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WHERE THE EXPERIMENTS WITH THE MULTIPLEX TELEPHONE WERE CONDUCTED.

Signal Office Research Laboratory at the Bureau of Standards, Washington.

man ear.

method, by which it is practicable to frequency waves, suitably tuned, are send extra conversations by the wire. traveling along the telephone wires—not

At the bottom of the idea upon which in the wire itself, but in a layer of ether the invention is based lies the fact that surrounding it. They cannot be called the electro-magnetic rays which pass sound waves, because they are too rapid over a telephone wire are audible only to produce an impression upon the huwithin definite limits of frequency. If

Major Squier calls them the vibrations are fewer than sixteen to "ultra-sound vibrations." Nevertheless, the second, they transmit no impression each voice that speaks into the transto the human ear. On the other hand, if mitter affects these waves differently, they number more than 20,000 to the sec- and every spoken word is faithfully carond, the human auditory apparatus is ried by them. When, therefore, at the unable to respond to them, and so per- other end of the line, they are retransceives nothing In other words, our lated back into sound waves, the mesears are deaf to vibrations above 20,000 sage becomes audible to the listener. per second, and below sixteen vibrations. Instead of an ordinary direct current

To carry his messages, Major Squier through the wire itself, impulses are sent employs high-frequency waves, far along it in the shape of high-frequency above the limit of human hearing. Ob- waves which, as the inventor says, “don't taining them from a dynamo, he tunes get into the wire at all.” If it be asked them to various pitches, so that each how many "extra conversations” can be conversation carried on over the wire is put on the conductor, the only possible based upon a separate and particular answer is "several," because the pumber number of vibrations per second. Inas- must depend upon the diameter of the much as the talks are on different elec- wire and other conditions. trical tunes, they do not interfere with As the frequency of the electro-magone another in the least.

netic waves increases, their energy apIt will be understood, then, that high- pears to have a steady growing tendency to get out of the wire itself. The ordi- ceiving stations, which is the ordinary nary battery telephonic current is largely custom. a conduction current through metal, and The circuits are ordinary telephonic the ohmic resistance of the wire is one circuits, such as are now utilized in wire of the principal obstacles to long-distance telephony and telegraphy. “In fact,” telephoning. On the other hand, in wire- says the inventor, “the regular twistedless telegraphy, frequencies from 100,- pair paper-insulated lead-covered tele000 up to several millions per second are phone cable serves the purpose very well, used, and the energy is chiefly radiated the energy being conveyed principally in into the ether of space.

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ONE HUNDRED THOUSAND-CYCLE GENERATOR FOR ELECTRIC WAVES USED BY

MAJOR SQUIER IN HIS EXPERIMENTS.

the minute layer of ether separating the There is, however, an intermediate two metallic conductors. By this means range, in which the vibrations are from a most efficient system of high-fre20,000 to 100,000 per second, and where- quency telephony or telegraphy is mainin the electro-magnetic energy is still tained, and, at the same time, any intersufficiently linked to the wire to pre- ferences between neighboring circuits vent excessive radiation into the ether. · operated by the system are eliminated, The wire, while carrying but a small part so that many such circuits may be of the energy, nevertheless acts as an brought to the same switchboard without efficient guide for the high-frequency interfering effects.”

. waves. Accordingly, use is made of The inventor further says: “Since a these steered ether waves as a vehicle to plurality of high-frequency waves of difcarry telephonic or telegraphic messages. ferent frequencies may be impressed on

It will thus be seen that the new in- the same line, and since these may be sevention combines the principles of wire- lectively separated from each other by less telegraphy and telephony with those suitably tuned circuits, it is obvious that of telegraphy and telephony by wire. multiplex telephony is practicable. Also, Major Squier, in other words, has taken it has been found that these high-frethe apparatus and methods now used in quency waves may exist on the same line wireless communication, and has applied with ordinary battery telephonic currents them to the transmission of electro-mag- without in any way affecting them; and netic waves along metal conductors, thus thus the system may be applied to the accomplishing an enormous improve- usual telephonic circuit without 'cross ment in efficiency over the plan of em- talk' or other disturbances.” ploying antennæ at transmitting and re- Major Squier calls attention to the

a

fact that it is almost impossible to make they become visible to the eye. We an ordinary telephonic system work could actually see telegraphic messages, satisfactorily over any circuit that is con- instead of hearing them, if our eyes were nected with the ground. Lines with such suitably constructed. circuits are subject to serious difficulties, The waves used by Major Squier bechief among which are the strange noises long to the great unexplored region heard in the receiving instruments. The which lies above the limit of audicause of these noises, by the way, is not bility and below the limit of visibilvery well understood. But the new plan ity. They can be neither heard nor seen; makes it practicable to connect a tele- yet they are utilized for purposes of wirephone circuit with the earth at both ends less telegraphy, and those of them which without inviting the slightest suggestion are relatively low down in the scale of of such disturbances--a very important frequency can be employed to carry mesfeature of the invention, in Major sages. Squier's own opinion.

All the vibrations being bunched toThe high-frequency telephonic mes- gether and guided by the wire in a single sages and the local battery messages direction, they can be sent to an enormay exist on the line simultaneously mously greater distance. Hence, the without trace of any “cross-talk' likelihood that long-distance telephones or disturbing noises from other external operated on the new principle will be sources. Earth or ground connections able to carry messages across the ocean form a part of the tuned circuit, and no and even, if desired, around the world. noises from the earth are permitted to Such, briefly described, is the novel pass, because all such ground connections idea which seems destined to revolutionare tuned to frequencies far above the ize telegraphy as well as telephony; for human auditory limit.

it is as applicable to the former as to the Very essential is the fact that the con- latter. It ought greatly to cheapen both. densers used are of a capacity so small But Major Squier seems to think that as to be measured in terms of thou- one of the most important advantages of sandths of a microfarad, and they block his discovery lies in the fact that it can all currents of such low frequencies as be utilized and applied with the apthe ordinary telephonic currents, or those paratus already in common employment. which bring disturbing noises from ex- Its application does not demand a single ternal sources.

instrument that cannot be purchased for The whole range of electro-magnetic a moderate price in the open marketvibrations is viewed by Major Squier as for which reason it is at the service not a spectrum extending from the ultra- merely of the telephone and telephone violet, which is a region of high fre- companies, but of any private citizen. It quencies, to the exceedingly slow oscilla- is the property of the people. tions of the infra-red, such as are used on All of the experiments with the multilong-distance submarine cables. One plex telephone up to date have been conmight say that these are terms of light; ducted over a single circuit, which conand so, indeed, they are. But, as the nects the research laboratory of the Siginventor explains, light and electricity nal Corps—at the Bureau of Standards are the same thing. Vibrations within —with the construction laboratory of the certain limits of frequency, as already Signal Corps, on Pennsylvania Avenue, stated, can be heard over a wire. Above close by the War Department, in Wash20.000 a second they become inaudible ington. The distance between the two to the human ear. When they have got points is about five miles. Over this line up to 700,000,000,000,000 to the second, the new system is now in operation.

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HERE IS THE "RUTHLESS EXAMINATION” THAT NEWSPAPERS OF A CERTAIN CLASS

SHRIEK ABOUT.

MAKING THE

THE TOURIST HONEST

By

CHESTER CARTON

C

ONSPICUOUS in the throng for an Arctic winter excursion, and yet

upon the decks of the Kaiser it was a grilling hot day. The seasons Wilhelm II. while she was keep fashionably late hours in New being laboriously warped into York, spring lingering into summer and

her berth at Hoboken one summer lapping over into autumn. day last September were fifteen dignified At the imminent risk of sunstroke the matrons. At least they tried to look dig- fifteen kept their new fur coats closely nified, but realizing that they were con- buttoned throughout the wearisome spicuous, and being still more distress- time that it takes to moor a big steamer. ingly aware of the reason therefor, they Perspiration streamed from their red made rather a poor fist of it. For all faces as they staggered down the gang the fifteen were swathed in obstreper- plank, and distributing themselves among ously new Persian lamb coats which the lettered sections of the torrid dock, would have been admirable garments began the vigil of their baggage. By

was

have on,

the time her trunks were all assembled You will observe that the law distinctly ready for the customs examination the says that only one hundred dollars worth lucky first one was on the point of col- of goods purchased abroad may be adlapse. When asked to acknowledge her mitted duty free. If you will kindly step signature on her declaration, she could to the desk, madame, I think you will be only gasp and nod her head. The in- allowed to amend your declaration." spector to whom the document

No thermometer would have recorded handed glanced at it, then at the new that matron's temperature when she Persian lamb coat.

realized that she had sweltered in vain, “That is a handsome coat you

and that she must pay $130 in duty bemadame," he remarked, seemingly bent fore she could take her prize away. Her on making conversation.

impotent rage was scarcely assuaged by “Yes, I think it is rather fetching," the knowledge that each of the other murmured the melting one, finding her fourteen were making the same discovvoice again, for no woman is ever too ery in other parts of the dock. There far gone to rise to a neatly turned com- are times when misery is too much enpliment.

grossed with its own unhappiness to care “It has the real Parisian cut. You whether it has company or not. must have purchased it abroad.”

Not until weeks afterward did "Oh, yes! You cawn't get such furs nebulous suspicion in the minds of the at home.”

fifteen crystallize into a conviction that “I see you forgot to include it in your he whom they had thought such an declaration."

agreeable young man on the ship com"Why I'm wearing it. Don't you see? ing home was a fiend in human shape, an I'm wearing it."

abandoned wretch with a perverted sense “That makes no difference whatever. of humor, who had played what he was

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TRAGIHL

eve, 1008. VERKOOD & UNDERWOOD, N. Y.

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