radio station for I think if you get the principles of wireless at the outset you will find it much easier to understand it. And to do this we shall not start with wires, generators, detectors, or anything of that sort; instead we must go back of them all to the earth and the air, and learn how it is possible for sound to travel without the aid of human devices. For in reality there is something that takes the place of man-made wires. This is the ether. Surrounding the earth moves the air we breathe; and as we go higher this air becomes thinner and thinner until, by and by, a height is reached where the air gives place to ether, a sort of radiant energy that bridges the zone between the air space that encircles the earth and the sun, and brings to us its heat. This great sea of ether is made up of particles that are never still and which are so small that they get between every substance they encounter, thereby becoming a universal medium for transmitting light, heat, color and many other things to our earth. Without this body of ether, there would be no agency to pass on to us (as well as to the many other planets of our solar system and those outside it) the energy the sun generates, which is the thing that keeps us alive."

Bob waited a moment to make sure that his point was clear and then proceeded:

"Now this energy as it moves through the ether takes the form of waves; and these waves go out not in a single train but since the ether is continually disturbed by the sun, in series of wave trains that vary in frequency. Such waves are electromagnetic in character, and light, heat, sound, and the waves carrying wireless messages are all of a similar type, differing only in their relative rates of vibration. If unobstructed, and moving through free ether, all of them travel at practically the same velocity, that is about one hundred eighty-six thousand miles a second. When, however, they encounter other substances, as they are continually bound to do, this rate of velocity changes. The waves of sound, for example, sent out by the wireless telephone are very slow compared with the high-rate vibrations that produce waves resulting in light."

Again the youthful teacher paused.

"Now this constant turmoil in the ether which creates the magnetic area explains why the magnetized needle of a compass unfailingly points north and south. This one simple fact is a certain proof of its existence. And once granting a magnetic field to be there it is less difficult to understand how wireless waves are produced in this congenial medium and find their way through it, following in their journey the curve of the earth's surface."

Bob smiled at his audience encouragingly.

"If you can once get this wave law through your heads the rest is not hard," asserted he, "for the whole wireless system is based on wave motion."

"With an ocean spread out before us we ought to be able to understand waves," interpolated Nancy.