Wireless Possibilities
Date: 2021-12-16T00:00:00+00:00
Keywords: Radio

The Project Gutenberg eBook of Wireless Possibilities

This eBook is for the use of anyone anywhere in the United States and most other parts of the world at no cost and with almost no restrictions whatsoever. You may copy it, give it away or re-use it under the terms of the Project Gutenberg License included with this eBook or online at www.gutenberg.org. If you are not located in the United States, you will have to check the laws of the country where you are located before using this eBook.

Title: Wireless Possibilities

Author: A. M. Low

Release date: December 16, 2021 [eBook #66951]
Most recently updated: October 18, 2024

Language: English

Other information and formats: www.gutenberg.org/ebooks/66951

Credits: Tim Lindell, Martin Pettit and the Online Distributed Proofreading Team at https://www.pgdp.net (This file was produced from images generously made available by The Internet Archive/American Libraries.)

*** START OF THE PROJECT GUTENBERG EBOOK WIRELESS POSSIBILITIES ***

WIRELESS POSSIBILITIES

WIRELESS POSSIBILITIES

BY

A. M. LOW

Late Hon. Asst. Professor of Physics
at the Royal Artillery College
Author of “The Two-Stroke Engine,” etc.

With four diagrams

New York
E. P. DUTTON & COMPANY
681 Fifth Avenue

Copyright 1924
By
E. P. DUTTON & COMPANY

All Rights Reserved

Printed in the United States of America

TO
JOHN LOW

PREFACE

The effects of history upon the advance of science are often noted, but the result of the march of progress is more often entirely neglected.

It would seem desirable that the future should be studied with reasonable accuracy if we are to protect ourselves from the ill-effects and obtain the benefit from the good fortunes of invention.

A.M.L.

WIRELESS POSSIBILITIES

INVENTION

Considering the very evident fact that we owe every detail of our lives, every little comfort which separates us from the cave-man, to the science of invention, it seems strange that so long should have elapsed before this remarkable faculty received proper recognition.

Invention, in many ways, is the science and art of continuity of thought. The inventor is often referred to as a strange person; very true, very necessarily true when we realise that his doings must be strange or new, to be of value. To train oneself to forget the smell of the beefsteak when hungry and to continue the natural sequence of ideas which may be passing through the mind, is to train the brain to improve. If we can but sweep a crossing a very little cleaner than that next to our own, perhaps we have surely accomplished one of the greatest duties of all.

If not one day is spent without something learnt, surely we have achieved the greatest object of work and enabled ourselves to realise that there are no such things as basic facts.

Invention is not labour, for the latter is doing something we do not wish to do in some one else’s time, and invention like all good things is a work of love. Possibly that is why it is never paid!

We are too apt, I think, all of us, to rejoice in our greatness as her devotees rejoiced in the greatness of Diana of the Ephesians: we should realise every time we undress that we are little removed from the animal, and that before many centuries have passed we shall be held in almost universal contempt.

If that does not stir us to do our best, we are indeed a nation of shopkeepers. But even the proprietor of the meanest store relies on his powers of prophecy for his profits.

The science of wireless is but a few years old. We know about it little more than our schoolboy sons, and in many cases not so much; let us therefore be open-minded if we are still ignorant.

Commercial invention trusts too far to mass thinking: an original mistake is very closely related to an accomplishment.

THE IMPORTANCE OF SOUND IN WIRELESS

A few lines of history are desirable here. I do not mean the history controlled by the fact that William the Conqueror made many important appointments in A.D. 1066 or that Stephen was particularly busy in A.D. 1100. I mean the history of wireless, for, although Radio Science is new, it has a history; all time is relative, and we ourselves are functions of that phenomenon.

Only a few years ago the efforts of wireless experimenters were entirely directed to the converting of the extremely delicate wireless oscillation, still but little understood, into a mechanical movement, in order that the motion of electrons in a problematical aether (which may be nothing but a thought projection and which may exist in many different forms) might be altered into something readable by a man with a check waistcoat and a stock and share list in his hand.

That particular use, and the information that one army is about to kill another could be transmitted to headquarters, naturally occurred to everyone as the first valuable applications of Radio.

The many devices, the electro-magnetic receivers, tape machines, coherers, syphon recorders and the thousand and one electrical machines produced at the time for these purposes, have practically all gone.

Even when to-day we want to send messages quickly, we record them upon a Dictaphone and rely almost entirely upon the sense of hearing.

Sound, the regular oscillation, and noise, the irregular oscillation, of the air, are really the beginning and end of wireless as it is known to the public to-day.

I would go further when thinking of the public. They do not want to sit with a telephone upon their heads, even if their ears may be improved thereby. They require to walk into a drawing-room, and having stood for a moment upon the mat, they must be able to cross the room, touch a button in a fretwork cabinet, and by the movement of a lever be able to place themselves in touch with any part of the world. Paris, Hong-Kong, London, all must be one to them if we are to get their money for our art.

In other words, we are compelled to use what we now designate the “loud speaker.” We have got to project a sound into the room before we can sell our instruments, and therein lies one great difficulty.

In the first place we dare not exaggerate the movements of a delicate telephone very much or we shall spoil it—therefore we construct something which looks very much like a magnified telephone with a trumpet upon it. The mechanism is naturally rather heavy as regards the moving parts. In order to vibrate these heavy parts with the aid of our aetherial oscillations we have to amplify the available current, and during this process we naturally spoil the detail, or, in other words, we magnify it so much that electrical distortions occur through the whole range of various transformers and other items sold by every shop in the world—at double their value.

Most people are not content with a gentle sound: they find it necessary to express their joy at having reached their home by dancing; consequently they want plenty of sound, and they do not mind if it turns into noise.

They will tell you boldly that their wireless set with a couple of dozen foreign-made valves can be heard right across a large street, a street by the way in which we still permit as much nerve-shattering noise to occur as is thought necessary. This means that we must have quite a big movement on a diaphragm of large size, and a large diaphragm is made to move by the electrical oscillation, itself not very accurate; naturally, if it is heavy, like a poker or anything else, it has a will of its own, and therefore it continues to move when the wireless oscillation has told it to stop. It does not even commence to move when it is told to do so, as it would were it a thin delicate telephone diaphragm from which accurate music can be obtained.

This means further distortion, and so bad is it that a great many people say plainly that they will only listen to wireless concerts through a telephone and that they will only use crystals to obtain rectification because of the inaccuracies otherwise unavoidable to-day.

But this is not business, because do not forget we must have our cabinet with a fern upon it and beautiful music, if we are to be successful. Business always leads science, as we know.

Now think why it is that we need this big diaphragm moving so hard to get a big noise; let us neglect electrical details and consider what produces the noise; or sound, if we are lucky.

Sound is unfortunately purely a mechanical phenomenon as we chiefly understand it, and is produced by oscillations, alternate compression and rarefaction of the atmosphere. Unlike the aether, which sometimes oscillates only too readily, air is a heavy material and has great mass.

You will soon find this out if you put your head out of a railway carriage window, because the air is so heavy that we have got to really kick it and hit it hard before we can obtain a reasonable degree of noise.

When a speaker is standing at one end of a room, irrespective of what he says, the actual temperature-rise of the air can be measured, a fact which was used during the war for the inspection of sound.

Sound is a very complicated thing. It can be reflected in much the same way as light, and I suppose most school-boys know that if a concave mirror is at one end of a room and a similar mirror at the other with a watch hanging at its focus, the watch cannot be heard by an observer walking across the room, yet as soon as he places his ear at the focus of the other mirror he will hear the tick clearly, showing that sound is easily reflected. Everybody who has heard an echo should know this.

Sound travels also very slowly, and there is plenty of time for wind and different mechanical scraping effects to spoil the purity and partially absorb its delicacies.

Remember that if I am addressing a man by wireless who is one hundred miles away, someone who is listening on a telephone will hear my voice before I am heard at the end of the big hall where I am speaking, because the velocity of sound is only 1100 feet per second, and wireless, like light, travels much faster. Sound can also be actually refracted. Just as the old-fashioned jeweller used a globe of water to concentrate the light upon his work, so will a collodion balloon filled with carbon dioxide, the ordinary gas product of average combustion, act as a lens for sound, which can be actually focussed by these means.

This exemplifies the complication of our subject, and indicates that the heavy diaphragm and other details of the loud speaker must produce serious distortion.

Let us be honest at once. We can only hear such distant places as America by the grace of heaven. Even Sunlight can tune sweet song into vague cracklings. Until true tuning can be obtained we are largely at the mercy of the reproducing instrument, which too often exaggerates every fault and gives the impression that wireless and music are in no way related. No loud speaker of to-day really produces voice and song which sound exactly like voice and song. It all too much resembles a bad gramophone, but without the advantage of the user having the choice of the music.

If user and manufacturer would concentrate upon obtaining purity, if they would try the effects of damping upon loud speakers, which are easily obtained; if they would realise that the horn of the loud speaker should be without resonance, that it should be also damped and pocketed, that its goose-necked shape is not adopted without an object, and if they would aim at the delivery of true music instead of noise—then, we should make a great advance. The average loud speaker can often be greatly improved by padding the horn with some kind of tape, and as an example of the great difficulties of proper transmission let it be made quite clear that with most cases of wireless communication the sending is nearly perfect. Reception is greatly at fault: it is the reception that mangles the sound and makes it too often almost unbearable to anybody of reasonably sensitive hearing.

At some large transmission stations it was at one time quite common to use three separate microphones for the modulation. One received notes of high pitch, one of low, and a third attempted to obtain the “S” sound with the result that, when this “S” microphone was adjusted for a man who did not say his “S” very loudly and someone appeared who did, it sounded exactly as if the speaker had dropped his false teeth.

All this is now avoided. The ordinary diaphragm is no longer in use, but a very small coil of aluminium wire is suspended between the poles of an electro magnet, allowed to rest against an ordinary pad of cotton wool, and that is all!

The infinitesimal movements of this aluminium coil will reproduce speech up to about 40,000 periods per second in oscillatory speed, yet speech is well recognisable if all frequencies over 4,000 per second are gridded out.

How difficult it is going to be to make a large, heavy, and rapidly moving diaphragm reproduce accurately when we have had to take all these precautions to obtain accuracy of transmission! It is not impossible; it will come one day.

Now let us see what is the result of our sound troubles.

We are told that before long it will be quite easy to hear birds singing in trees and the waves beating against the seashore. Quite right, quite easy to do it now, but if a bird singing in a tree sounds like a man moving his condenser or walking about with a pair of squeaky boots, is it progress?

Perhaps it is. The whole point of wireless is that it brings a man into your room, but it must sound like the man himself if it is to be really effective; it is this pitiful quality of reproduced sound that has wrecked the talking cinema.

It is very easy to photograph sounds and to reproduce them simultaneously with the projection of a picture, but to reproduce all the sounds of a cowboy scene accurately is, at present, almost impossible. If a hero says “Good-bye” to a heroine with a kiss like a creaking board, in the middle of a twenty-reel drama, instead of improving upon the effect of your imagination, which tells you that it is real, and which acts the scene for you better than it can be shown in life or sound, it would be like putting up a blackboard across the screen with the words written upon it, “this is not real—it is only a fake.” That is what is wrecking the talking cinema. As a scientific proposition it is easy, but the results are not good enough at present, and, if we can improve, let us first consider the loud speaker.

The talking cinema will come as a matter of course. It is so easy to record sounds upon the film by photography with reproduction by the selenium cell or the neon tube; it is easy to photograph the wave; it is easy actually to impress the sound wave upon the film with the picture, or to use a gramophone; but reproduction is not like a human voice. Neither as yet is any reproduction ever like the voice itself. Let that painful fact be remembered.

Unfortunately, from the business point of view, the long distance reproduction effect is usually satisfactory even when re-broadcasted upon telephones, and for business purposes it is immaterial whether the voice that records the profit or loss is harsh or pleasant.

So the greatest effects we shall soon see from wireless and sound are these: we shall be able to speak to people all over the world by relaying and a combination of land-line and radio; we shall easily be able to connect our office with a wireless station on the coast, radio across the Continent, and then connect by land-line to another office on the other side of the Atlantic.

All this is so easy that no one can doubt that we shall soon listen in to native jamborees; no one can doubt that we shall hear the strange cries of partisans at a baseball match taking place a few miles from New York; no one can question these things, and when reproduction becomes so accurate that the very nature of the people is revealed to us through their speech, surely we might be a little more neighbourly even with those whom we now pretend to love? Relations are notoriously quarrelsome.

If you are in a concert hall and the number of people is varied, it will alter the effect of the sound. You have only to look at a sound-wave photograph produced from a violin to realise from its dainty intricacies that the least variation of any of its harmonics or the very exact shape of its wave beats will reveal all the difference between a beginner and the finest musician in the world. But these things are seldom noticed in wireless.

It is quite easy to photograph a sound, by means of a diaphragm beside which a soap bubble is thick, and to compare wireless sound with the original; even then we have the great difficulties of resonance, and a diaphragm cannot reproduce properly. How, therefore, dare we neglect the dreadful sounds we hear in the name of radio music?

If a piece of silvering, one thirty-secondth of an inch, be scraped from the back of a mirror and fastened to the outer part of a celluloid diaphragm (made by water-floating a drop of amyl acetate in which celluloid has been dissolved), it only requires a horn and a beam of light to render visible the waves of sound. A diaphragm movement of a millionth of a millionth of an inch is sometimes audible.

It is the science of wireless that is beautiful; it is the possibilities that are wonderful; but to talk of pure sound and to judge of it by the human ear which varies after every meal, is like measuring the amount of current passing through an electric-light bulb by feeling its heat with the hand.

It is not generally known that, during the War, experiments were made with a sound-reflector for listening to different types of aeroplane and submarine, by means of a microphone placed at the centre of a concave mirror. The difficulty was that of distortion, which is the whole source of trouble with sound producers to-day. Distance is no difficulty and when we can obtain purity and realism as well as distance, the latter is no difficulty at all; then only will be the time when we shall have that spontaneous mental realism of vision that will help radio to alter the world.

In a few years time we shall be able to chat to our friends in an aeroplane and in the streets with the help of a pocket wireless set, and be able to do practically everything by the aid of radio that we now do with our voice.

The only thing that will seem intensely strange will be that these comforts never existed before!

WIRELESS INACCURACIES

I have often wondered whether people realise that broadcasting, at present, is only possible or, shall I say is only popular, because of its extreme impracticability for most forms of secret communication.

Supposing two people had been able to converse privately and with absolute secrecy from other “listeners in,” then we should not mind trusting all our messages to Radio. At present, what can be coded can be decoded, and we are not entranced by the idea of entrusting our pennies to the winds of Heaven and the vagaries of a thunderstorm.

If wireless had really been selective in the first instance, broadcasting would not have been its initial phase.

Wireless at present is excessively inefficient; a few yards from a large broadcasting station the power is measured in millionths of a horse-power, is disseminated in all directions, and is almost without definite selectivity.

When the day comes when we can tune with absolute accuracy; when we can combine waves with accuracy and obtain a directional beam with the shortest waves for re-broadcasting purposes, then we shall obtain real happiness from the results.

Parliament must have its special wave length, the divorce courts of the future will be broadcasted to prevent people from catching cold by waiting outside. It will be quite easy for the Judge, at a doubtful passage, to press a switch and to say, “I think we will cut that out.”

One can imagine broadcasting of the future linking up every city from China to London; one can see special wave lengths for men, and equally special wave lengths for women. And we shall forget the time when ships at sea with ancient sets interfere with the murdering of music by the local amateur.

It has been said that, at present, those in authority find it necessary to choose special voices for the wireless broadcast-delivering. What an idea! The public want to hear everybody. They want to have local events broadcast, irrespective of the operator. They do not want a perfect voice, they want a perfect personality, and it is rather the wireless that must be altered to take any reception than the human voice whose very characteristics delight us.

We are too accustomed to relying upon our senses. We are apt to think that the ear is most delicate. It is nothing of the kind; it cannot even hear notes that delight the heart of a dog, and if one pictures life with the brain of a man, the ear of an antelope, and microscopic eyes, together with the nose of a dog, some little idea of the inefficiency of those few senses which we slightly understand can be obtained.

To live in any town would be impossible: the smells of Bond Street instead of pleasing the dog would tell us of rotting animal matter and alarm us to distraction. We could never sit down upon a beautiful piece of grass without listening to the worms and imagining ourselves with them. We could not bear to drink water for the peculiar bodies we would see in it. The wind in the trees, the people walking down our street or into our rabbit-warrens of flats, would sound like a battle from afar.

It is only a question of relative senses, easily tested by anyone who has the patience to fit an effective microphone to the amplifier purchased in mahogany case at the local “store.”

Wireless inaccuracies abound; anyone who hears its music will agree, but what of their effect upon our bodies!

The air, popularly speaking, must now be full of radio oscillations, and if you tell me that they are negligible in effect I may believe you, but if I hear there is no effect at all, I know that it cannot be true.

It is more than likely that, in the far future, the proper study of oscillatory theories, the proper investigation of the spectrum only very partially explored by a few, will lead us to a better understanding of the nature of life, and will help us to appreciate the theories of electrical sonics. Theories of preventing local thunderstorms, of growing babies and wheat effectively, by electrical or other similar oscillatory means, of helping ourselves to see by wireless and of affecting our health at the end of many generations for the better, may all be developed in the time to come.

If some health effect is produced, why should we not try to render it beneficial? A small effect can be very cumulative in nature. One has only to inspect a human nail to agree with that statement.

RADIO TELEVISION

It has been said of sound that a bell never ceases to echo and that the human voice never ceases when once words are spoken; truly, it is an alarming thought when the nature of most of our sayings is realised.

Not long ago it was claimed that by means of a delicate microphone the sayings of Henry VIII had been investigated—though nature of the subject was, with not less delicacy, omitted.

Much the same basic ideas apply to light except that we are dealing with a very much more interesting phenomenon, one indeed which is not apparently too material and a sense which gives us nearly all our nonphysical sensations.

We actually transmit very few senses: we merely convert their nature by utilising different portions of the spectrum. Light has undoubtedly its tone values, as in the case of sound, and it has not yet been definitely established with what portion of the body vision is actually obtained. It is likely that light is projected along the electro lines of force by the movement of electrons but whether the ether consists of electrons themselves, whether it exists in many forms, or is merely a result of the mass effect of thought, we do not yet know. Light very possibly proceeds from the eye as well as from the luminous body concerned.

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.

*** END OF THE PROJECT GUTENBERG EBOOK WIRELESS POSSIBILITIES ***

Updated editions will replace the previous one—the old editions will be renamed.

Creating the works from print editions not protected by U.S. copyright law means that no one owns a United States copyright in these works, so the Foundation (and you!) can copy and distribute it in the United States without permission and without paying copyright royalties. Special rules, set forth in the General Terms of Use part of this license, apply to copying and distributing Project Gutenberg™ electronic works to protect the PROJECT GUTENBERG™ concept and trademark. Project Gutenberg is a registered trademark, and may not be used if you charge for an eBook, except by following the terms of the trademark license, including paying royalties for use of the Project Gutenberg trademark. If you do not charge anything for copies of this eBook, complying with the trademark license is very easy. You may use this eBook for nearly any purpose such as creation of derivative works, reports, performances and research. Project Gutenberg eBooks may be modified and printed and given away—you may do practically ANYTHING in the United States with eBooks not protected by U.S. copyright law. Redistribution is subject to the trademark license, especially commercial redistribution.

START: FULL LICENSE

THE FULL PROJECT GUTENBERG™ LICENSE

PLEASE READ THIS BEFORE YOU DISTRIBUTE OR USE THIS WORK

To protect the Project Gutenberg™ mission of promoting the free distribution of electronic works, by using or distributing this work (or any other work associated in any way with the phrase “Project Gutenberg”), you agree to comply with all the terms of the Full Project Gutenberg License available with this file or online at www.gutenberg.org/license.

Section 1. General Terms of Use and Redistributing Project Gutenberg electronic works

1.A. By reading or using any part of this Project Gutenberg electronic work, you indicate that you have read, understand, agree to and accept all the terms of this license and intellectual property (trademark/copyright) agreement. If you do not agree to abide by all the terms of this agreement, you must cease using and return or destroy all copies of Project Gutenberg electronic works in your possession. If you paid a fee for obtaining a copy of or access to a Project Gutenberg electronic work and you do not agree to be bound by the terms of this agreement, you may obtain a refund from the person or entity to whom you paid the fee as set forth in paragraph 1.E.8.

1.B. “Project Gutenberg” is a registered trademark. It may only be used on or associated in any way with an electronic work by people who agree to be bound by the terms of this agreement. There are a few things that you can do with most Project Gutenberg electronic works even without complying with the full terms of this agreement. See paragraph 1.C below. There are a lot of things you can do with Project Gutenberg electronic works if you follow the terms of this agreement and help preserve free future access to Project Gutenberg electronic works. See paragraph 1.E below.

1.C. The Project Gutenberg Literary Archive Foundation (“the Foundation” or PGLAF), owns a compilation copyright in the collection of Project Gutenberg electronic works. Nearly all the individual works in the collection are in the public domain in the United States. If an individual work is unprotected by copyright law in the United States and you are located in the United States, we do not claim a right to prevent you from copying, distributing, performing, displaying or creating derivative works based on the work as long as all references to Project Gutenberg are removed. Of course, we hope that you will support the Project Gutenberg mission of promoting free access to electronic works by freely sharing Project Gutenberg works in compliance with the terms of this agreement for keeping the Project Gutenberg name associated with the work. You can easily comply with the terms of this agreement by keeping this work in the same format with its attached full Project Gutenberg License when you share it without charge with others.

1.D. The copyright laws of the place where you are located also govern what you can do with this work. Copyright laws in most countries are in a constant state of change. If you are outside the United States, check the laws of your country in addition to the terms of this agreement before downloading, copying, displaying, performing, distributing or creating derivative works based on this work or any other Project Gutenberg work. The Foundation makes no representations concerning the copyright status of any work in any country other than the United States.

1.E. Unless you have removed all references to Project Gutenberg:

1.E.1. The following sentence, with active links to, or other immediate access to, the full Project Gutenberg License must appear prominently whenever any copy of a Project Gutenberg work (any work on which the phrase “Project Gutenberg” appears, or with which the phrase “Project Gutenberg” is associated) is accessed, displayed, performed, viewed, copied or distributed:

This eBook is for the use of anyone anywhere in the United States and most other parts of the world at no cost and with almost no restrictions whatsoever. You may copy it, give it away or re-use it under the terms of the Project Gutenberg™ License included with this eBook or online at www.gutenberg.org. If you are not located in the United States, you will have to check the laws of the country where you are located before using this eBook.

1.E.2. If an individual Project Gutenberg electronic work is derived from texts not protected by U.S. copyright law (does not contain a notice indicating that it is posted with permission of the copyright holder), the work can be copied and distributed to anyone in the United States without paying any fees or charges. If you are redistributing or providing access to a work with the phrase “Project Gutenberg” associated with or appearing on the work, you must comply either with the requirements of paragraphs 1.E.1 through 1.E.7 or obtain permission for the use of the work and the Project Gutenberg trademark as set forth in paragraphs 1.E.8 or 1.E.9.

1.E.3. If an individual Project Gutenberg electronic work is posted with the permission of the copyright holder, your use and distribution must comply with both paragraphs 1.E.1 through 1.E.7 and any additional terms imposed by the copyright holder. Additional terms will be linked to the Project Gutenberg License for all works posted with the permission of the copyright holder found at the beginning of this work.

1.E.4. Do not unlink or detach or remove the full Project Gutenberg License terms from this work, or any files containing a part of this work or any other work associated with Project Gutenberg.

1.E.5. Do not copy, display, perform, distribute or redistribute this electronic work, or any part of this electronic work, without prominently displaying the sentence set forth in paragraph 1.E.1 with active links or immediate access to the full terms of the Project Gutenberg License.

1.E.6. You may convert to and distribute this work in any binary, compressed, marked up, nonproprietary or proprietary form, including any word processing or hypertext form. However, if you provide access to or distribute copies of a Project Gutenberg work in a format other than “Plain Vanilla ASCII” or other format used in the official version posted on the official Project Gutenberg website (www.gutenberg.org), you must, at no additional cost, fee or expense to the user, provide a copy, a means of exporting a copy, or a means of obtaining a copy upon request, of the work in its original “Plain Vanilla ASCII” or other form. Any alternate format must include the full Project Gutenberg License as specified in paragraph 1.E.1.

1.E.7. Do not charge a fee for access to, viewing, displaying, performing, copying or distributing any Project Gutenberg works unless you comply with paragraph 1.E.8 or 1.E.9.

1.E.8. You may charge a reasonable fee for copies of or providing access to or distributing Project Gutenberg electronic works provided that:

- • You pay a royalty fee of 20% of the gross profits you derive from the use of Project Gutenberg works calculated using the method you already use to calculate your applicable taxes. The fee is owed to the owner of the Project Gutenberg trademark, but he has agreed to donate royalties under this paragraph to the Project Gutenberg Literary Archive Foundation. Royalty payments must be paid within 60 days following each date on which you prepare (or are legally required to prepare) your periodic tax returns. Royalty payments should be clearly marked as such and sent to the Project Gutenberg Literary Archive Foundation at the address specified in Section 4, “Information about donations to the Project Gutenberg Literary Archive Foundation.”

- • You provide a full refund of any money paid by a user who notifies you in writing (or by e-mail) within 30 days of receipt that s/he does not agree to the terms of the full Project Gutenberg™ License. You must require such a user to return or destroy all copies of the works possessed in a physical medium and discontinue all use of and all access to other copies of Project Gutenberg™ works.

- • You provide, in accordance with paragraph 1.F.3, a full refund of any money paid for a work or a replacement copy, if a defect in the electronic work is discovered and reported to you within 90 days of receipt of the work.

- • You comply with all other terms of this agreement for free distribution of Project Gutenberg™ works.

1.E.9. If you wish to charge a fee or distribute a Project Gutenberg™ electronic work or group of works on different terms than are set forth in this agreement, you must obtain permission in writing from the Project Gutenberg Literary Archive Foundation, the manager of the Project Gutenberg™ trademark. Contact the Foundation as set forth in Section 3 below.

1.F.

1.F.1. Project Gutenberg volunteers and employees expend considerable effort to identify, do copyright research on, transcribe and proofread works not protected by U.S. copyright law in creating the Project Gutenberg™ collection. Despite these efforts, Project Gutenberg™ electronic works, and the medium on which they may be stored, may contain “Defects,” such as, but not limited to, incomplete, inaccurate or corrupt data, transcription errors, a copyright or other intellectual property infringement, a defective or damaged disk or other medium, a computer virus, or computer codes that damage or cannot be read by your equipment.

1.F.2. LIMITED WARRANTY, DISCLAIMER OF DAMAGES - Except for the “Right of Replacement or Refund” described in paragraph 1.F.3, the Project Gutenberg Literary Archive Foundation, the owner of the Project Gutenberg™ trademark, and any other party distributing a Project Gutenberg™ electronic work under this agreement, disclaim all liability to you for damages, costs and expenses, including legal fees. YOU AGREE THAT YOU HAVE NO REMEDIES FOR NEGLIGENCE, STRICT LIABILITY, BREACH OF WARRANTY OR BREACH OF CONTRACT EXCEPT THOSE PROVIDED IN PARAGRAPH 1.F.3. YOU AGREE THAT THE FOUNDATION, THE TRADEMARK OWNER, AND ANY DISTRIBUTOR UNDER THIS AGREEMENT WILL NOT BE LIABLE TO YOU FOR ACTUAL, DIRECT, INDIRECT, CONSEQUENTIAL, PUNITIVE OR INCIDENTAL DAMAGES EVEN IF YOU GIVE NOTICE OF THE POSSIBILITY OF SUCH DAMAGE.

1.F.3. LIMITED RIGHT OF REPLACEMENT OR REFUND - If you discover a defect in this electronic work within 90 days of receiving it, you can receive a refund of the money (if any) you paid for it by sending a written explanation to the person you received the work from. If you received the work on a physical medium, you must return the medium with your written explanation. The person or entity that provided you with the defective work may elect to provide a replacement copy in lieu of a refund. If you received the work electronically, the person or entity providing it to you may choose to give you a second opportunity to receive the work electronically in lieu of a refund. If the second copy is also defective, you may demand a refund in writing without further opportunities to fix the problem.

1.F.4. Except for the limited right of replacement or refund set forth in paragraph 1.F.3, this work is provided to you ‘AS-IS’, WITH NO OTHER WARRANTIES OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO WARRANTIES OF MERCHANTABILITY OR FITNESS FOR ANY PURPOSE.

1.F.5. Some states do not allow disclaimers of certain implied warranties or the exclusion or limitation of certain types of damages. If any disclaimer or limitation set forth in this agreement violates the law of the state applicable to this agreement, the agreement shall be interpreted to make the maximum disclaimer or limitation permitted by the applicable state law. The invalidity or unenforceability of any provision of this agreement shall not void the remaining provisions.

1.F.6. INDEMNITY - You agree to indemnify and hold the Foundation, the trademark owner, any agent or employee of the Foundation, anyone providing copies of Project Gutenberg™ electronic works in accordance with this agreement, and any volunteers associated with the production, promotion and distribution of Project Gutenberg™ electronic works, harmless from all liability, costs and expenses, including legal fees, that arise directly or indirectly from any of the following which you do or cause to occur: (a) distribution of this or any Project Gutenberg work, (b) alteration, modification, or additions or deletions to any Project Gutenberg work, and (c) any Defect you cause.

Section 2. Information about the Mission of Project Gutenberg

Project Gutenberg is synonymous with the free distribution of electronic works in formats readable by the widest variety of computers including obsolete, old, middle-aged and new computers. It exists because of the efforts of hundreds of volunteers and donations from people in all walks of life.

Volunteers and financial support to provide volunteers with the assistance they need are critical to reaching Project Gutenberg’s goals and ensuring that the Project Gutenberg collection will remain freely available for generations to come. In 2001, the Project Gutenberg Literary Archive Foundation was created to provide a secure and permanent future for Project Gutenberg and future generations. To learn more about the Project Gutenberg Literary Archive Foundation and how your efforts and donations can help, see Sections 3 and 4 and the Foundation information page at www.gutenberg.org.

Section 3. Information about the Project Gutenberg Literary Archive Foundation

The Project Gutenberg Literary Archive Foundation is a non-profit 501(c)(3) educational corporation organized under the laws of the state of Mississippi and granted tax exempt status by the Internal Revenue Service. The Foundation’s EIN or federal tax identification number is 64-6221541. Contributions to the Project Gutenberg Literary Archive Foundation are tax deductible to the full extent permitted by U.S. federal laws and your state’s laws.

The Foundation’s business office is located at 41 Watchung Plaza #516, Montclair NJ 07042, USA, +1 (862) 621-9288. Email contact links and up to date contact information can be found at the Foundation’s website and official page at www.gutenberg.org/contact

Section 4. Information about Donations to the Project Gutenberg Literary Archive Foundation

Project Gutenberg™ depends upon and cannot survive without widespread public support and donations to carry out its mission of increasing the number of public domain and licensed works that can be freely distributed in machine-readable form accessible by the widest array of equipment including outdated equipment. Many small donations ($1 to $5,000) are particularly important to maintaining tax exempt status with the IRS.

The Foundation is committed to complying with the laws regulating charities and charitable donations in all 50 states of the United States. Compliance requirements are not uniform and it takes a considerable effort, much paperwork and many fees to meet and keep up with these requirements. We do not solicit donations in locations where we have not received written confirmation of compliance. To SEND DONATIONS or determine the status of compliance for any particular state visit www.gutenberg.org/donate.

While we cannot and do not solicit contributions from states where we have not met the solicitation requirements, we know of no prohibition against accepting unsolicited donations from donors in such states who approach us with offers to donate.

International donations are gratefully accepted, but we cannot make any statements concerning tax treatment of donations received from outside the United States. U.S. laws alone swamp our small staff.

Please check the Project Gutenberg web pages for current donation methods and addresses. Donations are accepted in a number of other ways including checks, online payments and credit card donations. To donate, please visit: www.gutenberg.org/donate.

Section 5. General Information About Project Gutenberg electronic works

Professor Michael S. Hart was the originator of the Project Gutenberg concept of a library of electronic works that could be freely shared with anyone. For forty years, he produced and distributed Project Gutenberg eBooks with only a loose network of volunteer support.

Project Gutenberg eBooks are often created from several printed editions, all of which are confirmed as not protected by copyright in the U.S. unless a copyright notice is included. Thus, we do not necessarily keep eBooks in compliance with any particular paper edition.

Most people start at our website which has the main PG search facility: www.gutenberg.org.

This website includes information about Project Gutenberg, including how to make donations to the Project Gutenberg Literary Archive Foundation, how to help produce our new eBooks, and how to subscribe to our email newsletter to hear about new eBooks.

Table of Contents

- WIRELESS POSSIBILITIES
- PREFACE
- INVENTION
- THE IMPORTANCE OF SOUND IN WIRELESS
- WIRELESS INACCURACIES
- RADIO TELEVISION
- WIRELESS AND WAR
- THE FULL PROJECT GUTENBERG™ LICENSE