Chapter XIV: How We Produce Colour

In the preceding chapter I have been telling you how we electrons produce waves in the aether ocean. I pointed out that if we make the waves follow each other at too slow or too fast a rate they fail to affect man's eyes.

It may seem strange to you that only a very small range of our aether waves should affect man's visionary apparatus. Of course this limitation lies beyond our province; we can produce endless variety of aether waves--it is man's organs which fail to appreciate the bulk of these. However, there is plenty of variety in the sensations which we can produce in man. If we make the waves follow each other at a certain speed, man says he has the sensation of _red_. If we move faster, he speaks of _orange-colour_, and as we increase our speed he names his further sensations as _yellow_, _green_, _blue_, and _violet_. Then if we combine all these waves--that is, if we produce them all at one time--he says he has the sensation of _white_. If we produce none of these waves, he calls the result _black_.

While we electrons are very versatile, our actions are dependent in a great measure upon circumstances. For instance, if an electron is acting as a satellite to one particular kind of atom, its rate of revolution around that atom may be very different from that of an electron similarly attached to another kind of atom. We electrons are all identical, but the speed of revolution is determined by the kind of atom. The reason is very simple; electrons revolve around some atoms at a much greater distance than they would around other atoms. Those making only the smaller orbits not only get around their atoms in less time, but they are also travelling at a greater pace. It is this fact which enables the electrons to produce the various wave-lengths which stimulate the different colour sensations in the brain of man.

I think you will have no difficulty in seeing how it is that we come to produce such a variety of wave-lengths--in other words, how we are able to make the waves follow each other more or less rapidly. You will understand that we do not produce colours; we merely make various waves in the aether, and these waves excite the colour sensations in man. I mention this simple fact, because I hear many people speaking of our aether waves as "coloured rays," which, of course, is quite a ridiculous description.

Suppose some of those waves which give rise to the red sensation happen to fall upon a lump of matter which contains only electrons capable of producing waves that affect the green sensation. What will happen? There will be no response, and the object, although viewed by "red light," will appear black.

If an object, such as the white paper upon which my scribe is recording my story, contains a variety of atoms with electrons capable of revolving at all the different rates which produce colour sensations, then when "white light" falls upon the object it appears white (all the colour sensations combined). If, on the other hand, a "red light" only falls upon it, then only the electrons capable of responding to that rate of wave will be set in motion, and the object will appear red, and so on with the other rates of aether waves.

So far I have been telling you what happens when different waves of light fall upon us. Now I shall endeavour to explain how man has caused us to produce artificial light. At present all man's methods in this direction are dependent upon making some substance so hot that it becomes incandescent. Even his most modern methods seem to us to be ridiculously wasteful and most roundabout. I shall speak only of the electric glow lamp, as I have had some experience in connection with this.

On one occasion I had been taking part in a regular forward march from copper atom to copper atom in a conducting wire. I had no idea of the purpose of our march till I suddenly found myself handed over to some carbon atoms, who were in a very lively state of vibration. We had much more difficulty in making our way through this substance, and it was the passive resistance offered to the advance of the electrons who had preceded me that had driven the carbon atoms into this state of great excitement. In our march through the copper conductor we had been offered very little resistance, so that we had left the copper atoms in peace--at least man could not detect easily any excitement (heat). But so long as our forced march was maintained among the carbon atoms, so long did the high temperature exist.

You will understand I and the other marching electrons did not produce the waves of light sent out by the glow lamp. What we did was to set the atoms of carbon into a rapid vibratory state, and they in turn caused their satellite electrons to hasten their pace. Some electrons produced one rate of waves, and some another rate, but by the time the carbon was incandescent there were electrons sending out all the variety of wave-lengths, the combination of which produces the sensation of white.

I have accused man of adopting very wasteful processes, so I had better explain the matter. In the preceding description of what is occurring in an electric glow lamp, I have spoken only of those aether waves which constitute light. But there are myriads of electrons in the carbon of the glow lamp that never attain the requisite speed to produce those waves; they revolve around their atoms at too slow a rate. They certainly disturb the aether, but the crests of the waves are so far apart that they do not affect the eyes of man. The business of these waves is to set up heat in the bodies upon which they fall. You may be surprised to know that in this contrivance of man, called an electric glow lamp, and, indeed, in all his other artificial light-producers, he causes far more electrons to produce radiant heat than the desired light waves. A most wasteful process!

Man has a long way to travel yet before he succeeds in producing artificial light by a reasonable process. Indeed I doubt if any of you can realise, as we do, how exceedingly stupid the existing methods are. Think for a moment of the glow-worm, in which we electrons produce light without setting up any wasteful heat waves. There is a strong contrast between this peaceful plan and that of the excited carbon atoms. When will man succeed in discovering this secret of ours?

CHAPTER XV

WE SEND MESSAGES FROM THE STARS

_THE SCRIBE'S NOTE ON CHAPTER FIFTEEN_

It is remarkable that man has been able to discover what the
distant stars are made of.

Our knowledge concerning the chemistry of the stars has been
obtained by means of the spectroscope, in which a beam of light
from the star is passed through a glass prism.

The result is the well-known image of the coloured spectrum, in
which certain well-defined lines appear, according to the
distant elements originating the aether waves.

The electron explains the whole subject from its own point of
view.