SOMETHING ABOUT THE TELEPHONE.

Thames Star, Volume VIII, Issue 2897, 29 May 1878, Page 2

SOMETHING ABOUT THE TELEPHONE.

' B\N.

'■ ■ The Telephone is causing a great deal of coruusion as we'l as intenv.t. Though the instrument itself is a vory simple affair, it has puzzled a large number of persons, add to tbis day rotne o!'our professedly scientific men d j noc at «li undersUnd thj method* by whichwords are repeated, at the distant end of a wiroi Some hare expressed an idea that the waves of sound rctually (ravel through the wire, and some very ingenious arguments have been based, upon ibis belief. For example, a writer in a recent number of the AtieLseum undertakes lolLiow that Professor 1011, of Boston, ha 3 received a great deal ,too much praise, and that he is not the inventor at all. This honor, it is said, fairly, belongs to Professor Wheatstone, who discovered ihat sound could be coave^ed through wood and wire for a iong distance 'jours before b invent d his electric telegraph. The writer then proceeds t j give various examples, such as the ticking of a clock being conveyed through a long wire, and a violoncello being mado to play by being connected with another instrument by a wooden rod. Therefore, says the writer, Professor Bell is not entitled to claim any honor for the invention of the telephone, because Sounds were conveyed through various media long before Professor Bell was heard of. This may be regarded as a very curious example of what the Yankees call barking up the wrong tree. No doubt Professor Wheat-' stone did cause sounds to be conveyed as stated, arid sounds were conveyed through gas pipes in the streets of Paris very many years ago. It was found that a flute played at one end or a line of pipes could be heard a long distance off, and almost everybody knew that music could be carried by means of wooden rods from one room to another. All this* is common enough. .We must concede that if Professor Bell bay merely conveyed sound a longer distance than other folks, hj has only extended a principle which he aid not discover. A^ain, some; of the experienced telegraphists in this colony think that the presence of electricity helps the sound along—that is, gives it a sort of kick behind, and thus makes it " move on." -At other times we find seme curious illustrations as to how the thing is not understood by the citing of the ordinary trich witli two tin cans covered with parchment and united by a piece of thread as an example of a small telephone which anyone can make for himself. Now, all these arguments and illustrations are based, I conceive, on a very great mistake—in fact on a total misapprehension of the principle, the essential feature, of the telephone. The telephone is an electric instrument or it is nothing. It acts by the aid of an electromagnet, aad could not act without it, so so that to cite what baa been done 'n the way of cfweying actual sounds : * notb- j

ing to the purpose. Experiments made in England go to show that the stren^lh of the vibrations of the diaphragm are" greatly increased by the uee of what may be called outside electric power, and. t Nat a wire charged already with electricity conveyed the vibrations much moie readily than one noi already charged. This points to a direction in which it may be possible to improve the claraeier of the instrument, and cause sounds to be repeated, not only so that they may be heard by one listener, but bo that they may be heird by coveral. The manner in which the telephone acts app^s to be cle- rW as follows. Ey the movements of .the diaphragm, which vibrates to the sound of the voice, •or to an instrument, electro •magnetism is set up in the magnet in the coil within the case. This electricity is conveyed by wires to the main line, wherever it may be, a proper circuit being, of course, formed by a wire into the ground, aid tbe effect is to repeat at one end what t^kes place at the olbe/. . Thus, the vibrations of the diaphragm onen or shut the cir cuit, just as uots and dasbes are made, the result being that th.3 sounds of the voice are not heard, but pre reproduced.' The ac-, tual sounds do not travel beyond the dij^ phrpgra where they are spoken, but currents of electrcily travel corresponding to the vibrations. Evidently, if we can repr< tuce the vibrations we can reproduce the sounds, because the sounds are only vibrations, and the pecu'iar merit of Pro* fessor Bell's discovery is t'lis, that he for id out how to reproduce the vibrations at a very long distance. It was known • before his time that sounds could be re-. producd by means of a silk thread end a couple of srrall drumhe:ds, so to speak, but that was a mechanical reproduc* tion, capable of only being carried on for a short distance. Professor Wke-L<'3i.one's experiments, as those in Pa-is and ekewhere, were for the conveyance of sounds or vibrat'ons, and the limit to that p-ocess is soon reached. Profee: o.> TelVs discovery is tbe me as of making elec-.'ic ca:_ents reproduce the vibra<ions of a diaphragm, and it is impossible to aay wLat liimip can be placed on this metbod. At present ihe carvents are weak, and tie vibrations necessarily so also ; bat, a" Ir< ye ca:d it :s possible-1 th t the cc -enis may be n»." 'c sponger and t J >e Jnten-'ty of the vib" lions incre :ied. From what I have said it will be s, en that aU,rej»,.-*eDce~ to the actual conveyance of sound are ou S'de the question, ard cannot affect tbe work which PVofessor Bell has doae. It has been objected that if the actual souuds were not conveyed we should not be able to distinguish the (ones of voices, nor could we tell what particular instrarrest was baing played. Those who make tbe~e objections, and they are mere numerous than might be suppoVd, are ignorent of what is the distinction between o^e voice and another, and ona irsi.rument and another.. Musicians and many persors besides know that every ivi umeit brs not only notes but harmoi?:es of its own, and that when a note, is p ay i we not only hear tte vote itself, but re .'lain brLjeorne- as well. These, though not generally noticed, c "i be d:sthgr.shed by an acute »nd (•? iced ear, and tbeir ex;sten r3 bas b n demon* strat.d <o tbe eye by Professor Tynda'l. He plac'd sops, of''wood oa various i .vt of a vibrating, sfrins,' and be thus £.how d tbat tin stiing not; o >!y vibia. .dja.erally, bat broke up into a number "of "sections of waves,-of various sizes, according to the rib'.ation of the 8 ..ing. Wle:ey*r a harmonic occurred the stops remained unmoved, but they werj thrown off tte other portions of the suing, thus showing to the eye the positions of the different" 1: armonics ii diffe-ent spiings. Now, this is true of all vibial;og bodies, no ra-lLer whether they be , strings or plates, a piecs of glass ov a piece of iron. We can see, therefore, f" at one person speaks against the diaphragm of a telephone he produces different vibrations from another, and these, we come to rccoprise as the distinction between the voices.. Instruments differ in a like manner, and thus, without the -dual sound being coareyed,- we are able to distinguish voices, instruments, and even modulations o. delicate rounds. This is, beyond question, the principb of the telephone, and it is surjv'sing that it should have been so much misundei'steod, especially by a writer-* such as the one in the Athenaeum— who claims to have a knowledge of scientific principles. If we wish to test the matter furth.r, we have only to attend to the question of time. A "cooey" may be sent from Melbourne to Ballarat and be repeated back in a second, or less; whereas sound would take a long time to travel that distance, even if it could be heard by any possible arrangement. We may, therefore, safely conclude tat the sound is. not convoyed, but that instantaneous electric currents repeat the vibrations of one end at the other, and so give the sounds as they were uttered. Let us hope that we shall have no more disputes about Professor Bell's merits, bated on tJ- c assumption that he claims to transmit sounds,- when he distinctly asserts that he dees not claim to do anything of the Fud.—Australian.