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CHAPTER VIII
A USEFUL DANCE

THE SCRIBE'S NOTE ON CHAPTER EIGHT

We believe magnetism to be due to electrons revolving around atoms of iron and other magnetic substances, as related by the electron in this chapter.

We have seen that the steady motion of electrons along a wire produces a magnetic field around the wire.

Therefore if we have electrons revolving round and round the atoms in a piece of iron, there will be a miniature magnetic field around each atom.

The electron explains why a piece of iron does not show the magnetic power locked up within it until it is "magnetised."

The electron refers to electro-magnets; an electro-magnet is simply a piece of soft iron with a coil of insulated wire wound around it.

The iron only shows its magnetic power as long as a current of electricity is kept passing through the surrounding coil of wire, for reasons which the electron explains.

I may tell you quite frankly that I have never taken part in the perpetual dance of which I am about to tell you. I am of a free and roaming disposition, but I have often watched some of my fellow-electrons at this work. Of course, it is pleasant work, as all our duties are, now that man acknowledges our services.

We are responsible for the behaviour of the mariner's compass needle. It is we who cause it to point continually in one definite direction. If we ceased to dance around the iron atoms in the compass needle aboard a ship, the man at the helm could not tell in what direction he was going, and sooner or later he would be almost certain to wreck his vessel. For this service alone man ought to be grateful to us, but before I have finished my story, you will find that even this important duty is but a small affair when compared with many of our other tasks.

There is one matter I should like to make quite clear to you. Although we electrons are all identical, we have different stations to fill. You have doubtless become familiar with my roving disposition, and you probably think of me as a detachable electron. Then there are our friends who are locked up within the atoms of matter – part and parcel of the atom. And now I am introducing you to those electrons who act as satellites to the atoms, revolving around them at a comparatively great distance, just as the moon revolves around the earth. These are the electrons which give rise to the magnetism in a piece of iron. There are other electrons which perform very rapid revolutions around all classes of atoms, but I shall introduce these friends later on.

That phenomenon known as "magnetism" is due to the steady locomotion of electrons, as explained in the text. Here we see a large magnet attracting a tinned iron box which is tethered to the table by two cords. The result is that the box is supported in the air. The spiral wires are connected to the electro-magnet, an explanation of which is given in Chapter VIII.

I need hardly remark that a piece of ordinary iron does not behave like a magnet. Indeed, it is fortunate that it does not. If it did, man could not get along with his work very well. The hammer would stick to the head of the nail it had struck, the fire-irons would stick to the fender, while the cook's pots and pans would hold on to the kitchen range. That would be a very stupid arrangement, but we electrons have really no say in the matter of arrangement. We are always on the move, performing a perpetual dance around the iron atoms, but the atoms arrange themselves in a higgledy-piggledy fashion, so that the electrons on one atom pull the æther in one direction while others pull the æther in an opposite direction. In this way the outward effect is not perceptible. When, however, man places a coil of wire around the iron, and makes a crowd of electrons march along the wire, these marching electrons affect the æther, which in turn influences the satellite electrons which are revolving around the atoms of iron. You may be somewhat surprised when I tell you that, owing to this æther disturbance, these satellite electrons are able to produce a rearrangement among the atoms. If you doubt my word, you may easily prove the truth of the statement. If you magnetise a long bar of iron you will find that its length is actually altered. This is due to our having disturbed the arrangement of the atoms.

Perhaps I should explain that when we force the atoms into their new condition, we can do so only under the æther stress set up by our fellow-electrons who are marching in the neighbouring wire. Whenever their march ceases the æther stress is withdrawn, and the atoms are able to fall back into their old higgledy-piggledy condition. In this way man is able to make a piece of iron a magnet and to unmake it as often as he cares by simply switching on and off the electric current from the wire surrounding the iron.

If a piece of hard steel is used in place of soft iron, then we find that the atoms are not so easily disturbed, but when they are once brought into line with one another, they will remain in their new condition after the æther disturbance has been withdrawn. It may seem strange to you that quite a small percentage of carbon atoms added to the pure soft iron should cause such a marked difference, but the matter seems plain enough to us. Man was so impressed with the manner in which the atoms were evidently fixed in their new condition that he spoke of permanent magnets. It is especially fortunate for man that these pieces of steel do retain their magnetism, and give us a reliable mariner's compass. But I shall tell you how you may disturb even these sedate atoms. If you hammer the metal very vigorously, or if you heat it to redness, you will find that the atoms have been freed from what appeared to be their permanent position, and they are back to their old higgledy-piggledy condition, so that we electrons are all opposing one another. Remember we are hard at work all the time although we may be giving no outward sign of our activity.

While we render an important aid to man by providing this permanent magnet for his compass, you will find that a very great deal of our assistance to man in his everyday life depends upon our behaviour in soft iron electro-magnets. It is in these that man can control our behaviour at will. It is through this simple piece of apparatus – the electro-magnet – that man has been able to accomplish so much in signalling to his friends at a distance. It is also by means of these electro-magnets that man can get us to turn an electric motor, and so on. But I must tell you, first of all, how we enable man to signal to a distance, or, in other words, how we carry man's news.

CHAPTER IX
HOW WE CARRY MAN'S NEWS

THE SCRIBE'S NOTE ON CHAPTER NINE

The electron explains wherein its method differs from all other methods.

It is well known that within recent years the old iron telegraph wires have been replaced by much lighter copper wires; the electron explains the reason for this change.

It describes how the electrons manage to work the most widely used form of telegraph instrument, which is called the "Morse," after its inventor.

Here we find one of the practical applications of the electro-magnet described in the preceding chapter.

It is we electrons who have so very far outdistanced all material carriers of news. You must acknowledge that the best runner, the swiftest horse, the fastest express train, and the prize carrier pigeon, are all nowhere when compared with us electrons.

But I do not wish to mislead you in any way, and I can speak from personal experience in this case. We do not race off with man's messages in the same sense as these other messengers do. Our swiftness of communication depends upon the simple fact that man provides a whole connecting regiment of us between the two distant places. And when the order to march is given we all move off at practically the same moment. In this way the electrons at the far end of the connecting wire are able to cause signals there immediately. This is the secret of man's success in being able to hold immediate communication with his distant friends. His success is due entirely to the co-operation of us electrons.

My personal experience has been in connection with a very simple telegraphic arrangement. Indeed, the most of our duties in transmitting messages are performed with this particular kind of instrument, known as a "Morse sounder."

At the time of which I speak, I had become attached to an atom of iron in the end of a long telegraph wire. From this you will probably guess that my experience was gained some time ago, for man does not use iron wires nowadays in fitting up telegraph lines. He used iron at first, and some of these lines still exist, but when he discovered that a very much lighter copper wire would serve the same purpose, he discarded the heavy iron wires. Man explained the matter by saying that the copper offered less resistance to the electric current, and the majority of people were quite satisfied with this kind of explanation. Of course these are merely convenient phrases which give man no real reason for the difference. The real reason is that we electrons are able to move about from one copper atom to another with very much greater ease than we can among the iron atoms. That is the reason why man made the change from iron to copper wires, although he had no idea of the reason at the time.

To return to my experience in connection with a telegraph instrument, I found that we were being subjected to a series of forced marches. The whole regiment of electrons along the line made a forward move. The line of march ended in a short length of fine wire wound around a piece of soft iron to form an electro-magnet. The end of the wire dipped into the earth, as I have explained in an earlier chapter.

Now all that we electrons had to do was to make a forward move, halt, forward again, another halt, and so on. Sometimes the signal to halt was longer in being given than at other times, but we found that this was intentional, and that there were two definite lengths of march. I have explained already how we marching electrons cause an electro-magnet to attract a piece of iron and let it go again as soon as we cease marching. It only remains for me to give you a general statement of how we work the Morse telegraph.

Man has arranged a little lever with an iron end-piece immediately above the electro-magnet, so that the magnet may attract it. Of course you are aware that it is the electrons within the soft-iron core of the electro-magnet who produce the magnetic effect. Every time we electrons in the surrounding wire make a forward move, the electro-magnet pulls down the end of the little lever referred to. As long as we keep marching, so long will the end of the lever remain down, but the moment we halt, the lever is free to be pulled up by a spring attached to it. The movements of the lever indicate the length of our long and short marches, and it is by means of these that man sends signals. All that he does is to control our march, by means of an electric push and a battery at one end of the wire, and it is we who produce the signals at the distant end of the wire. Each time man presses the push we move the distant lever. When we pull the lever down it is so arranged that it makes a sound like "click," and when we let it spring up against a stop it makes another sound not unlike "clack." Our long and short marches are therefore converted into long and short "click-clacks." Man has made a simple code of signals representing his alphabet, and right merrily do we rap out the signals for which we receive orders at the distant end of the wire, while some one at the other end listens to the sounds we cause to be made.

I have told you enough of our duties to let you see how we are able to carry man's news from one part of the earth to any other part. By far the greatest part of our signalling work is done with this simple Morse sounder.

It may interest you to note that we can produce those signals far faster than man can read them. When man found this out he took advantage of our powers. He made an automatic transmitter which could manipulate the make-and-break of the battery current far more rapidly than any human fingers could do. Then as we rapped off the signals with lightning speed at the distant end, he attached a little ink-wheel to the end of the moving lever, so that it could mark short and long strokes on a ribbon of paper passing close to it. Although man could not distinguish the signals by his ear he was able to read the record of those we caused to be left upon the paper ribbon.

We have been made to work many other forms of telegraph instruments. In some of these we control type-letters, while in others we imitate handwriting, but all these are merely adaptations of our powers of marching. We are proud of our achievements in rapid signalling, which all right-thinking people have not been slow to acknowledge.

CHAPTER X
HOW WE COMMUNICATE WITH DISTANT SHIPS

THE SCRIBE'S NOTE ON CHAPTER TEN

In this chapter the electron deals with that modern marvel —Wireless Telegraphy.

Here the æther of space plays a very prominent part.

The author has given some particulars about the æther in the first chapter (What the Story is about).

In conjunction with that, the electron may be left to tell its own story.

Our duties in this case are totally different from those of which I have been telling you. While we electrons can do many wonderful things, we cannot march through space. We may be fired off like bullets from the sun to the earth, but that is quite another matter. I shall have something to say about that fact later on. You have seen already that man can make us jump only a very short distance, even when he has cleared our path of the obstructing air, as he does in a vacuum tube.

If men were to provide us with a complete path of metal atoms from the shore to the ship, we could set to work upon the simple plan which I have described in the preceding chapter. But, needless to say, man has more sense than to attempt to keep up metallic connection with a ship going away out to sea.

Even the wisest men were surprised when they heard that we electrons could signal through space to great distances without any connecting wires. We ourselves were not surprised. Had we not been doing this very thing from the foundation of the world? Our fellow-electrons in the sun have never ceased to communicate with those of us upon the earth. Of course I am referring at present to those æther waves which man calls heat and light. But the waves which we make to carry man's messages through space are of the very same nature, the only difference being that they are much longer, or, in other words, much farther apart. They do not follow each other so closely, and they do not affect the eye or the sense of touch. However, these long waves are able to bestir some of us electrons who are situated at a great distance from the sending electrons.

Our method of producing such waves in the æther is by surging to and fro from atom to atom in an upright wire. When we make a rapid to-and-fro motion we send out great waves in the æther. The original plan adopted by man was to make us jump across a spark-gap, but in this case also it was our rapid oscillation to and fro that produced the waves. If we wish the waves to carry to a great distance, we must club together in considerable force to supply the necessary energy. The energy which we can get from a battery and induction coil is not sufficient for any very long distances. In such cases we require the aid of a dynamo, a machine about which I shall have some experience to relate in another chapter.

In communicating through space, our position is very similar to that of two men shouting to one another over a distance. The one man disturbs the air, thus sending air-waves (sound) over to his friend, and these waves produce certain sensations which he can interpret. I should like you to understand that we electrons are upon a higher plane than atoms of matter. We cause waves in the all-pervading æther, not among clumsy particles of air. After these æther waves have travelled enormous distances they retain sufficient energy to disturb electrons situated at the distant place.

I shall tell you of the first experience I had in this connection. I found myself attached to an atom of nickel, a kind of atom which looks to us electrons very much like an iron atom, because it has nearly the same number of electrons composing it, only they are arranged differently. But I was telling you that I found myself on this nickel atom sealed up in a small glass tube. Of course there were myriads of similar atoms all around me, but I did not feel very happy. I was being urged forward, and yet I could not get across from some atoms to others, for the nickel was in the form of loose filings. From past experience I knew that there was a battery along the line somewhere; I could feel the strain. All of a sudden I was startled to find that I could move forward. Exactly what happened, I am not at liberty to tell, but this much I may say, that it was the arrival of some æther waves which altered the condition of things among the filings in the tube.

It has become quite a fashion in America to have motor-cars fitted up for wireless telegraphy. That the electrons play an important part in telegraphing through space is explained fully in Chapter X.

We had just started out on our march forward when we received such a shaking that we found ourselves in the same isolated positions as at first; we could not get across from one particle to another. More æther waves arrived, we made a fresh start, then came another rude shaking, and so on we went starting and stopping. Indeed, it was the regularity of these long and short marches that gave me the first idea that we were being controlled by some telegraph operator. We were amused to find that the rude shaking, of which I have been telling you, was caused by the action of some of our fellow-electrons. Some of them in their march around an electro-magnet in the receiving instrument caused a little lever to knock against our tube and give us a sudden jolt.

I should like you to notice that the energy with which we moved the telegraph instrument did not come from the distant station. It was a local battery which worked the receiving instrument, but this battery was controlled by the incoming æther waves affecting the tube of filings. There is really no mystery about the matter, but I am anxious not to take credit for anything more wonderful than we have actually accomplished.

We electrons have rendered a very great service to man by enabling him to communicate with his friends who are far out on the ocean, and cut off from all possible chance of material communication. We are willing to serve man on land also, though we very much prefer the ordinary marching arrangement if he will provide a connecting wire. The fact is that we find it very much more difficult to send æther waves over land than we do over water.

I have heard some men ask how many different telegraph instruments may be worked at one place simultaneously without confusion. That is a question for man himself to answer. We electrons are able to produce any variety of waves of different frequency or length; it remains only for man to construct apparatus that will respond only to a definite rate of waves. I hear that man has made considerable progress in tuning the wireless instruments.

Some men are eager to get us to carry messages through space across the great oceans from shore to shore. We shall not refuse, provided man supplies sufficient energy, but I must admit that we electrons prefer the submarine cable. Of course man may put this down to our laziness; we certainly prefer as little severe straining as possible.

I have been telling you of my earliest and only personal experience in connection with space telegraphy. I understand that greatly improved methods have been adopted since that time, but I have never happened to drift in their direction.