25 



the earlli of llic tcleplione, aml in every case by Iheinduciiig 

 ariioii ol' llic coils iijioii oiic aiiollicr. The irileiisily oï llie 

 lelephoue-curreiit is a vt^ry siiiall oiic, aiid depeiids on Ihe 

 varialions ol" Ihe niaijnelic liold : on Ihe conlrary ils leusioji 

 is hiiïli and llierelore ils (hiralion shorl. 



Witli regard lo onr exaniinalion httwever il can only 

 l»e uecessarv lo pul Ihe (|neslion , whal happens in 

 Ihe lelephone 7'-,. as sooii as il reeeives ils poiiion oI" llie 

 rnrrenl coniini; Iroui '/.,. Th(^ leply lo Ihis ([neslion ean 

 nol he (hmhUiil al ali. TUv. arriving ciirrenl |>asses llic 

 coil wonnd roiind Ihe lelephone-hohbins, and llows lo earlh. 

 Decreased in Ihe hejiinninii hy Ihe exlra-currenl , flowuig in 

 llie reverse direclion. ils ellerl is increased l»y Ihe exira-enrrenl 

 in llie sanie direelion. 



How d«»es Ihis sccoiid exlra-cnirenl Wow' 



Il seenis Ihal Ihis ciirrenl wili divide in J5, as il is heginning 

 in 75. and Ihal one portion of Ihe currenl will circiilale in 

 Ihe vvay A:^A<iHHl\, and ils olher porlion in Ihe way 

 .MiA/^7V 



TJie leleplione-(iui(Mil coming IVoin 7'^ and Howing lowards 

 7'i will Ihus hc overpowered liv Ihe second exlra-currenl in 

 Ihe way l'AAiA:,, since il llows in a direclion conlrary lo 

 Ihe cnrrenl ot' Ihe lelephone. 



This second exli"i-cnrrenl appears lo hc sliong enough lo 

 alVecl the lelephone in T\. 



Tluis Ihe exlra-cnrienl ilsell" serves lo Iranslale Ihe currenl 

 cansed hv Ihe words spoken in T-i, and Ihere is no need lo 

 niake nse ol" si^parale insliinnenls lor Ihal pnrpose , as il is 

 Ihe cas(ï in lelegraphy. 



Al prcsenl I dnn'l pnssess a siillicienl niindicr of lelephoiK^s, 

 lo cxauiine whiMhcr il is possihie lo lianslalc Ihe cnri'enl 

 more thaii once . nlini nsiini inri's oj r.rlnionhiiiirii IcikjI/i i' ". 

 Ihal is. il" llic. samr rcsiill willlic olilainctl wlicn Iherc ar(^ .vcrc/v// 



1) l-lxfK'iiciicc li;is l.iiitïlil. lli.'il llli^ iii.iy nciiic wlicii wiics ui' nrdiiiiiry 

 Iciiiilli ;ii'(' iiscd. 



