"Oh, it isn't the wireless part I object to," drawled His Highness. "It is that dot and dash code that gets me. I never could learn it if I tried ten years; and as for taking twenty words a minute in any language—well, they could have the whole outfit before I'd do it."
"I shall be interested to see what speed I can make," mused Dick.
"Speed! You won't make any speed at all—at least not at first, so do not hope or expect to. If you even get the words correctly you will be going some," sniffed Walter. "Still, I guess you need not worry for the present about receiving or sending messages for Bob will give you a lot to think about before that. As for the Morse code, you may not meet it for weeks."
"What do you mean?" Dick inquired.
"Oh, Bob will get right down to brass tacks at the start and find out what you know about electricity and wireless anyway. That is the way he did to me when he tutored me in Latin. He wasn't content with just translating Caesar but must needs splash right into Roman history and make me hunt up everything I could find about the Goths and the rest of those heathen tribes. Gee, but he made me sweat! He will do that with you and your wireless. If you think you are going to begin taking messages in code you don't know Bob."
Having delivered himself of these brotherly appreciations His Highness walked away, leaving Dick to ponder on the joyous prospects they contained. His sinister prediction Richard Crowninshield soon found to be true. Thorough was no name for Bob King. Before a week had passed Dick whimsically remarked to his father that it must be a task to Bob to swim on the top of the sea without diving down with a spy glass and examining every particle that was on the ocean's bottom. The fact that the new tutor never dipped into any subject but instead explored it greatly delighted Mr. Crowninshield.
"I shouldn't mind letting that young chap tutor me a little," observed he half jestingly to his wife. "I am as vague as a fog when it comes to this wireless business. I should get a lot of information if I listened in on Dick's lessons."
The words, idly spoken, much to the amusement of all became a reality. After drifting in to the first talk Mr. Crowninshield came to the second lesson and from then on he became a regular pupil.
"You needn't be afraid I have come here to criticize," explained he with appealing simplicity. "I'm green as grass and have come to learn."
"It is just that you have not had the time to take up radio, sir," was Bob's modest answer. "We all have our specialties."
"That's right," agreed the capitalist. "Sometimes I fall to wondering whether it is better to know something about everything or everything about something."
"To know something about everything would be spreading it pretty thin, I am afraid," was Bob's characteristic reply.
"That wouldn't do for you, eh?" remarked Mr. Crowninshield with a chuckle.
"It would not satisfy me; no, sir. As it is I cannot begin to master what there is to be known concerning this one branch of science. Were my head to be filled with a little of everything I should feel as if it were a grab bag."
"Many heads are," was the laughing retort. "Still, with each successive generation rolling up its accumulation of knowledge the intellectual snowball is getting to be of ponderous size. History's remedy for this malady has always been to knock the whole structure to pieces every now and then and begin again. Perhaps we shall have to have another period of the Dark Ages and another Renaissance to set us right."
Thoughtfully he puffed his cigar.
"This wireless now—think of the new fields it has opened up. Not only are our ships equipped so that they can send and receive all sorts of messages, get their location, be informed concerning harbor entrances and coast lines; set their compasses and clocks but soon wireless telephones will be installed in the staterooms of all passenger steamers so that those crossing the ocean can talk with their friends ashore any time they may elect to do so. Of course there are times when such a thing might have its advantages; but for tired people—doctors and the like—who are trying to get to a spot where they cannot be reached by business cares it will be a negative sort of blessing. I, myself, for example, always count on my stay on shipboard as a sort of vacation, an interval when nobody can bother me with office matters. But if in future I must have a wireless telephone at my bedside I shall be no more isolated than I should have been had I remained at home. Pretty soon there will be no place under the sun where a man can go and get peace and quiet. The Maine woods will be full of radio outfits and the tops of distant mountains in touch with the stock market. Even an aeroplane carries its wireless. It is hideous to contemplate!" he sighed. "As for city life, we shall be beset wherever we go. And if the fashion set by some of our city police of having wires tucked away in uniforms and a wireless receiver carried in the pocket prevails in due time even when we walk the streets we shall all be in constant touch with our particular headquarters."
At his rueful expression Bob could not but laugh.
"There certainly is no question that a great day for wireless is coming," replied he. "Whether we like it or not the thing has come to stay and as yet we have only half discovered what can be done with it. It is undoubtedly rough on those who want isolation. But most people don't. They are glad to feel, for instance, that the ocean is so small they can talk with their friends while they are crossing it. Besides, you must not forget how much good ship surgeons and doctors can now do for those who otherwise would have no aid at hand. Remote lighthouses and small ships that need medical service often signal the big liners now and ask advice of the ship's doctor. I heard a little while ago of a lighthouse keeper whose leg was amputated under the wireless direction of one of our great surgeons. Had instructions not been available the man would probably have died of blood poison. And many times there is sickness aboard small vessels that are out to sea. They signal the symptoms of their patients and the doctor hundreds of miles away replies with a remedy. As all boats carry medicine chests the distant physician can easily designate what dose to give."
"That is a fine idea!" nodded Mr. Crowninshield. "I hadn't thought of treating illness by radio. A bit tough on the doctor, though. It must keep him busy."
"I am afraid it does. In fact some of the ship's surgeons are demanding higher pay because of the rush of work put on them. To have the health of a large ship under one's supervision is task enough without treating all the people sailing the ocean. They say some doctors are all in after a trip simply because of the extra calls that pour in from outside ships and stations. It keeps them hopping day and night, for of course no decent doctor will ever refuse aid to those who are suffering."
"Humph! That is quite a new phase of wireless."
"It proves it can save life not only at a time of shipwreck but in other crises as well," Bob responded with enthusiasm. "Now all that remains is for some clever fellow to come along who shall find a remedy for the difficulties that baffle the radio man. Then the science will come into its own. We must get rid of static interference—our greatest bugbear."
"Come, come, son! You must not spring any of your technical terms on me. Remember that while I am old in years I am still young in radio knowledge. Before you go slipping those phrases jauntily off your tongue you have got to begin at the very beginning and tell us the laws on which the radio telephone is based."
"That is a rather big order, sir," Bob replied modestly. "However, I am willing to try to fill it. I can at least pass on to you all that I know myself."
"That will satisfy me," affirmed the capitalist. "I see no reason, either, why your young brother cannot arrange his work so that he can join our class. The more the merrier. I even propose to drag in my wife and daughter. If in future we are to have wireless apparatus wherever we go it will be unintelligent not to know something about it."
"I am afraid it is going to pursue us pretty much to every corner of the earth," smiled Bob gravely. "You see, one of its great advantages is that it can go where the telephone with its myriad wires and poles cannot. It would be out of the question, for example, to string telephone wires through densely wooded sections and to the tops of high mountains, and even if the impossible could be accomplished the expense of keeping such lines in proper repair would be so great that no one could afford to shoulder it. Poles rot and wires rust out with wear and exposure to weather. Then there is the damage from gales, ice-storms, and falling timber. Even under the best of conditions linemen would be kept busy all the time repairing the equipment. And as if these difficulties were not great enough in times of peace think of the added burden of protecting miles and miles of telephone wires in time of war. Contrast with this the small district to be protected when it comes to a wireless station. Instead of having soldiers scattered through miles of territory the few needed can be concentrated within easy reach of provisions and reinforcements. And the same advantages that the radio telephone has on land prevail as well at sea for transmission of messages by cable is a frightfully expensive thing. Not only is the laying of such a line difficult, dangerous, and costly, but to maintain it is expensive and hard as well. In time of war it is particularly at a disadvantage since the cable can be cut and all communication with the outside world easily severed. Wireless, on the other hand, is not dependent on any such extravagant equipment. It finds its own way through air, water, and earth with very little help from us; and if it has its defects we must not forget that the first telephones were far from perfect, and that both telephone and cable have also their disadvantages."
Top
During the interval when the new radio station was being put in order and the parts of the outfit assembled Bob King and the two city electricians toiled early and late. They scarcely stopped to eat, so feverish was their haste. Mr. Crowninshield had let it be known that if the wireless apparatus was in condition to send and receive messages within a week he would add to the regular wages of the mechanics a generous bonus and this incentive was sufficient to cause the avaricious workmen to transgress the laws of the labor unions and forget any fatigue they may have experienced.
As for Bob he was far too eager to get into touch with O'Connel and theSirento covet extra pay for rushing through the installment of the new service. A private signal had been agreed upon between him and his former associate and also an hour set when each day the operator aboard the yacht was to call him. O'Connel was to allow seven days for the work at Surfside to be finished and then his messages were to begin and both Mr. Crowninshield and his alert employee meant to be ready for him.
Hence Bob whipped on his helpers, using every ray of daylight that could be turned to the purpose and much of the night. Even after everything was placed and connected up there would yet remain a great deal of testing out and tinkering before the set would be in perfect working condition and it was for this delay he was preparing.
Much to his surprise, however, the parts went together with astonishingly little trouble. They had been well made and fitted perfectly. Everything needed was at hand and in consequence there was no sending to the city for materials and waiting until they could be shipped. Therefore as the allotted time sped by the job that accompanied it moved rapidly to its end.
"We are going to make it, sir," ejaculated Bob with shining eyes, beaming enthusiastically on the master of the estate. "She will be all set up and working by Saturday. That is the day O'Connel was to make his first try to get into communication with us. I can hardly wait to hear what he has to say."
"I am pretty anxious to know myself," returned the elder man. "If he can get a message through we should then find out where the yacht is and whether Lola is aboard her."
"I'm crazy to learn what has become of the villains who pinched the dog," added Bob. "Do you take it they are still cruising with the boat?"
"Oh, they must have been paid off and landed somewhere," was the answer. "There would be no sense in detaining the thieves on the ship until now. It would only mean paying them and having them to feed; besides one does not care to make two rascals members of a house party."
"You think they have escaped us then."
"If by escaping you mean getting to the city yes," nodded Mr. Crowninshield. "But I do not feel at all sure with Dacie and Lyman on their track that they will be entirely safe and unmolested in town. Those detectives are like bloodhounds and will run them down no matter where they may be hiding. The mere fact that they have got to New York or Boston will not be much protection."
"You intend to get them then as well as to recover Lola."
"I certainly do," retorted Mr. Crowninshield with emphasis. "I am going to recover my property, jail the thieves, and bring the people who received the stolen goods to justice."
"They have a week's start of us," Bob observed doubtfully.
"But we have not been idle all that time, man, Dacie and Lyman have been working; O'Connel has been using his eyes and ears—I hope; and we have this wireless set up."
"Yes, we have certainly accomplished something," admitted Bob.
"Accomplished something! I should say we had! Besides, this is not the sort of case one need hurry on. Nothing is going to be done suddenly," explained the financier. "Having got the dog the people on the yacht will move at their leisure. They do not fear that any one is at their heels chasing them up. Furthermore the sea offers unending concealment for their crime should they be pursued and trapped. It is the thieves themselves who are the scapegoats and the ones in danger, according to their reckoning."
"I suppose so," agreed Bob. "Still, I cannot help wishing we might have got after them without even these few days intervening."
"You forget, my son, that our wireless is going to cover space so quickly that hereafter we shall have our information very quickly and shall be exactly as well off as most detectives used to be in double the time."
"Yes, that is so."
"Once we are in touch with O'Connel we can know every thought they think aboard theSirenas soon as they have thought it."
The uncertainties that clouded the younger man's face vanished.
"That's right," smiled he. "From now on we should be able to checkmate them pretty neatly."
Mr. Crowninshield put his finger to his lips significantly. The two city electricians were approaching.
"Well, sir," began the foreman, "I guess your wireless tests out pretty near right; we've signalled our home company and got a reply from New York clear as a bell. With this chap at hand," he motioned to Bob, "you won't be needing us much longer, I reckon."
"Have you got to rush back to another job?" questioned the financier.
"Well, there is always plenty to do," grinned the man good-humoredly.
"You couldn't remain over a few days and overhaul my yacht, could you? She is anchored out in the bay close at hand. If you could be tightening things aboard her and seeing everything is right I would keep this young man at this shore station."
"Why—" the mechanic hesitated, fingering the roll of bills that stuffed his pocket. "Why," repeated he, "I imagine we could fix things up with the boss and stick round until whatever you wanted done was completed, sir."
"Arrange it then. Get the yacht into condition quickly so we can put to sea any day now that we choose."
"We'll do that, Mr. Crowninshield," responded the men in chorus. "Unless there is a lot to do to the outfit—"
"There isn't. It was all new in the fall; and we have been in Florida this winter too, so the ship has been in commission and constantly taken care of."
"In that case there will probably be little repairing," nodded the spokesman. "Maybe tightening and oiling, and a few small parts to be replaced."
"That is about it."
"Couldn't I—" Bob began but Mr. Crowninshield held up a cautioning finger.
"I'd rather have you on shore," announced he quietly. Then turning to the electricians he added, "I suppose the radio aboard the yacht does not differ much from this set. There will be nothing but what you can handle."
"Nothing, sir; nothing at all," was the answer. "Besides, we are quite familiar with shipboard equipment. We do a lot of such work. Just before we came down here we went down to Long Island and put theSiren, a very fine steam yacht, into shape."
"TheSiren, eh?" repeated Mr. Crowninshield as indifferently as he could.
"Yes, sir. Perhaps you know the boat, sir."
"I've never been aboard her," replied the capitalist slowly. "She belongs to——"
"To Mr. Daly, sir. As fine a yacht as was ever in the water."
Daly! At the name both Bob and his employer started. It was the very man Mr. Crowninshield had suspected.
"So Daly has a place down on Long Island, has he?" drawled he.
"Oh, no, sir. Mr. Daly's place is on an island off the Maine coast. He had just put in at the Long Island port for some minor repairs. He said he was going to cruise a while this summer and wanted to be sure everything was shipshape before going to Maine. The mate told me they were waiting to pick up some people at Buzzard's Bay."
"Going to take the yacht through the Canal?"
"Yes."
"An interesting trip," observed Mr. Crowninshield slowly. "That Canal is quite a time saver for New Yorkers." He yawned and started to move away. Bob held his breath, waiting.
"I suppose you don't know where Daly was going for his cruise," inquired he over his shoulder.
"No, sir, I don't," was the response of the workman who seemed flattered at having aroused this degree of interest in his story. "I believe, though, that before they started they were to put into Newport for provisions."
Newport! Then it was doubtless Newport where O'Connel was to be taken aboard! Bob dared not raise his eyes lest the excitement that danced in them be detected.
"And after provisioning up there Daly was to cruise, eh?" called Mr. Crowninshield. "Well, the Atlantic is wide and he will have plenty of room."
"That's right, sir," chuckled the mechanic, delighted by the condescension of the great man whom all New Yorkers knew by reputation. Think of hobnobbing in this pleasant fashion with one of the big financiers of Wall Street!
"How simple and kind a gentleman Mr. Crowninshield is!" commented he patronizingly after the capitalist was out of hearing. "And so artless!"
Bob struggled not to smile.
Kind Mr. Crowninshield might be but hardly simple. Certainly not artless. What a rare lot of amusing incidents the world contained!
Top
The wireless was now in commission and the next morning, after having waited until the hour designated for O'Connel's signal and received no message, Bob and his pupils assembled for their first lesson, not in a stuffy room but on the broad, well-shaded veranda of Surfside. A cool breeze rippled the water, stirring it into tiny waves and as Dick dropped into one of the big wicker chairs he fidgeted to be out in the freshly-painted knockabout that bobbed invitingly at the float.
His father intercepted his yearning glance and instantly interpreted it.
"Come, now!" said he half playfully. "Quit making sheep's eyes at that boat, son. An hour's wireless lesson isn't going to cut your morning very short or prevent you from having plenty of time to sail, swim, or motor. Whether it does or not you've got to endure it. Your summer holiday is long enough in all conscience. If I had until October with nothing more arduous to do than put up with an hour's instruction early each day I should think myself almighty lucky."
"I am lucky, Dad," conceded Dick quickly, "only——"
"Lucky! I should say you were! You don't know what work means. Well, it was you who wanted this radio outfit. You were all for it and——"
"I am for it still, Dad," interrupted Dick eagerly.
"Then go to it and master it," retorted his father. "If you do not relish the lessons swallow them down for the sake of the fun you are going to have later; for if you are intelligent enough to handle your wireless with some brain and understanding you are going to enjoy it a hundred per cent. more in the end."
"I know I shall," Dick agreed. "It is only that I am crazy to get at the thing itself."
The boy's father shook his head.
"You are like all your generation," said he severely. "Eager to leap the preliminaries and land at the top of the ladder with the first bound. It is an impatient age and the vice extends to the old as well as the young. Nobody wants to fit himself for anything nowadays. In my youth men expected to serve apprenticeships and did not hope to achieve a position until they had learned how to fill it. But now everybody leaps at the big job and the big salary that goes with it and blunders along, taking out his ignorance and lack of experience on the general public. As for you youngsters, you covet at fifteen everything that those who are fifty have. You want automobiles, boats, victrolas and radio telephones before you know how to run them, much less pay for them. Look at Bob, here. He is worth two of you for he can earn what he has. Often I tell myself I am a fool to indulge you and Nancy as I do. I ought by rights to make you do without what you want until you can foot the bill for it." Mr. Crowninshield took a few hasty paces across the piazza. "Still," added he, his voice softening, "I fancy that scheme would be a sight harder on me than on you, for I like nothing better than to get you what you want."
For a moment he paused, looking fondly at his son. Then as if afraid of himself he bristled and continued: "But to return to this wireless—remember that if you do not learn something about it and how to use it I shall take it away. I mean it, mind!"
"Yes, Dad," was the timid answer.
With this awful alternative looming like a specter in his path was it to be wondered at that Dick resolutely turned his gaze from the allurements of the harbor and settled himself in the big chair with all his attention focussed on Bob King's radio lesson. Moreover, human nature is selfish enough to like company in its misery and were not his mother, Nancy and Walter consigned to the same fate as himself?
Therefore the initial lesson began gayly.
At first Bob, seated in the chair of state facing his class, was shy and embarrassed; but soon he forgot himself in his subject and losing his hesitancy he spoke with the authority of one who has mastered his art.
"I am going to begin," said he, "just as they began with me at the radio station for I think if you get the principles of wireless at the outset you will find it much easier to understand it. And to do this we shall not start with wires, generators, detectors, or anything of that sort; instead we must go back of them all to the earth and the air, and learn how it is possible for sound to travel without the aid of human devices. For in reality there is something that takes the place of man-made wires. This is the ether. Surrounding the earth moves the air we breathe; and as we go higher this air becomes thinner and thinner until, by and by, a height is reached where the air gives place to ether, a sort of radiant energy that bridges the zone between the air space that encircles the earth and the sun, and brings to us its heat. This great sea of ether is made up of particles that are never still and which are so small that they get between every substance they encounter, thereby becoming a universal medium for transmitting light, heat, color and many other things to our earth. Without this body of ether, there would be no agency to pass on to us (as well as to the many other planets of our solar system and those outside it) the energy the sun generates, which is the thing that keeps us alive."
Bob waited a moment to make sure that his point was clear and then proceeded:
"Now this energy as it moves through the ether takes the form of waves; and these waves go out not in a single train but since the ether is continually disturbed by the sun, in series of wave trains that vary in frequency. Such waves are electromagnetic in character, and light, heat, sound, and the waves carrying wireless messages are all of a similar type, differing only in their relative rates of vibration. If unobstructed, and moving through free ether, all of them travel at practically the same velocity, that is about one hundred eighty-six thousand miles a second. When, however, they encounter other substances, as they are continually bound to do, this rate of velocity changes. The waves of sound, for example, sent out by the wireless telephone are very slow compared with the high-rate vibrations that produce waves resulting in light."
Again the youthful teacher paused.
"Now this constant turmoil in the ether which creates the magnetic area explains why the magnetized needle of a compass unfailingly points north and south. This one simple fact is a certain proof of its existence. And once granting a magnetic field to be there it is less difficult to understand how wireless waves are produced in this congenial medium and find their way through it, following in their journey the curve of the earth's surface."
Bob smiled at his audience encouragingly.
"If you can once get this wave law through your heads the rest is not hard," asserted he, "for the whole wireless system is based on wave motion."
"With an ocean spread out before us we ought to be able to understand waves," interpolated Nancy.
"We ought," nodded Bob. "And yet better than using the ocean as an illustration imagine a small pond. Think, instead, of a nice quiet little round pond if you can. Now when you chuck a stick or a pebble into that still water you know how the ripples will at once go out. There will be rings of them, and the bigger they get the fainter they will be. In other words, as the area widens the strength of the waves decreases; and as this same principle applies to radio you can see that it takes a lot of energy from a wireless station to reach a receiver a great distance away."
"I've got that!" cried Dick with such spontaneity that every one laughed.
"Wave lengths, however, have nothing to do with actual distance," went on Bob quickly. "Of course we think of the wave length as the distance between one ridge of water and another. There is, though, no law that would make it possible to translate these spaces into our scale of miles, for sometimes they are near together, sometimes far apart. Distance, therefore, depends on the speed with which the wave travels and the frequency with which the water is disturbed. If you keep tossing things in quick succession into the water you will get a correspondingly quick succession of waves. The law governing wireless waves is exactly the same. Their length depends on the velocity of the wave and the frequency of the oscillations that cause it. Or to put it another way, in order to reckon a wave length you must determine its velocity (which is not impossible when you remember that sound travels about one thousand one hundred and twenty feet every second) and the number of vibrations the particular note causing the wave is making per second. Now science has been able to compute just how many complete vibrations a certain note, key, or pitch as you may please to call it, makes each second, or how many times the particles of air vibrate back and forth when that especial note is sent out.
"Suppose, for example, a note makes 240 complete vibrations a second while traveling 1,120 feet; if we divide 1,120 by 240 we shall get 4.66 as the wave length of this note. So it is the pitch to which a note is keyed that helps determine its distance; and the force employed to start the note sent out through the magnetic field. That is why a message projected into the ether from a high-power station carries a greater distance than one sent from a station where the power is weaker. It is by power and pitch, then, not by length that we gauge wireless waves. Do you see that?"
A chorus of assent greeted the question.
"That's bully!" Bob announced boyishly; then blushed at the undignified ejaculation.
"Don't you be fussed, young man," smiled Mr. Crowninshield. "We're all of an age here."
"I quite forgot," apologized the tutor.
"That is exactly what I want you to do," returned the master of Surfside. "Ignore us old people. We are only listening in, anyway, and have no earthly right to be here."
"Still, I wish to treat you with——"
"It's all right, Bob. We understand," put in Mrs. Crowninshield reassuringly.
"Well, then, if you will excuse me I'm off again," replied the boy. "And now that we've got wave lengths settled to our satisfaction we must remember some other things. One is that sound travels not only through the air but through the water. In fact, sounds are louder under water than they are above it. Water is not only a better medium for carrying sound but also, since it contains fewer obstructions, sound waves travel farther through it. Another thing which we must not forget is that our ears do not hear all the sounds that go on about us. The merciful Lord has arranged that when there are less than twenty-four vibrations a second, or more than forty thousand they escape us. But a wireless instrument, on the contrary is spared nothing, having attached to it a detector that catches every sound and an amplifier that magnifies it and makes it discernible to our ears. When you listen in on a wireless telephone you will be uncontestably conscious of this. Also you must take into consideration that the waves sent out by a radio transmitter are not choppy, irregular ones such as you get when a stone is tossed into the water; wireless waves go out in regular, well-formed relays that neither overlap nor obscure one another. Were this not so the signals made would be jumbled together and utterly unintelligible."
"Sure they would!" Bob's young brother nodded.
"Now to insure these several results we are compelled to resort to the help of scientific apparatus. Therefore at every receiving station we have devices that will intercept the waves as they come in; retransform them into electrical oscillations; and catching the weak oscillations make them strong enough to be read. Hence we use some type of induction coil by means of which a battery current of such low pressure and diffused flow as scarcely to be felt will be transformed or concentrated into a pressure that is very powerful. In order to form wireless waves we must have a frequency of at least one hundred thousand vibrations a second; and as it is out of the question to produce these by mechanical means we employ a group of Leyden jars. Such jars you have of course seen. They have in them two pieces of tinfoil separated by glass, which is a nonconductor of electric currents, and various other acids and minerals. When you connect a number of these small jars together you have a battery as powerful as that of a large single jar."
"I never saw jars like those," objected Dick.
Bob beamed at the intelligence of the demurrer.
"When I say jar," explained he, "it does not necessarily mean that these jars are of the round, cylindrical shape that comes to mind when you mention the word; on the contrary Leyden jars are often flat because such a form makes them more compact. That is also why we use several little ones instead of one big one. But whatever their shape the principle involved is always the same. When the terminals are connected with a current the jar will not only receive but will retain a charge equal in pressure to that of the device sending the current. And when you go even farther and bring the terminals near together, the quick discharge that takes place creates an electric spark which is in reality a series of alternating flashes that come so fast as to be blurred into what appears to be one. Could we separate these flashes we should find that each of them lasts less than a thousandth part of a second. The frequency of such oscillations is regulated by what is technically termed capacity, that is the size of the Leyden jar. The smaller the capacity the greater the frequency of the flashes.
"Now this spark, or oscillatory discharge emitted from the Leyden jar, does not result from a single traveling of the current all in one direction; instead the electricity moves back and forth, or alternates, and the space where the discharge takes place (and which, by the way, can be lengthened or decreased as pleases the operator) is known as the spark gap."
"But I should think this explosion of the spark would make a noise," commented Walter.
"Bully for you, little brother!" returned Bob, smiling at His Highness. "You are quite an electrician. If the current is strong, or, in other words, if the discharge is a high frequency one, it does. Hence something has to be used to deaden the sound just as a muffler is used on a motor boat. It is important, however, that this muffler should not prevent the operator from watching the condition of his spark for otherwise he could not keep track of his battery or know whether it was on the job or not. So you will find little peepholes of mica or glass in the sides of the muffler."
"Windows," murmured Nancy grasping the idea and translating it into the vernacular.
"Exactly," Bob agreed. Evidently his audience were understanding what he was trying to make clear to them.
"Now we have our high frequency oscillations occurring in the spark discharged from the Leyden jar and jumping the spark gap; nevertheless they would not do us any good were there not some way to use and regulate them. This brings us to the induction coil of which I spoke a second ago."
"It sounds very terrible," smiled Mrs. Crowninshield.
"It isn't, though," answered Bob, returning the smile. "In fact it is a very simple device—nothing more than a dozen or so twists of copper wire reeled about a wooden frame exactly as strands of thread might be wound round a spool. One end of the inductance is connected permanently with the ground and from the other end two movable wires go out, one of which can be connected with the spark gap and the other with the antenna that goes into the air and catches the sound waves. There isn't anything very terrible about that, you see."
"Antenna is what butterflies have," suggested Nancy vaguely.
"Quite right!" assented the wireless man. "Only radio antennæ are not to feel with—at least not in the same way. Nevertheless they do reach out and capture the sound. On all wireless stations you will notice the masts that support them. Sometimes there is one wire, sometimes a group. It is the wires themselves, remember, not the masts, which are the antennæ. Nowadays, however, you will occasionally see an indoor aerial used in connection with small, low-power outfits. It does away with the masts and outside equipment and frequently serves the same purpose quite satisfactorily. But most persons prefer the older method and for long-distance work it has, up to date proved to be indispensable. Now the antenna has both electrical capacity and inductance, and when connected up with the apparatus a wireless operator can at will cause it to disturb the magnetic fields surrounding the earth."
"You didn't say how high these masts had to be, Bob," put in Mr. Crowninshield. "Are they always the same length?"
"Oh, no, indeed, sir," was the prompt response. "Their length varies according to the type of service required of them. I'm glad you asked the question. Sometimes the masts are about two hundred feet high; again they may approximate four hundred and eighteen feet. And sometimes in emergencies you will discover no masts at all, the wires being fastened instead to captive balloons or kites which hold them in place long enough to send or receive hasty messages. This latter method is usually resorted to in wartime or during army or navy maneuvers. There are also compact radio sets to be had that can be carried on mule-back and set up and taken down on a hurried army march. On shipboard the ordinary masts of the vessel serve, of course, to support the antenna."
"Thank you, Bob. That is exactly what I wanted to know," said Mr. Crowninshield.
"I'm glad, sir. Now you'd think by this time we had everything necessary to produce our wireless waves and yet we haven't. There is still one thing almost more important than all the rest that we have not yet spoken of."
"What's that, Bob?" piped Walter.
"The tuner. You recall that at the beginning I mentioned the pitch, note, or key of the sound produced or received?"
"Yes," returned the class in chorus.
"Well, it is in that tune or pitch, or whatever you prefer to call it, that a large measure of the secret of wireless lies. To be successful in getting and sending messages we must tune the oscillations, or key the signals caused by the discharge of the battery in our Leyden jar, so that they will be in harmony (or at precisely the same pitch) with the antenna circuit. That is, the parts of the instrument must synchronize, just as two persons who would talk together must speak in the same language. This adjustment is made in the inductance coil because although both the Leyden jar where the spark is generated that causes the oscillations and the antenna can be regulated independently of each other a few turns of the inductance coil affects each circuit. After the two circuits have been adjusted to the same frequency they are said to synchronize. Often to reach this result a device is used that states precisely the wave length, and after the frequency of one circuit has been ascertained the other can easily be adjusted to correspond with it. The length of the wave is, you see, dependent on the largeness of the antenna and the capacity, or strength of current, of the Leyden jar. Just as a child uses a big stone to produce the largest splash and greatest waves so we must have a powerful force behind our wave lengths to make them carry most successfully. In accordance with this law, generally speaking, we find short wave lengths used for low power, short-distance outfits; and long wave lengths for high-power circuits whose aim is to traverse continents and oceans."
Bob pushed back his chair.
"I think," said he, "we have now come to a good stopping place and we will call the lesson off for to-day. If you digest all I have told you, you will have had an ample radio starter."
"You haven't said much about sending messages," complained Dick.
"That is quite another story," smiled the boy's tutor, "and such a long one that were I to tell it to you now it would mean you would get no sailing or swimming to-day."
Instantly Dick was on his feet, Leyden jars and inductance coils forgotten.
"We'll cut it out then," he laughed. "Who is for a swim? I'll race any man to the bath-house!" And off he went at top speed.
Top
Two days later O'Connel's first signal came.
Bob was at his early morning task of oiling and tightening up his apparatus and cleaning it, and both Dick and Walter were hovering near, watching him and learning all they could concerning the proper care of the equipment. Having made everything shipshape the young radio operator slipped the double head receiver over his forehead and prepared to listen in for his customary interval. Suddenly the boys saw him start excitedly and motion them to stop talking. With face alight he was leaning forward eagerly. Then came the sharp click of the Morse code and after an interval with radiant face the elder lad wriggled out of his trappings.
"What is it? What is it?" cried his two companions, hardly able to contain their curiosity.
"It was O'Connel."
"What did he say? Is the dog there? Where was the yacht?"
Breathlessly the questions tumbled one over the other.
"TheSirenis anchored off Gloucester and bound north, probably to Bar Harbor. A dog they call Trixie, but which O'Connel thinks is Lola, is aboard the boat. The description we gave him seems to fit her. He says she isn't very well—won't eat and seems either homesick or seasick. Mr. Daly is quite worried about her."
"For goodness' sake don't tell Dad or Mother that. They'll have a fit," Dick cried. "Should Lola die I believe my father would shoot Daly down."
"But I've got to give him the message."
"You needn't repeat all of it, need you?"
"Oh, I think you ought to tell them," Walter put in. "They would rather know, I'm sure."
"Dad will storm fit to raise the dead."
"We can't help it," answered His Highness.
"I am of the kid's opinion," Bob replied slowly. "I think we should tell your father and mother the whole truth just as O'Connel has sent it."
"Prepare for a nice, pleasant tornado, then," said Dick, "for you will get it all right."
"I wish I could have talked with O'Connel," declared Bob thoughtfully. "I did all I dared. You see, until our license comes I am not expected to transmit messages from this station. We have to get from the government both an operator's license and a permit for the station; and although I put in the application promptly there is so much red tape about it that it seems as if the inspector would never show up. If I had been caught sending a message this morning without these blooming papers there would have been the deuce of a row. However, I took a chance because I felt the emergency demanded it, and because being one of Uncle Sam's own men he couldn't very well put up the kick that I was not competent to handle a wireless outfit. Still, I shan't dare do it again."
"Isn't there anything we can do to hustle up the inspector?" inquired Dick.
"I'm afraid not, son. Government inspectors are not a hurrying race," was Bob's whimsical reply. "However, I telephoned our local man yesterday and something may happen to-day. He and I used to be on quite good terms when he occasionally dropped in at Seaver Bay. I told him that if I could not get a station license pretty soon our whole outfit would be no good to us this season. He promised he would take up the matter at once. With that I had to be satisfied. Whether he does anything or not remains to be seen."
"I suppose O'Connel understands this difficulty, doesn't he?" mused Dick.
"Oh, he knows, all right, why I can't answer him. I've assured him that his tidings have come through and that is all he wants to know," Bob answered. "He has dealt with the government himself and is familiar with its deliberate habits. Besides, there really isn't much we can say."
"Maybe you think that," grinned Dick, "but wait until you tell Dad that Lola is sick and hear him sputter. You will believe then that there is quite a bit that can be said. And if you get my mother to add her comments you will have plenty to relay over the wire."
The prophecy was indeed true, as Bob King proved after he had raced across the grass and overtaken Mr. and Mrs. Crowninshield on a tour of inspection to the rose gardens.
"News, Bob?" questioned the capitalist, wheeling about to meet the flying figure. "What is it? Let us have it quickly."
Carefully the message was repeated.
"Off Gloucester, eh, and bound north? Humph! And they've re-christened the poor little pupsie Trixie! Hang them! O'Connel thinks she isn't well? Of course she isn't seasick. Lola has been out on our yacht a hundred times. The reason she won't eat is because she is lonesome—misses her home and family. The wretches! I wish I had Daly here! I'd wring his neck," blustered Mr. Crowninshield.
"Isn't there anything we can do, Archibald? We simply must get that dog back before she dies. Poor little Lola! She was such a dependent little creature. It is terrible, terrible!"
"There, there, my dear! Don't go all to pieces over it. Aren't we doing all we can? Do you want Daly to smell a rat and toss his stolen property into the sea? Dacie says to give him rope enough and in time he will hang himself, and I am inclined to think the advice wise. Still, that does not prevent me from wishing I could lay hands on Daly. I'd like nothing better than to thrash the life out of him."
"I suppose you will telephone the detective the news we've received," suggested Bob, in order to quell the rising storm and divert Mr. Crowninshield's attention.
"Yes, I'll get New York on the wire right away. It is as well Lyman and his pal should know Lola is sick and that they can't dally round forever."
"Shall you be back for the wireless lesson?" called Bob, uncertain whether to ask the question or not.
"Oh, sure! It won't help matters for us to sit around and wail the whole morning. We'll be on deck for your radio talk at the usual time."
"All right, sir."
True to their agreement, at the appointed hour both Mr. and Mrs. Crowninshield made their appearance on the piazza and joined the group of young people who awaited their coming. They had, as Bob expressed it, cooled off a bit and were no longer in such an agitated frame of mind; nevertheless anxiety had left its mark by keying the master's voice to a sharper note, and shadowing the lady's brow with a frown of annoyance.
"I suppose you let out on O'Connel, didn't you, after he got through talking this morning?" was the first remark of the owner of Surfside.
"I couldn't say more than a word. Our license hasn't come yet, you know."
"That's so, darn it! I never saw anything in all my born life with so many rules attached to it as this wireless business. It is one tangle of rules, rules, rules! You might as well be tied up in a net," fretted the man.
"There do seem to be a good many rules at first glance," returned Bob pleasantly. "However, when you examine them most of them are both necessary and wise. And after all when each radio operator knows in black and white what he can do and what he can't it is far simpler."
"I suppose so," grumbled Mr. Crowninshield.
"Besides, there are always slackers at every job," continued Bob. "Rules help to keep such persons up to the mark and prevent carelessness and accidents."
"Yes, I fancy that is so," came more graciously from the still irate gentleman.
"Then all stations are not alike. That compass station at Bell Reef, for example, that you were asking me about yesterday; the government lays out specific duties and makes special rules for such a station, as in fact it does for all radio stations. Some of these rules relate to the care of the place and the cleaning and general overhauling of apparatus at stated intervals. There are, you see, certain instruments which must be cleaned and readjusted every day; certain others every week, others every month, and some every six months. It simply means making sure that your outfit is in the pink of condition with every part functioning as it should. There are, of course, operators who would see that this was done anyway, rules or no rules; but like every other profession there might be men who, off on an isolated spot with no one to keep them up to the mark, would grow careless and slovenly. Too much depends on wireless stations to run the risk of errors through imperfections in the equipment."
"I can understand all that; but aren't there a score of other regulations?"
"You mean about what they shall and shall not do?"
"Yes."
"There certainly are. There have to be because we have several different types of land stations. Just as the shipboard stations have their special kinds of work so do those on shore. For example, there are two different classes of radio compass stations,—those that operate independently and are located with a view to giving good cross-bearings to vessels that are from fifty to a hundred miles out to sea; and those known as harbor stations which are governed by a central control station and designed to inform ships within thirty miles of the entrance to outer channels of their position. The function of each of these stations is, as you can see, quite different and therefore each of them is obliged to have its own set of rules."
"I never knew anything about radio compass stations before," announced Dick.
"That is because you never sailed the seas and had to call on one for aid," smiled Bob. "If you did you would be very thankful, I guess, that the government has so carefully provided some one to answer just the sort of question you wished answered. I try to remember this when I get hot under the collar because the license for our station does not arrive. Uncle Sam can't help it if his men are slow. The plan at the top is all right. There must be rules to govern wireless stations, be they governmental, commercial, or private; rules to regulate the wave lengths each may use; rules to make sure the operators who have charge of them know their job; and inspectors to make sure that every such rule is obeyed."
"Who has the big chore of following up all these people and making certain that they are conforming to the law?" questioned Mr. Crowninshield.
"The Department of Commerce issues the licenses for all private and commercial stations and sends its inspectors to keep an eye on whatever comes under their control. It is this department that will have jurisdiction over Surfside if the license is granted. Government radio stations on the other hand, not only the high-power class but the coastal stations and everything that pertains to their relations with commercial stations afloat or ashore, whether in the United States or in foreign lands are entirely under the control of the Director of Naval Communications of the Navy Department."
"I wish you'd tell us something more about compass stations," Dick said. "Were you ever stationed at one?"
"Yes, for a little while I was on an island off the coast," replied Bob. "But I did not like it very well and applied for a transfer."
"It must have been lonely as the dickens on an island; worse, even, than being at Seaver Bay. Why in goodness did they build the station there?"
"Why, you see, a compass station that operates independently as that one did is usually situated on a lightship or an island because that location is best suited to the sort of work it has to do."
"And that is?"
"To give ships their positions when they sing out to ask exactly where they are," replied Bob. "Since the station is fairly well out to sea itself, it is able to furnish excellent cross-bearings and set the vessel on her course in case she is off it. Ships have been known to miss their way, you know, especially in a fog; and if they have not missed it they are often very grateful to be assured they have not and that their own calculations were correct. So the rule is that an operator must always be listening in for at least three minutes at ten, twenty-five, forty, and fifty-five minutes past the hour and be ready to answer a Q T E when he hears it."
"What's a Q T E?" inquired both Dick and Walter simultaneously.
"Those particular letters mean:What is my true bearing?It takes less time to send the letters than to spell out the entire sentence and therefore a simple code which means the same in all languages is used. When such a call is received the operator replies: Q T S (meaning: Your true bearing is) and then follows it with the number of degrees from his radio post stated in words, and also the name of the station responding to the message. It is a general rule, by-the-by, that all numerals used in any wireless communication must be spelled out to make sure of their being perfectly understood."
"What a bother!" ejaculated Walter.
"It prevents mistakes, brother; and if it does that it is certainly worth the trouble."
"I suppose so," answered His Highness a trifle crestfallen.
"Then what do you say next?" interrupted Dick, who was much interested in the subject in hand.
"Well, after you have given the true bearing the ship wires: Q T F."
"And that means?"
"What is my position?"
"And you have to repeat those words before giving it just as you did before?" asked Dick.
"Always," nodded Bob. "Every question asked is always repeated by the operator answering it to make sure that each party fully understands what is being talked about. You can't risk having a ship complain: 'Oh, I thought those figures you sent me were so-and-so.' No, indeed. Everything must be so explicit that there will be no room for blunders. So after you have repeated the question you send the latitude and longitudein words."
"I guess there is sense in the rules after all," smiled Mrs. Crowninshield. "Thus far we have not discovered any which, on being examined, were not both reasonable and wise."
"That's the way I feel," Bob rejoined. "After being in radio work and seeing the opportunities there are for mistakes I have decided operators cannot be too careful. You see it is not like talking with a person face to face. Those you are communicating with are usually miles and miles away. Such stations as I have been telling you about are on the lookout for any six-hundred-meter calls and they answer in this tune. After communication with a ship is established, however, the tune shifts to seven hundred and fifty-six meters if a Navy vessel should be talking; if not, the six-hundred-meter wave length assigned is used. This leaves the shorter range waves to commercial vessels and greatly simplifies matters."
"That is a good rule, too," chimed in Mr. Crowninshield.
"And now about the harbor stations," suggested Dick.
The young tutor smiled.
"I had not intended to give you all this stuff this morning," protested he, "but since you are interested in it we may as well go on with the subject. The task of the harbor stations, then, is to listen both on a six-hundred-meter range, and one of nine hundred and fifty-two—the first wave length for commercial and the latter for Navy ship's calls. Then in response to inquiry the operator directs the vessel how to enter that particular harbor, stating just where the entrance buoys are and where the channel lies. If the man at the wheel is new to the port this aid is invaluable."
"Not much like the navigation of the old days, is it?" mused Mr. Crowninshield. "I should think such stations would put pilots out of business."
"They do to some extent," was the reply. "There are, however, always ships that cannot make a landing under their own steam, ships that have to be towed. So the pilots still find something to do."
"And are these harbor stations on islands too?" questioned Nancy.
"Many of them are. A small proportion of them, though, are in lighthouses. It all depends on which place has the more favorable location."
"But do not the land stations that send messages sometimes interfere with these stations?" queried Mr. Crowninshield.
"There are rules to preventthat," laughed Bob. "Of course the difference in wave length to which the various types of stations are limited solves a part of this difficulty. As I told you commercial stations have their own particular wave length and must stick to it; and private stations such as this one here have their range of two hundred meters in which to operate and are confined to not more than one kilowatt for sending messages. You cannot use more than this without special permission from the Secretary of Labor. Should you do so you are liable to a fine of one hundred dollars if your offense is deliberate; if, however, it is proved that your apparatus was out of adjustment and overreached itself you may get off with a twenty-five-dollar fine. In that case you must see at once that your radio error is corrected and your outfit set right."
"But sometimes along the coast aren't there big government stations belonging to the army or navy? I should think these, with their press of business, would butt in on the smaller ones and raise havoc with them," ventured Mr. Crowninshield.
"Where there are such mix-ups and private or commercial stations interfere with important government outfits the smaller ones are not allowed to send messages during the first fifteen minutes of each hour, such time being reserved for government business. The government, on the other hand, must respect the rights of the littler chap and use this particular interval for transmitting. In fact, when licenses are issued this condition is made with private owners and the station is so listed. Of course, however, should an S O S call come, all rules go by the boards and the distress call has the right of way in every case."
Mrs. Crowninshield, smiling mischievously, rose from her chair.
"There is an S O S coming in right now for a lemonade," said she, fanning herself with her filmy handkerchief. "Who will join me?"
A chorus of "I!" "I!" greeted the question.
She touched a bell.
"Bring lemonade for six, Emelie," said she. "Put in some slices of orange, some strawberries, and plenty of cracked ice. What a warm day it is! I am glad I am not out on some hot, sun-baked island answering radio calls."
"You probably would not be hot if you were on an island out to sea, my dear," her husband returned playfully. "However, I'll agree that this veranda is good enough for me on a July day."
The tinkling of ice cut short the conversation. Far away through the house its distant cadence sounded.
"The first and tallest lemonade must be for Bob," Nancy announced. "He has certainly earned it."