Part 2

The science of Radio has taught us something of light, but only to a modest extent, for light yet remains one of the most inefficient factors of a civilisation which almost entirely depends upon it for existence.

There is a strange factor which we may call the “Law of Supply and Demand.” This strongly implies the faculty of invention, a facility of “wishfulness to improve”; something far better than the necessity for invention. Let us remember that our clothes are not necessities; they are merely comfortable, and it is comfort that distinguishes us to-day just as it is convenience that will in the future give us a life which will be better by far than that experienced by the kings and princes of to-day.

Civilisation has depended almost entirely upon the speeding up of communication. We can travel fast; we can convey our thoughts at great speed, but, unfortunately, although all these means of intercommunication are devised with the one idea of preventing physical work and of obviating the movements of our gross bodies, our senses are very closely combined. It is consequently not possible to ring up somebody on the wireless telephone, a fact itself easy of accomplishment, and to impress our personality upon the listener. This is simply because we require a combination of senses for hearing, seeing, smelling, and other reactions, in order to convey our whole personality.

Vision at a distance is, therefore, very necessary as our inclination for travel decreases and its comfort increases.

It is also important from the point of view of “speeding up,” which we have no reason to suppose will cease. All operations have steadily increased in speed for many generations.

There was a time when we made appointments to meet our friends at the full of the moon, but now we say at “10 o’clock, and I can only give you two minutes.” In the future we shall probably say, “Meet me at 10.2.1-5 secs., and do not keep me waiting.” To do this we must have radio sight.

Many years ago, when experiments were made on the subject, the usual cry appeared from what I always mentally typify as the “Flat Earth Brigade”; they said, “Impossible.” What would our forebears have said of talking to a man in an aeroplane? “Impossible!” It is a foolish word. Now all over the world experiments are being conducted, many of them with success and some with the guarantee of reasonable success in twenty years or less.

Now wireless, if I may apply the word here, is very like light in many ways; it is capable of refraction and shadow effects; it travels at the same speed, and if the wave-lengths of wireless could be sufficiently shortened to become visible we should probably find ourselves with a new, and possibly effective, method of transmitting wireless light and even power.

Radio is a phenomenon of the spectrum like ordinary photographic light, X-rays, and so on. It is effects which determine the difference to our eyes of things invisible, solid, and transparent.

It may well be that, when we succeed in inter-planetary communication, we shall discover that the inhabitants see by the X-ray, by wireless, or by heat.

It is not difficult to obtain a proportionate interchange of radio and light oscillations. Even sunlight affects wireless telegraphy, and experiments which have been conducted upon the carrying and directional power of certain other rays and oscillations have not been entirely without results. We may, one day, obtain far greater sensitivity of direction, greater carrying power, from small initial output with a degree of selectivity almost infinite, in comparison with modern working.

To use a light beam along which we can talk, to use a light beam initially and to turn it into light when required, is by no means difficult; it suggests the direct method of wireless vision, but from the mechanical aspect the problem is still less complicated. The difficulties of Radio Television to-day are constructional; in the far future it may be a question of pure physics.

There is, at least, one simple method of sending photographs by wireless with a reasonable degree of accuracy. Distance, re-broadcasting, relaying are, none of them, of any great technical importance. Interference is certainly a difficulty, for in the case of a picture the eye cannot distinguish between faults so easily as the ear can automatically separate unpleasant noises from music.

If an ordinary photograph is transferred to a copper plate, either flat or round, and a contact finger is allowed to pass over it, clearly the resistance between the plate and the finger will vary with the thickness of the photographic film. If this resistance is used to modulate the transmission in place of an ordinary microphone for speech, the current at the receiving end can be picked up, amplified, and used to mark darkly, lightly, or not at all, upon a prepared piece of paper which is affected by the passage of an electric current.

By these means good photographs can be reproduced, and doubtless in the future we shall be able to sign our cheques by the rapid transmission of motion; we shall be able to trace criminals, send out their finger-prints, and carry on very many classes of business which, at present, require our bodily attention.

What a help to the man who objects to a large city. Why could he not conduct his business from his house in comfort instead of having his spats washed every week in order to maintain his financial reputation?

There is a still more rapid method of transmitting a photograph: it is to allow the light from an ordinary lamp to pass through a spot upon the negative and then to a selenium cell. Selenium is so constituted that its resistance to the passage of electricity varies with the amount of light to which it is exposed. This property has been used to light up and to extinguish ordinary street lamps, for demonstration purposes.

If a selenium cell is used in place of the ordinary broadcasting microphone, the transmission can be modulated in accordance with the passage of the light through a black spot on the negative, such as part of a top hat, or a white spot, such as a white face or part of it.

The received current is picked up and amplified in the ordinary manner, but instead of operating a diaphragm to produce speech, it is taken to a kind of electrically operated venetian blind, which allows light to pass through it or not to pass through it, in accordance with the transmitting current.

It requires little imagination to see that, if a beam of light is allowed to pass through each point of the original negative in turn, the final picture can be built up from “spots” somewhat in the manner of a half-tone block.

It takes a long time, is rather patched, and is liable to interference; but the whole process is perfectly simple. Consider the great importance of this experiment to Radio Television.

The human eye sees only one point at a time but in the fact that instantaneous vision of a complete picture is not necessary lie our hopes of television to-day.

The eye is a very defective piece of mechanism considered from an optical standpoint. The pointed rays which appear to come from stars show one example of faulty optical construction, however wonderful may be the whole structure. Another property, and a feature of great importance from the aspect of television, is that of retentivity.

We all know that when a lighted cigarette is whirled round in the hand the result appears to be a ring of fire. Our brain assures us that the eye is telling lies and that it is really a moving point. This is because the image is impressed and actually lasts upon the eye or its retina.

This phenomenon is used in every cinematograph; without it the ordinary film would not be practicable. Each picture of an arm about to light a cigarette shows the arm constantly closer and closer, and before one picture has had time to die out the other is thrown upon the screen. The result is an illusion of motion.

To return to the transmission of a photograph, let us imagine that it is sent in a series of spots beginning in the top left-hand corner at 12 o’clock: the bottom spot will probably be completed, at modern sending speeds, by about 12.15, in the case of a picture two inches square.

Clearly all we have to do is to reduce this time to 4/5 of a second altogether, and we shall be again sending the first spot before it has had time to die away from the apparent vision of the observer. In other words, we will see by wireless.

The obvious method of assisting in this speeding up of sending the thousands of spots, would be to graduate them by some means of rotary conversion or to decrease the number of spots. The latter is one method by which practical television can be accomplished to-day.

It would be quite easy to fix up an apparatus by means of which we could show whether an office in New York was lit up or not, the observer being situated in London. This is a form of energy or combination of phenomena which amounts to wireless sight, but it does not help us to see shapes or forms or to say if the light is from a candle, the sun, or an arc lamp.

By increasing the number of cells from one to, let us say, twenty, we could possibly indicate the difference between the moving shadow of a cross or a circle, but to radiate detail is a very difficult problem, which doubtless will be partially solved within the next few years. The electro-magnetic theory of light and the phenomena exhibited by the neon tube, present many opportunities.

What an excellent invention this will be! It means that a telescopic camera could be attached to an aeroplane and the views seen by thousands in a cinematograph theatre who may have the pleasure of witnessing the finish of a horse-race and knowing without loss of time how much money they have lost.

It would mean that the crew of a ship, a submarine in difficulties, or the passengers in an aeroplane, might be visible to people many miles away. It could not yet occur without their wish, for the transmitting apparatus must first be put into operation.

The senses of seeing and hearing are possibly amongst the most important of all, and, if we can convey both of them to a distance, it means that we can call friends, nations, music, and personalities to our fireside, by the touching of a button.

Such possibilities need no enlargement. Wireless may prove a far more rapid link than the ordinary increase of travelling speed and may help nations to intermingle to the common good.

The question of seeing in colours has hardly yet been considered, but that also will come to us, however great the difficulties may appear to-day.

Certainly Leagues of Peace will have more arguments, and Generals will have more weapons.

The laziest millionaire to-day, in a physical sense, will be hard-worked in comparison with the fortunate individual of the scientific future. We will travel in the best possible manner and in such comfort that the mind will be free to receive impressions. Our main objective will be to train it for that purpose.

After all, what more can we do now?

WIRELESS AND WAR

The subjects of War and Wireless cover a multitude of closely allied ills.

It is only natural that wireless should first have been applied to Love and War. I remember well one of the most remarkable applications of wireless mentioned in the press in the early days was that of a cable sent to an unfortunate man in mid-ocean, informing him that an all too successful arrival of twins had taken place.

War is, of course, a natural process a little less educated, and more unkind, in consequence, than birth control.

Most inventions are first applied to the science and art of warfare. Perhaps we should not regard this as all to the bad, for War has a remarkable capacity for acceleration.

Development of the wireless valve was greatly assisted by the War: the aeroplane, the art of plastic surgery, and many other human benefits have arrived more rapidly from the same cause.

Let us see, therefore, what wireless can do now, and what it may accomplish for the future of organised destruction.

Mentally, the fittest should survive, in both the realms of invention and physiology. It is only a few years since wireless was of no intrinsic value for ordinary land warfare, by virtue of the fact that interference was extremely easy, and that any coded message could be so easily decoded.

At present wireless messages are chiefly of service where secrecy is not of such importance as speed; but an enormous number of experiments are being conducted upon beam wireless, directional wireless, and in the combination of the Radio oscillation with some other oscillations such as those of visible or invisible light. By these means secrecy will be obtained when we discover how to use small powers for long distance, but at present Radio is chiefly of value as a time-saver.

The pilot in an aeroplane can talk to his base: he will soon be able to write and transmit vision from a plane which could be controlled by wireless. The time will come when low-flying wireless planes will explore, and render visible at many miles distant, places where no human pilot could remain for any length of time in safety.

It is not long ago that we rejoiced because a damaged ship was able to call for help by wireless, but we have only to look back to a recent war to remember an occasion when one ship was totally unable to call assistance because its wireless was jammed. In other words, enemy interference was possible.

This should show us how far we have yet to go in an utterly new and very little understood science.

We began with sparks, we progressed to coherers, and now we have valves; but let it not be thought for a moment that the valve represents finality to any thinking being.

Broadcasting at present has really become so universal only on account of the exceedingly public nature of wireless, for, when we are able to obtain accuracy of tuning and direction, we shall not only use the latter to guide ships at sea, but we shall have correspondence which can be conducted with a reasonable degree of secrecy. We shall have special wave-lengths for the Government, special wave-lengths for Parliamentary debates, and the Divorce Courts. We shall not conduct our conversations in such a manner that any schoolboy with a piece of wire, a needle, and some sugar, can promptly listen in.

The very idea suggests a new “Peeping Tom.”

As far as communication is concerned, we shall have whole armies in instantaneous touch with each other: it may indeed make real secrecy more difficult. It should always be recollected that when we refer to wireless speech, wireless control, and Radio Vision, we do not necessarily mean the same form of electrical wave by which we now broadcast a comic opera.

It is with oscillation that we are really concerned, and we may discover many forms of electronic vibration at present occupying portions of the so-called spectrum which are as yet very little understood.

It may be impossible for the Commander-in-Chief of the future to conceal a document from the eyes of wireless; and who knows but that the electrical operation of thought may be reduced to a science so that our very ideas are not secret without protection?

How many of us to-day could risk all our thoughts being known? It would probably improve moral standards if they were published: science tends to effect an average improvement.

We have never yet really seen the extraordinary value of wireless in war. If we had solved the problem of selection, the transference of speech by phonograph records dropped from aeroplanes would never have arisen.

Undoubtedly, we shall see wireless controlled tanks, submarines, and torpedoes on both land, air, and water. All will be accurately controlled, and they will possibly be able to find their way home and to operate from a distance while out of sight.

Even to-day it is possible for an aeroplane to operate a torpedo, to steer it properly, to slow it down; and for a pilot of an aeroplane many miles away to work his will upon it with a reasonable degree of accuracy and with the help of a gyro control.

The day will undoubtedly come when the problem of defending an island is not that of the mainland itself but of all its dependencies.

No large town could live for long if it were bombed from a distance by wireless, if gassed and poisoned from a distance, were it not for the balance of protection and defence which is usually maintained by nature.

We shall in the future, see forms of electric death and heat-rays which may materialise not as a direct projection of heat but as some form of oscillation which produces heat only when striking a metallic object.

We have been so often told that power can be transmitted by Radio that we are apt to look upon this statement with contempt. This is quite wrong: power will one day be transmitted by wireless; power can at present be inductively sent over quite a large air gap, though the energy available quite close to any wireless station is practically negligible to-day.

When motor-cars and ships are controlled or stopped by wireless, it is not the wireless which does the work; the therial oscillation merely sends signals to the ordinary operative mechanism.

Much excitement has been caused by the alleged injury of aeroplanes and motor-cars by wireless, but how is it that they can afterwards proceed? Do we forget that the petrol engine has to be restarted, and that, if allowed to fire when a car was in gear, it might be damaged and would probably not operate the moving parts?

If wireless power could be directed in such a form that it could be conveyed along a wave of “atomic” oscillation, many more valuable ends might be served than the enforced landing of aeroplanes.

Our clocks could be corrected by wireless, experiments could be conducted upon the nature of light and ether in various forms. We might decide the mode of propagation of light and thought, and investigate the apparent motion of the electron along the electro lines of force.

What an opportunity for study to the man of medicine! What a chance to find out how the oscillations of life are connected with those we partially understand.

What a chance for the burglar to discover the presence of hidden spoons as a mass of metal by means of wireless; what a chance for the surveyor and the seeker after oil to use this all-prevailing sense of oscillation and even to discover the meaning of radiation.

Oscillation--that is all we mean by Radio; and oscillation is at the base of life itself. It will not be long before travellers by air, land, and water, will be no longer alone.

That they will be able to converse with their homes may seem no advantage, but that they can remain in touch with the rest of mankind is most obviously desirable.

If this were understood to-day, I should not need to make noises with my lips or require the simulacra of these noises to be produced upon paper to convey my thoughts. If thought is a process of energy-conversion--and who will deny it?--what form of screening prevents its use, and why should its reception be confined eventually to life upon this particular and very troublesome planet?

It is remarkable how little is known of wireless: the very simplicity of its painfully standardised features is a trap for the unwary. It is a universal science, but we do not yet know the correct diaphragm size for a loud speaker, nor how damping should be employed. The finest apparatus is available to all, and yet we do not understand the fullest range of wave-lengths. The study of radio-active materials and short wave radiation may in one day produce the cold-emitter valve, abolish the outside aerial, and bring to our closer understanding some of the many senses now so atrophied in mankind, that we can only speculate as to their existence. I doubt much if the schoolboy of the future will greatly esteem the radio expert of this century.