heroes of the telegraph-第30节
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。 The results were described in a paper 'On the Radiation of Electricity；' which； in 1859； he posted to Professor Poggendorff； for insertion in the well…known periodical； the ANNALEN DER PHYSIK。 The memoir was declined； to the great disappointment of the sensitive young teacher。
Reis had studied the organs of hearing； and the idea of an apparatus for transmitting sound by means of electricity had been floating in his mind for years。 Incited by his lessons on physics； in the year 1860 he attacked the problem； and was rewarded with success。 In 1862 he again tried Poggendorff； with an account of his 'Telephon；' as he called it；＇The word 'telephone' occurs in Timbs' REPOSITORY OF SCIENCE AND ART for 1845； in connection With a signal trumpet operated by compressed air。＇ but his second offering was rejected like the first。 The learned professor； it seems； regarded the transmission of speech by electricity as a chimera； but Reis； in the bitterness of wounded feeling； attributed the failure to his being 'only a poor schoolmaster。'
Since the invention of the telephone； attention has been called to the fact that； in 1854； M。 Charles Bourseul； a French telegraphist； ＇Happily still alive （1891）。＇ had conceived a plan for conveying sounds and even speech by electricity。 'Suppose；' he explained； 'that a man speaks near a movable disc sufficiently flexible to lose none of the vibrations of the voice； that this disc alternately makes and breaks the currents from a battery： you may have at a distance another disc which will simultaneously execute the same vibrations。。。。 It is certain that； in a more or less distant future； speech will be transmitted by electricity。 I have made experiments in this direction； they are delicate and demand time and patience； but the approximations obtained promise a favourable result。'＇See Du Moncel's EXPOSE DES APPLICATIONS； etc。＇
Bourseul deserves the credit of being perhaps the first to devise an electric telephone and try to make it； but to Reis belongs the honour of first realising the idea。 A writer may plot a story； or a painter invent a theme for a picture； but unless he execute the work； of what benefit is it to the world？ True； a suggestion in mechanics may stimulate another to apply it in practice； and in that case the suggester is entitled to some share of the credit； as well as the distinction of being the first to think of the matter。 But it is best when the original deviser also carries out the work； and if another should independently hit upon the same idea and bring it into practice； we are bound to honour him in full； though we may also recognise the merit of his predecessor。
Bourseul's idea seems to have attracted little notice at the time； and was soon forgotten。 Even the Count du Moncel； who was ever ready to welcome a promising invention； evidently regarded it as a fantastic notion。 It is very doubtful if Reis had ever heard of it。 He was led to conceive a similar apparatus by a study of the mechanism of the human ear； which he knew to contain a membrane； or 'drum；' vibrating under the waves of sound； and communicating its vibrations through the hammer…bone behind it to the auditory nerve。 It therefore occurred to him； that if he made a diaphragm in imitation of the drum； and caused it by vibrating to make and break the circuit of an electric current； he would be able through the magnetic power of the interrupted current to reproduce the original sounds at a distance。
In 1837…8 Professor Page； of Massachusetts； had discovered that' a needle or thin bar of iron； placed in the hollow of a coil or bobbin of insulated wire； would emit an audible 'tick' at each interruption of a current； flowing in the coil； and that if these separate ticks followed each other fast enough； by a rapid interruption of the current； they would run together into a continuous hum； to which he gave the name of 'galvanic music。' The pitch of this note would correspond to the rate of interruption of the current。 From these and other discoveries which had been made by Noad； Wertheim； Marrian； and others； Reis knew that if the current which had been interrupted by his vibrating diaphragm were conveyed to a distance by a metallic circuit； and there passed through a coil like that of Page； the iron needle would emit a note like that which had caused the oscillation of the transmitting diaphragm。 Acting on this knowledge； he constructed a rude telephone。
Dr。 Messel informs us that his first transmitter consisted of the bung of a beer barrel hollowed out in imitation of the external ear。 The cup or mouth…piece thus formed was closed by the skin of a German sausage to serve as a drum or diaphragm。 To the back of this he fixed； with a drop of sealing…wax； a little strip of platinum； representing the hammer… bone； which made and broke the metallic circuit of the current as the membrane oscillated under the sounds which impinged against it。 The current thus interrupted was conveyed by wires to the receiver； which consisted of a knitting…needle loosely surrounded by a coil of wire fastened to the breast of a violin as a sounding…board。 When a musical note was struck near the bung； the drum vibrated in harmony with the pitch of the note； the platinum lever interrupted the metallic circuit of the current； which； after traversing the conducting wire； passed through the coil of the receiver； and made the needle hum the original tone。 This primitive arrangement； we are told； astonished all who heard it。 ＇It is now in the museum of the Reichs Post…Amt； Berlin。＇
Another of his early transmitters was a rough model of the human ear； carved in oak； and provided with a drum which actuated a bent and pivoted lever of platinum； making it open and close a springy contact of platinum foil in the metallic circuit of the current。 He devised some ten or twelve different forms； each an improvement on its predecessors； which transmitted music fairly well； and even a word or two of speech with more or less perfection。 But the apparatus failed as a practical means of talking to a distance。
The discovery of the microphone by Professor Hughes has enabled us to understand the reason of this failure。 The transmitter of Reis was based on the plan of interrupting the current； and the spring was intended to close the contact after it had been opened by the shock of a vibration。 So long as the sound was a musical tone it proved efficient； for a musical tone is a regular succession of vibrations。 But the vibrations of speech are irregular and complicated； and in order to transmit them the current has to be varied in strength without being altogether broken。 The waves excited in the air by the voice should merely produce corresponding waves in the current。 In short； the current ought to UNDULATE in sympathy with the oscillations of the air。 It appears from the report of Herr Von Legat； inspector of the Royal Prussian Telegraphs； on the Reis telephone； published in 1862； that the inventor was quite aware of this principle； but his instrument was not well adapted to apply it。 No doubt the platinum contacts he employed in the transmitter behaved to some extent as a crude metal microphone； and hence a few words； especially familiar or expected ones； could be transmitted and distinguished at the other end of the line。 But Reis does not seem to have realised the importance of not entirely breaking the circuit of the current； at all events； his metal spring is not in practice an effective provision against this； for it allows the metal contacts to jolt too far apart； and thus interrupt the current。 Had he lived to modify the spring and the form or material of his contacts so as to keep the current continuousas he might have done； for example； by using carbon for platinumhe would have forestalled alike Bell； Edison； and Hughes in the production of a good speaking telephone。 Reis in fact was trembling on the verge of a great discovery； which was； however； reserved for others。
His experiments were made in a little workshop behind his home at Friedrichsdorff； and wires were run from it to an upper chamber。 Another line was erected between the physical cabinet at Garnier's Institute across the playground to one of the class…rooms； and there was a tradition in the school that the boys were afraid of creating an uproar in the room for fear Herr Reis should hear them with his 'telephon。'
The new invention was published to the world in a lecture before the Physical Society of Frankfort on October 26； 1861； and a description； written by himself for the JAHRESBERICHT； a month or two later。 It excited a good deal of scientific notice in Germany； models of it were sent abroad； to London； Dublin； Tiflis； and other places。 It became a subject for popular lectures； and an article for scientific cabinets。 Reis obtained a brief renown； but the reaction soon set in。 The Physical Society of Frankfort turned its back on the apparatus which had given it lustre。 Reis resigned his membership in 1867； but the Free German Institute of Frankfort； which elected him an honorary member； also slighted the instrument as a mere 'philosophical toy。' At first it was a dream； and now it is a plaything。 Have we not had enough of that superior wi
