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CHAPTER XI
HOW WE REPRODUCE SPEECH

THE SCRIBE'S NOTE ON CHAPTER ELEVEN

In the first part of this chapter the electron explains the part it plays in ordinary telephony.

The reader will picture the transmitting instrument at the one end of the line influencing the receiving instrument at the distant end.

Towards the end of the chapter the electron turns its attention to the newer subject of wireless telephony, which has been accomplished now over a distance of several hundred miles.

My scribe suggested a rather clumsy title for this chapter – "Electrons versus atoms as carriers of speech." I expect he made this suggestion without much thought, for there are two serious objections to such a title.

In the first place, we are not carriers of speech. We are controlled by speech at one end of the telephone line, and we make a reproduction of the speech at the distant end of the line. No sound passes between the two places; there is only a movement of electrons along the connecting line.

My second objection to the hurriedly suggested title is that it is hardly fair to make any comparison between the achievements of atoms of matter and those of ourselves. We are not in the same category as atoms. Besides, we electrons are dependent entirely upon the material atoms for making our work useful to man. For instance, we might keep on making waves in the æther for all time, and yet if the atoms of matter were to pay no heed to those imperceptible waves, man would never be aware of their presence. Indeed we electrons act solely as go-betweens. On the other hand, it is only fair to ourselves to point out that a group of atoms in one town could never communicate with a group of atoms in a distant town unless we electrons came to their aid. It is true that over a very short distance the atoms may communicate directly. For instance, if a heavy blow is given to a large gong, the atoms of metal may vibrate so energetically that they succeed in disturbing the atoms of gas of the surrounding atmosphere for some considerable distance. But in the case of speech, the speaker cannot supply any great energy, so that he can disturb the atmosphere only to a very limited distance. We electrons, however, can do yeoman service in this respect. We have enabled men to speak to one another over immense distances.

The whole affair is very simple. Man speaks and causes the atmospheric atoms to vibrate and impinge upon a light disc or diaphragm in a simple instrument which man has named the telephone. This vibrating disc presses upon a myriad of carbon particles contained in a small case or box, the disc forming one side of the box. When these carbon particles are pressed together we electrons can get across more easily from atom to atom. There is a battery urging us forward, but our motion is dependent entirely upon the manner in which the vibrating disc presses upon the carbon particles. I cannot describe our movement in the line-wire as a march; it is in reality a surging to and fro.

You will understand that this to-and-fro motion of the electrons in the line-wire varies according to the vibrations of the sending disc, which is controlled by the speaker's voice. At the distant end of the line we electrons bring our magnetic powers into action. We keep varying the attractive powers of an electro-magnet, according to the motion of the electrons in the wire. This ever-changing magnet produces vibrations in an iron disc which is fixed close to the magnet. This disc is set vibrating in exact sympathy with the sending disc. When the listener places this receiving disc close to his ear, the vibrations are carried by the atmospheric atoms to his hearing apparatus. All that we electrons have done is to cause one disc to vibrate in exact synchrony with another distant disc. But that is all that is required, for the receiving disc will reproduce similar air-vibrations to those set up by the man's voice at the distant place. I have pointed out already that we do not attempt to carry the sound. It is true that the atoms of matter do the hard work, but it is we electrons who enable a group of atoms in one town to communicate with a group of atoms in a distant town.

It was natural that as soon as man found that he could work his telegraph instruments without the aid of connecting wires, he should try to do the same with his telephone instruments. We were sorry when we found men trying to use the original spark-telegraphy methods for telephones. While we had no difficulty in operating a telegraph instrument by means of æther waves and the tube of filings, it was quite impossible for us to produce telephone vibrations on the same principle. This spark method was a too rough-and-ready plan. The waves we produced were like sudden splashes in the æther ocean, whereas we knew that we must produce regular trains of continuous waves in order to reproduce telephone vibrations. However, you may be aware that we have succeeded by a different arrangement of apparatus. Indeed it may interest you to know that one of my most recent experiences has been in connection with some wireless-telephone experiments.

Unfortunately I was not in a very favourable position to learn all that was going on, but it was quite exciting work. I happened to be attached to an atom of copper in a length of wire which had been run up into the air on a sort of flag-pole arrangement. I need hardly say that I was not alone, for by this time you will have become accustomed to picture myriads of electrons occupying a very small space.

We were set vibrating to and fro with tremendous energy, but what bothered me most was the great variation in our movements. It was the nature of these variations which gave me the clue that we were being controlled by the vibrations of a telephone disc. I can tell you we did make a complex series of waves in the surrounding æther! These waves went out through space and influenced some electrons stationed at a great distance. When these electrons at the receiving station were set in motion they controlled the electric current from a local battery which set a second telephone disc vibrating in synchrony with the one at the sending station.

On questioning some of my fellow-electrons who happened to have been nearer the transmitting part of the instrument than I had been, I got some interesting information. They tell me that there was a dynamo and an arc lamp in our circuit, while the telephone instrument was in a neighbouring circuit. The electrons surging to and fro in the telephone circuit influenced those energetic electrons in the arc-lamp circuit to which the ærial wire was attached. You see that my position in the ærial wire was not a very advantageous one for observing what was taking place.

This was truly a great achievement – to enable one man to speak to another distant hundreds of miles, and without the aid of any connecting wire. I think you will agree with me that we have excelled all past records in the world of wonders.

CHAPTER XII
OUR HEAVIEST DUTIES

THE SCRIBE'S NOTE ON CHAPTER TWELVE

Here the electron explains its behaviour in a dynamo at work.

The principle of the dynamo was discovered by Faraday in the thirties of last century.

He found that when a coil of wire was moved through a magnetic field, there was a current of electricity induced in the moving coil.

Experimental machines were constructed, and after a while a practical dynamo was evolved.

Wires are attached to a dynamo and the electric current is led out.

This current may be conducted to a distant tramway car, and, by sending the current through an electric motor, mechanical motion is produced and the car propelled along.

An electric motor is practically the same as a dynamo, but instead of turning its coil round in order to produce an electric current, we pass a current into the coil and it moves round. It will be sufficient to leave the electron to tell its own story.

This is another of those roving commissions in which I have been privileged to take part on more than one occasion.

If you think of the giant size of an electric tramway car or a railway train, and try to compare one of these with an electron, such as your humble servant, it will seem quite ridiculous that I should suggest that it is we electrons who move those huge vehicles. Yet such is the actual case.

Of course we require the application of very considerable power to urge us to so heavy a task. All the energy which we can get from a few electric batteries might enable us to drive a toy car, but when it comes to turning the wheels of a real car or train, we require a correspondingly greater amount of energy.

I may as well tell you quite frankly that we electrons are only the intermediaries or go-betweens. Indeed, you must have noticed that in every case we act merely as a connecting link between matter and the æther, and between the æther and matter.

But what I want to tell you of, is the part we play in moving an electric car or railway train. It is really all very simple if you could only see it from our standpoint. Picture a host of us attached to copper atoms in a coil of wire which is being moved through that disturbed æther called a magnetic field. We are set in motion immediately. It is true that when we are moved forward into the field we march off in one direction, only to be arrested and made to move off in the opposite direction as we leave the field, but it really makes no difference in our working capabilities as long as we are kept on the move. This is what is actually taking place in the armature of a dynamo as it revolves between the poles of the electro-magnet. There is no peace for us so long as the coil is kept revolving; we are kept in a constant state of rapid to-and-fro motion.

It is remarkable that the motion of electrons in an electric conductor can result in the movement of heavy vehicles. How this comes about is explained in Chapter XII.

This is all we electrons do in a dynamo, but when the ends of the outer circuit or mains are brought into contact with the ends of our revolving coil, we set the electrons in the mains surging to and fro in step with ourselves. Man describes this motion of the electrons in the mains as an alternating electric current, but by a simple commutator on the dynamo he may arrange that we set the electrons marching in one direction in the mains. This he describes as a direct electric current.

It is a matter of indifference to us whether man drives our coil round by means of a steam-engine, a water-wheel, or a wind-mill; all that we electrons want is to be kept surging or vibrating to and fro. Now you will be able to appreciate how we electrons get up sufficient motion to enable us to perform what I have described as our heaviest duties.

Perhaps you will find it difficult to believe me when I tell you that as we march along the connecting wire to a distant tramway car we transmit the energy through the surrounding æther, and not through the wire. This is our mode of working in every case, whether it be an electric bell, a telegraph, or telephone. That is to say, while we electrons move from atom to atom in the connecting wire, it is the disturbed æther surrounding us which transmits the energy. You must have realised by this time how very intimate is the relationship between ourselves and the æther.

To return to the tale of our tramway work, you will picture my fellow-electrons aboard the car being energised by the incoming current. Those electrons present in the armature coil of the motor are set into motion, as also are those in the wire of the neighbouring electro-magnet. The result is that these two sets of electrons so disturb the æther and affect one another that the coil is moved round into a different position. You will remember the experiment of which I told you, in which a magnetic needle would insist always in taking up a position at right angles to a wire in which an electric current is passing. Well, when the motor coil has turned into its new position, we electrons receive an impulse from our friends in the line-wire which causes us to retrace our steps in the coil. This action of ours causes the coil to make a further movement in the same direction as at first. Again we change our direction of march, and again the coil changes its position towards the electro-magnet. The sole duty of these electrons in the armature coil is to keep surging to and fro, while those electrons in the electro-magnet keep up a steady march in one direction. This arrangement necessitates the armature coil to keep changing its position continually, and when we have the armature coil spinning round at a steady pace, it is easy for man to connect the armature to the axles of the tramway car and cause us to drive the wheels round.

I need hardly say that it makes no difference to us whether we are asked to drive a tramway car, a railway train, or a host of machines in a factory or workshop. All that we electrons in the motor require is to have sufficient energy passed along to us from our fellows in the distant dynamo. Again I admit frankly that the atoms of matter play a very important part in these our heaviest duties, but you will see that without our active assistance they could not transmit the necessary energy to a distant car or train.

CHAPTER XIII
A BOON TO MAN

THE SCRIBE'S NOTE ON CHAPTER THIRTEEN

While it has been known for a long time that light and radiant heat are merely waves in the æther, it was not known until recently how these waves were produced.

The discovery of electrons has given us a reasonable solution of our difficulty.

The electron explains the actions of its fellows in this great work of producing light and heat.

Incidentally the electron explains how they produce an aurora in the heavens, and how it is that the earth has become a negatively electrified body.

Every living thing is dependent upon our activities. It is we electrons who send out heat and light from the sun, and it is we who receive these on their arrival upon this planet. Our action in the matter is really very simple, but until man discovered our existence, he was mystified considerably.

We were amused to hear man say that the atoms of incandescent matter in the sun produced waves in the æther, and that when these æther waves fell upon other atoms on this planet, these were set into a state of vibration, thus producing heat and light. Now if man had only stopped to think, he would have seen how ridiculous it was to speak of atoms of matter producing waves in the æther. He ought to have known that atoms of matter cannot affect the æther, for it offers no resistance to matter moving through it.

Man might have pictured himself riding on the back of this great planet, flying through space at a speed very similar to that of a rifle bullet, and yet even the flimsy blanket of air surrounding the planet is not disturbed by the æther through which it is rushing.

It is true that the atoms of matter play an important part in the origin of heat, but the atoms in the sun could no more affect the atoms on the earth than could a man on the earth push the moon about. It is the very intimate connection between us electrons and the all-pervading æther which enables our fellows in the sun to communicate with those of us upon this planet. Where would man be without us?

When a man is encased completely in an over-all made of flexible metallic gauze he is proof against shock due to a discharge of high-tension electricity. The part played by electrons in the case of electric shock is explained in Chapter IV.

I cannot understand wherein man should find any mystery in connection with this very simple action of ours. You will picture our distant fellow-electrons making very rapid revolutions around the atoms of matter to which they are attached as satellites. Just as the moon circles around the earth, so do we circle around our atoms, but at an enormously greater speed. Of course the whole length of our orbit is inconceivably small, and the speed of our revolutions is inconceivably great. It is our rapid motion through the æther which produces those waves known to man as radiant heat and light. Some one may ask how it is that we electrons can disturb the æther while the giant atoms cannot. The obvious answer is that we are not matter, but electricity; we are not in the same category as atoms of matter.

To complete the picture which I was drawing, you have only to think of the æther waves arriving upon this planet and disturbing sympathetic electrons, causing them to revolve around their atoms in similar fashion to our distant fellows who are producing the æther waves.

It may be that some people get confused between this action and that of those electrons who are shot off bodily from the sun towards the earth. Believe me, there is no connection between the two things. The stream of electrons shot off from the sun is deflected towards the magnetic poles of the earth, and as the electrons enter the upper layers of the atmosphere they produce that beautiful luminous effect which man describes as an Aurora.

I have never taken part in one of these great displays, for, as far as my recollection goes, I have never been in the sun, although some fellow-electrons declare that at one time we were all in the same great glowing mass of which the sun, and every member of the solar system, formed a part. However that may be, I certainly have no experience of auroræ, but I have assisted in producing the very same effect upon a small scale within a vacuum tube. The air remaining in these so-called vacuum tubes is just as rarified as the air in the upper layers of the atmosphere, and when we are shot across the tube we act in the same way as those electrons arriving upon this planet from the sun.

You will observe that as a surplus of electrons arrives upon the earth from the sun, the earth is naturally a negatively electrified body, but I need hardly say that the earth does not keep all the electrons which arrive upon it.

My scribe points out that I am wandering from the story which I set out to tell in this chapter, so I shall try and please him.

The direct cause of light, whether it be natural or artificial, is the rapid motion of electrons around atoms of matter. If they revolve at a comparatively slow speed they produce those æther waves which man calls radiant heat. If these satellite electrons, however, desire to affect the eye of man, they have to move around at a very much greater speed. If we travel at too fast a speed, then we cease to cause the sensation of light. But, believe me, all the waves we make are of the same nature, no matter what names man has given them. The only difference we can make in the waves is the rate at which they follow one another. Of course we can also make them larger or smaller in height, or, in other words, of greater or less amplitude, but that does not affect their properties.

In the following chapter I shall tell you of some remarkable phenomena which our different æther waves produce in the brain of man.