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This Proof Is sent to you for discussion only, and on the express understanding that It la not to be used for any other purpose whatsoever.— (SVf .sv. yj ,'f ik- CvHi) (faundiitn ^ocidii o( (fivil (^nginrrrit. KMT\UI.I)SIIKI> IHIIT. To he, raid tn Novf.mlier. TRANSACTIONS. N.D -This Society. Ma lioilj, uiu'i not li.>l(l llai'll rmpciiMilih^ (or tlin f«rt« and opinion Htutntl In Huy of ItH i.ublionlli.nH, Pa|>er 8. THK TKf.KPIIONE. (By F. N. QisBOKNK, M. Can. .Soc. ('. K., P.R.S.O., &c., &c.) Many anil hitter Iluv.' biwn tlip writiiii;» anil ili»ciis»iniis a« tr the Oriyhiiil I n imlnr i\f {\w Ti'lc|iliiini'. The iai'iii'.--t /'r.,,-,/, villi' (.(,|,y nl' llir '■ .lahr.'sliiTiclit." iif l.Slil, in thi' HrilMi Miis.nni. pinvcs tlial I'lillip lliiv "I' Unliii, liaii thiMi cxirti- ni™t«il, with III,, uviiwiil (ilijii-l nr Ininsnilltimi >/,mli l,y ..Icctricity, and that nnisiial .«iinnils hail In'iii wnvi'yi'd hy his a|i|iaratns. MnreiniT. hin nriv'inal Instiunaiit.s imw ri'|irii(liicr f|i,'ich, when the rli'ctinilcs an; mois'.cncd with a drup nt'waliT, nr nil. I'iftMi. , -. rs liitor, 187(i. Prnliwnr Kli.sha (iray, whili' indiavnring to In.nsmll s/ieerh. inventi'd his hiiniiiniii- lilr./ifi/tli , and (fraham Bell, who was In .search nf a linrm.iiic Itlnini/ih (viilchis nrij;iii:il I'nit.'d Stales I'atcnt of If "11). disnivi'i-rd iho siujph' and lieaiilirnl niethnil nf liiiiixniilliiiij .yiiirl,. whirh has sinre Ik'sIhwimI iipnn him taine and for- tnne. Two years later. 1S7rt. I'riil'e.s.Mir Iliiirlies i:raliiitni:sly frave to science and the world, his niiirnpliom- : and liaseil npnnsneh dismvery. vi/., the varying; resistam I' earhnn elirlrniles under inme nr less pressure Thnuias A. Kdisiiniiu lilted and iinprnved teleplmnic transmitters; and iinw the enmliined inventions „r Hell, Kilison, (inwer, lilake and nthurs ennstitnte the inn nial valin' nf thnse Hell Telephone ( 'ompany's aeijiiired patents wLiili have lurn upheld liy the law courts of the I Jiiited States and Enrn|»' with sneh lilierality of scope as jjreatly to astonish the scientists of ,he world. Innnmeralile atten_ipts have consequently been made to transmit speech nilhniil IntYuiijimi upon original patents, ami to such efforts are we, in great measure, indelit<'d for llie reseaielies nf and rusnlt.s ob- tained by electricians of note: fur allhnnoli admirably effective under favnrable environment, the tidephone is stiM susceptible nf material imprnveininl, and alreaily «■.■ have inatliemalieally enneel IlirmnhL- and laws as a guide fnr e.viieriinenters in the pniitieal transmissiun of simnd waves by elect riial impulses. The diverse thenries advanced by prnminent eleetriiians, at a Ittto meetiin; of the Snciety nf Telegiaph Kn-ine,rs and Kleetricians, Lon- don, is my apology fnr nieparing the present paper tnr di.senssion, and I Uiay at nnee state, that the fnllnwi.ig re,|nirements ure tssenlial to the .satisfaiinry transmissiou of speech. Isl, That artiinlatinii shall be clear and natural in tone, lind. That the apparatus shall be lice frnm inductive or extraneous sounds. 3rd. That increased cK-ctrical energy ti.r loiimlistance tranaiuiieion of spit'ch and hmdncss of sound is desirable 4th. That a material reduction in ibe nnniber nf win.snr circuits, at present rei|uiieil fnr a Telepbnnie Kxelnnige, is the essential elemenlfnr ecininmy nf mainii'iiance. .\l the nieeliuL' already lelerreil tn. I'rofessor Sylvanus ThiUHpson Mjitcd : - That all iliaplirains and springs have distinctive tones, thun thiw of low funilainental pitch imjiarl a /.,„.„,,/ sniinil in reprniluced s|K'ech. while bigber keyed niies, yield a nietidlic or Himi/ sound. That the transmission of electric impulses from sound waves are not delK'nilciit upon the varying resistances nf the clcccroilcs under pres- sure ; but are laTasioiu'd by the millions nf minute eleelrical disoharKen between the mnlecnlcs wbieh lly In and frn In^twivn the adjuRtible eleclrndes, from higher to lower potenti.il, a- they approach or recede under the varying tiirces of smind waves ; and that the cft'ectiveiu'ss nf traiismitleis was improved, as their electrodes rise in t<'m|H'rature, cither by applied heal or fmin the passing nf the electric eurrenl«. This stutei It was in pint eudni-ed by Mr. Strocb (formerly assis- tJinl to Sir ('has. Wheatstnnei, whn remarked, that he did tint Wievd in the effeetiMiiess of o/iy,/i',-,/ heat: but that nhen flic current first passes |lnnni;b ti.e eleclrndis. their minnti' points nlf.-i- s,. uiuch resist .1.... 1. . . ; '. . 11,1 I ... that hi tacts bet! produced and they bninnff, sn that the siirfa 'cntne larger ami the n St riimenis conviy speech , lint when Uiyp. Hilencp unmii'M; — thiit wh«n praporl;r adjusted, a ripid bombard- uii'iit ul' uicivoat-ii' iiluins liitwiH'ii tlu' I'kctroiluK occur, vpry i|uickly friiiii the positivo ami imiri' slowly Iriiiu tlir iii');iitiv« imliv And he iiixtuiiui'd the lolinwiii^ I'tiriniix c'.x|K'i'iiii<'iil. iniiliT uiicniHCNipir nbm-rva- tiop. that whuii a tlmp ol' oil whk iilnrcil Ix'tuiiii two platinu pointed electrodes lUid a current pufwd Ihron^h thcui, j. (rrcat dinturhnncc took place between the [larticU^s ol' oi!, wljch 'otated Iwtwyeu the puiat« with wonderful rapidity, one |ioint IxM'ouiinif holler Ihicn the otber, ai> in the eleetrie are lijfhl I'houiiih res'erniii),' thi' (Hilarity did not I'lirur-i'- abli/ piverse their heat. PmfesNitr SylvanUH Thonipson ftiited thai ihi' Miap souml- lii'ard in telephone!!, which arc generally altribiiU'd ln a microphone, all kindsand i|Ualilie.sot'sound ciiulil Is' olilainiil liy nianipiilaliii^' the points, thus clearly proviufi that it is not the tick of the iriilrh which is heard, but the mierophom's uim sminilii, started hy the tick ot the wa'eh ; and that troui such fact it would ap|H'ar that the ineehanical movements due to so\iiid wavi's have thi' effect of ^'ovcrniiiK anil ciail rolling the frec|Uency. auiplitudi', and torin of the vibrations which the iniirophoiu! acts up throu^'h every disturbance of its e(|uilibriuiu. Professor Thompson further stali'd that by usinn a differentially wound inducliou coil in tlu' tran>mitler. not only is a'-ticnlation greatly improved, hut llii' vibratory induction disturbances, from approximate running ma<'hinery. are inoi'uons even to a .senfilive Wake transmitter, and that two small induelion coils, having' their primary wires united in parallel and their secondaries in series, irave a much more satisfactory ri'sult than is olitainaiilc from tlii' ordinary coil in present use. That ;rraiinlatcd harilened coke, as used in the lluniiin^'s trans- mitter, presents more numerous points of contact than two solid elec- trodes, anil hence the L'reutcr vibratory elfect produced in a distant re- ceiver ; but that comparative tests between metallic alloys, demonstrate, that a platimi point, restinsi: upon an electrode of copper, treated either with a mixture of >ileniiiui and sulphur, or with tellnriniu. reproduces speech with a clearness of articulation far superior to ariythiui; obtain- able from bard earboii. althoUL'h such alloy reipiires u irreater initial pressunr, at the clcetroiles. than is reijiiired by carbon. For manv l .••etical reasons. I consider this latter statement of l*ro- fessor Thompson's an im|ii>rtant one. Professor Thompson then exhibited a transmitter, desipied with the object of dis|K'nsinir with tin; patented diaphra::in. .\t the small end of a sjx'akini^ tube, a *'all or valve of metal lesleil t:|H>n three na-tjiUic points and the souml waves snspeiuled. or in part relieved, the weight of the ball ; but I'rofessor Hul-Iics ob.oTved. that if the tube was plu^)i;ed below the valve and the air allowed to escape through side holes, the instrument remained ei|ually effective, thus provim; that the tube Itself U'came a diaphrairm o!' diHiicnt tiirm. ami that umler any circumstances, lor well known ineehanical reasons, the practical limita- tion of three jsiints of support would render the instrunuMit less jiowcr- ful than many others in use The experimental transmitter just deseribed will serve in i^rcal nu'a- sure to explain llie liroad i laini allowed at law in favor of the e of a lew drops may be localized by the application of a delicately constructed telepbonie receiver ; and 1 have little .limlit but that innlcr favorable eircumstanees dislini't si-joals can Iw leiephonieally conveyed throuirli several miles c, I water. Ma;;ncto electric transmitters have, since the introduetion of the microphone, been su|crsedeil by li.eal eircuil balliry power transmitters ; but I am of opinion from pr.ietie il ex|K'rimentf made with the • (ii ibornc & K^ eley " jiatentcd b'lephone. |uiieh;ised by the Hell Telephone (.'o. of Canada, that it is desirable it possible, to dispeiiM> wiib the .ilways uncertain and vai-yin^' action of introduced galvanic battery |H»\ver. Professor Thonipson sni!f;esled a transmitter based u|H>n the principal of a dynanmelectrie Lnaebinc ; but the advauta>!es of such mode of illcreasiu^ thc)Hiwer oi' liie currcnta would Ix; more than (^onnterbalanc- cU by the increased inertia cuusei|Uent U)sjii tin to .ntd tlo iniAeuient of the armature. In concludiuL' bis observations at the mceliuK lo which [ have rofereticc, ProfesBor Thompson staled thai iu his opinion the proi;ress of long distance Iranluiission nfHpeech would depend upon inoreasing the power of the transuiitter, ami redncinutlieseniiitiveneiiii of r^iivars tuindueed sounds I'loni cxlranisuis disturhatiees. To such (general conclusion Mr. W. II. Preece (electrician to the lioniloii Post Office and telegraphs,) look exception, and slated that clearness of articulation and lon^ distance t<'lephony de|H'nded entirely , upon the line wires Iteinir freed from eleetni-statie and elei^tro inagnctu; iuduction, and ',.hat when the environment was favorable, the most urdinury form of instruments would convey s)H;ecli as well over loiif; as over -liorl circuits. That the law. which deWrmines the transmission of currents throu)2h a wire, lo produce H|H'ech, is pnciscly the . ame, in every resis-ct. as the law which determines the How ol currents through subinarii.e cables, and that it is absolutely iniisissiblc, to obtain any Vfriiitcr uumlier of signals, along a given comluctor, by any alteration or improvement in the instruiuents. That the ratio values of conductors were as follows: iron I.Odl*. copiH'r in cables l.lilM), cop|ar exi«)sed 1,.''>00. That the diffiicnce between iron and eop)Hr was due to the self iuduetion of the iron; and between copper in cables and cop|H'r exposed, the difference was entirely due lo the insulation ol 'he former ; the leakage from sns|H'nded wire enabling it to ilisidiarge i- static charge, and still more i|uickly from a sus|H'ieleil i'np|M'r than t'rom an iron wire. That ex|Hrimcnts showed, that wlieii the sja'cil of the currents was .1104 to .OIi:i of a second, the Irausuiission ol siktcI" was bad ; when ,00a to .002, i' was fair ; when .002 to .001, it was good , and if under .001, perfect. And that the average nuuiberof sonortius vibrations in the human voice, was ttbiuit 1,500 j»T second. Kxpcrimeutsniade upon the Irish cables and lines proved the relative vabns of the diffen nt circuits, and that even with a powerful ' III rliiier " lrall^llliller. the rati' of speaking was iieitlur incniiseti nor varied from the result ubtaimd when ordinary transmitters of much 'ess power were used. That Professor I'Memiii!: Jenkins had verified the law of static induc- tion and eonsei|Uenl retardation of signal:', tlirough the Krench Atlantic cable of 2600 miles in length, when he liiuiid it (Kissible lo obtain ':h reversals of current, |H'r second ; and that Isith theory and practice demonstrated that sjKsib was limited in suchclassof cable to adistance of not exceeding !tli lo 100 miles of its length. That ti'le; lionie disturbances are prim^ipally due to secondary cur. reuls induced by priuniry currents in neighboring lim's, and that short circuits are more disturbed by such influences than are long circuits, such disturbances Iwing due, not merely t(. the strength or (lolcntial of neighboring current-. Imt to the rale at which said currents ri.se aiid fall. That although the effects of induction might in some measure lie neutralized by striiiglbening the transmitter and weakening the receiver, it would W almost iinpo.ssiblc to convey intelligible s|H'ecli. wheti very strong currents (sucli for instance as were used in a Wheatstone trans- mitting telegraph) were traversing peighboring lines, the induction effects from said currents laing I'lO.OOO times stronger than telephonic currents. Professor Ilusihes was of opiuion that greater attention should be given to the transmitter induction coils, and that the battery cells and piimary wire of the coils should be in pro|sirtion to the internal re- sistance of the transmitter ; and he agreed with Protessor Thompson, that more |siwerfnl transmitters and less sensitive receivers iudieattfd the path of progress in telephony. Professor Bidwell held, that the constituentelements of a transmitter s.hould be an arrangement in multiple-are of heavy carbon pencils, with light [Hants of contact, that the resistance of such a microphone should be proportionately as small as the rest of the circuit, and that the cur- rent should l)e as strong as the number of contacts and amount of pres- sure would warrant. With due regard to tlu> foregoing views and experiments of eminent ehetrielans. I venture to express my opinion. That clearness of articulation ami natural tones ate best obtainable from magneto cK'Ctrie transmitters, which are free from the disturbing anil varying action of local .ualvanic cells. That loudness, and progress in long-distance telephony, will depend in L'reat measure upon iticreased power in the transmitter and decreased s