My Inventions Part Four - The Discovery Of The Tesla Coil And Transformer

Date: 
Thursday, May 1, 1919
Volume: 
22
Pages: 
16-89
Author: 
Subject: 

May, l‘) I9 ELECTRICAL EXPERIMENTER I7 road station in Strasshurg, Alsace. The wiring was det`cct\\'e and on the occasion of the opening ceremonies a large part of a wall was hlown out thru a short-circuit right in the presence oi old Emperor \\'illiam I. The 'lit-rman (iovernment refused to take the plant and the French (`ompany nas facing a serious loss. On account of my knottlcdge oi the German latigtutge and past experience, I was untrusted with thc ditiicult task of straightening out matters attd early in 1833 I went to Strasshurg on that mission. ri \\ )`\ '\ /\ , \ ., ,, VH. ,, ,xy __ _ W, `. 1 ` \ -t 1 ._ t , The Fink tnaueuan Mawr Is l I’ I ‘J ll ‘f ‘ Built. = Some of the incidents in f . -. 5 t that city have left an indel- ible record on my memory. By a curious coincidence, a number of men who suhse- quently achieved fame, lived there about that time. In later life I used to say, "There were bacteria of greatness in that :dd town. Others caught the disease but I escaped!" The prac- tical work, correspondence, and conferences with oth- cials kept ine preoccupied day and night, hut as soon as I was ahle to manage I undertook the construction of a simple motor in a me- chanical shop opposite the railroad station, having brought with ine from Paris some material for that purpose. The consumma- tion of the experiment \vas, ltowever, delayed until the summer of that year \vhen I finally had the satisfaction of _racing rotation cjfrrlrd by ullrrualiug cxirrrlilr of ) 9.1 /, -it conclusion that hc knew no worthier person than myself to consume that precious limeraue. This, I may say, is one of the unforgettable incidents to which l have referred. My friend urged me to return to I’aris as soon as possilile and seel: support there. This l was anxious to do hut my work and negotiations were protracted owing to all sorts of petty obstacles I encouiuered so that at times the situation seemed hopeless. _ _ German “Em¢ien¢y". ,. _Inst to give an idea of German thoroness and "ei- . fidency," I may mention here a rather funny experi- ence. An incandescent lamp _ 1 of 16 c.p. was to he placed in a hallway and upon sc- lecting the proper location I ordered the iuozilcur to run s the wires. After working for a \vhile he concluded that the engineer had to be consulted and this was done. The latter tuavhr suvcral oli- jeclious httt ultimately agreed that tltc lamp shotild he placed two inches from the spot I had assigned, whereupon the work pro- ceeded. Then the engineer became worried and told me that Inspector Avcrdeck should he notified. That im- portant person called, inves- tigated, debated, and decided that the lamp should be shifted back two inches, which was the place I had marked. - It was not long, however, licfore Avcrderlc got cold feet himself and advised me that he had in- formed Obrr-/iirpvrttir Hi- eronimus of the matter and dif7r'n'1|t pliaxif, and willmul ,rlidiug fmilurl.v or commit- lalor, as I had conceived a year before. It \vas ati ex- quisite pleasure lint not to compare with the delirium of joy following the first revelation. "R .w Q T `. 1 Q , A . th i\ .I ~:\\ 1 ' ii-l . 5/ ‘wt l 3 ; . _ ti ' ‘I ll( ' * 1' ,l fl ~ I = if i\' - \ at _ | .tif » . _tt :ii . , ,- , it f x 2 ¢» li, I/V ,1 Z i, '_ 1% ml lt 'P W -t ` `t Y \ .1 ' :i, ."|\ . ,,\ 'I ?=' ~' . V Q Fig. 2-This illustrates Tests With Spark Discharges From a Ball of Fnrty Centlmeters Radius ln TesIa's Wireless Plant Erected at Colorado Springs in 1899. The Ball ls Connected to the Free End Of a Grounded Resonant Circuit Seventeen Meters In Diameter. The Dlsruptlve Potential of .1 Ball, it, According to Testa. In vous /\ppf°><\f~\2¢eIly v .1 75.400 r tr aeinu In Cunklmstarl), Tha! ll. lu Thll Chan 75,400 X 40 3.015.000 VOIKS. The Glnanilc 'ruin can Which Pi-ottawa 'runs ann- of Thor yva- cauatns at Furnlihlh I Current of 1,100 Artlllural In tha Hlult Teltislull bt;c0ntI.t|'y. Thu Primary gun Han a Diameter of 51 Feet! This Tesla con Produced Dls- charge: Whlch Were the Nearest Approach tn Lightning Ever Made by Man. Among my ne\v friends was the for- mer Mayor of the city, l\lr. Bauzin, \vl\om I had already in a measure ac- he f o was I should await his de- It was several days the Obvr-/its/it-rlur ahle to free himself of that cision. re other pri-ssixtg duties lml at last IIE proverbial trials mul lriliululions lrlwtt/it to ut/ery in|'r'ulor were not apurwl l'\'Sl¢1, the world'a greulexl inuenlnr of all limes. in I/tis urlulu iw sm: limi, urriuctl ul young manhood, struggling along in a cold wurltl. .fllrcutly /tts /tune has spread /ar mul wirle and his genius is recognized. But converting genius and fume( into llollurs und rents is quite a dijerelll mutter, mul llm irorlnl is /ull of tnmpprecuillva mul u|m'rupu- lous men. Tesla, the itll-ulisl, cured little /or money mul thus was promptly lulsmi advantage 0/_ Bu! lel Tesla himself tell you in his mrn iuimilulrle style. ll is a wonder- quainted with this and otlter inve utions of mine and whose sup- port I endeavored to enlist. He was sin- cerely devoted to me and put my projt-rt heforc several wealthy persons hut, to my mortihcation, found no response. I'Ie wanted to help me in every possilile way ful story. In this montl\'s insmllme as 'well as sensational disco: sensnlizm ns this one which The Tesla coil Inu so many it catalog to list them ull. F ta lliu "violet" my muz'l|in|~ nt Tesla also It-[lx us /ww he made one of his must im/mrtnnt u-ries -the Teslu Coil. Flew iriuelitiulis have caused xuult a cullninzilvfl in llie unly :nun-uuule lightning ever prnllucerl. uses mul ltus been ltuill in so many stylus /lun iz uumlil mlm rum the sprfrluculur liigli /ruliuuriry stunts on the stage (lawn in »-auf 1..».».~; .ill .iff 'lu-tl.. .-ant in .au /orm or anal/.<~r, _ ' ` 1* ponilrlv tmltw. ll il/mul on on-ill/i» l|"irvli'u tuitlwul lliv 'l`mlu mul wnulil nur If liun Iruns/nrmer, spark gap would lie crippled. llul it is for imluslrirtl future. The production of quantities-all are cliiltlren turd, In I5/tl. uml 4-vi/iilvmrr wliiv/i is u 'l'|»»lu (foil tliw .wmling smnon purposes wlmrt: ilu: 'Tesla Coil will shine Iariglilusz in :lm ():or|¢', /lui uxlrtufliun ol Nitrogen from :lie air in huge 0/ ’l`uslu’x fertile brain. llis will is the /my lu 1Iu»m ull. I!I)lT()lt. l\vi| which was not financial hut none the less ap|n'et"; when the Germans invaded the country, l\lr. Ilan/in had lturu-il a and good sized allotment of St. Iisti-plw of ll~§tll and he <~:mu- to the he arrived and a two- hour rlcliate followed, when he decided to move thc latup two inches farther. My hopes that this was the final act were shat- tered when the Uber- [u_r/rrrlor returned and said to nie: "Re- givr-iiv|g.r1'nllt Funke is so particular that I would not dare to give an order for placing this lamp without his I-tpiu-at tippt-.»v;\|." Avcorilinely arrange- ments for a visit from that great man \vere made. \Ve s t a r t Q d cleaning tip and pol- ishing early in the and the approach of the hrst of july, l9l9, happens to remiml me |uornin=;, »l§vvrvl»orly lirushecl up, I put on my gloves and when of a fornt of "assistance" l |'erri\'t~

May, l9l9 morning without a da 's exception. Edison said to me: “I have had many hard-work- ing assistants but you take the cake." Dur- in%_ this period I designed twenty-four di erent types of standard machines with short cores and of uniform pattern which replaced the old ones. The Manager had promised me fifty thousand dollars on the completion of this task but it turned out to be a practical joke. This gave me a painful shock and I resigned my position. Immediately thereafter some people ap- proached me with the proposal of forming an arc light company under my name, to which I agreed. Here finally was an op- portunity to develop the motor, but when I broached the subject to my new associates they said: "No, we want the arc lamp. We don't care for this alternating current of yours." In 1886 m system of arc light- ing was perfected and' adopted for factory and municipal lighting, and I was free, hut with no other ossession than a beautifully engraved certificate of stock of hylzothetical value. Then followed a period o struggle in the new medium for which I was not fitted, but the reward came in the end and in April, 1887, the Tesla Electric Company was organized, providing a laboratory and facilities. The motors I built there were exactly as I had imagined them. I made no attempt to improve the design, but merely reproduced the pictures as they appeared to my vilion and tie operation was always as l expected. In the early part of 1888 an arrangement was made with the Westinghouse Company for the manufacture of the motors on a large scale. But great difficulties had still to be overcome. My system was based on the use of low frequency currents and the Westinghouse experts had adopted 133 cycles \vith the object of securing advan- tages in the transformation. They did not want to depart from their standard forms of apparatus and my efforts had to be con- centrated upon adapting the motor to these conditions. Another necessity was to pro- duce a motor capable of running etliciently at this freguency on two wires which was not easy o accomplishment. At the close of 1889, however, my services in Pktsburg being no longer essential, I retumed to New York and resumed experi- mental work in a laboratory on Grand Street, where I began immediately the de- sign of high frequency machines. The prob- lems of construction tn this unexplored field were novel and quite peculiar and I en- countered many ditticulties. I rejected the inductor type, fearing that it might not yield perfect sine waves which were so im- portant to resonant action. Had it not been for this I could have saved myself a great deal of labor. Another tlisctnlragiltg fea- ture of the high frequency alternator seemed to be the inconstancy of speed \vhich threat- ened to impose serious limitations to its use. I had already noted in my demonstra- tions before the American Institution of Electrical Engineers that several times the tune was lost, necessitating readjustrnent, and did not yet foresee, what I discovered long afterwards, a means of operating a machine of this kind at a speed constant to such a degree as not to vary more than a small fraction of one revolution between the extremes of load. The Invention of the Tesla Coil From many other considerations it ap- peared desirable to invent a simpler device for the production of electric oscillations. ln |850 l.or

ELECTRICAL EXPERIMENTER May, |919 My Inventions (Continued from page 17) lamp there. It was the exact spot which I had originally chosen. So it went day after day \vi|l\ variations, Init I was rlctcrmincd to achicvc at what- ever cost antl in the end my el`forts were rewarded. By the spring of 1884 all the differences were adjusted, the plant formal- ly accepted, and I returned to Paris with pleasing anticipations. One of the admin- istrators had promised me a liberal compen- sation in case I succeeded, as well as a fair consideration of the improvements I had made in their dynamos and I hoped to real- ize a substantial sum. There were three administrators whom I shall designate as A, B and C for convenience. When I called on A hr told me that B had the say. This gentleman thought that only C could decide and thc latter was quite sure that A alone had the power to act. After several laps of this circttliar ~uitia.m~r, it dawned upon me that my reward was a castle i|\ Spain. The ntlrr fnilurt- uf my :\|\c|n1||~i tn rnisc cnpilnl fnr devclnpnu~|\t was another disappoint- ment and when Mr. Batchellor prest me to go to America with a view of redesigning tl\e Edison machines, I determined to try my fortunes in the Land of Golden Prom- ise. But the chance was nearly mist. I liquefied my modest assets, secured accom- modations and found myself at the railroad station as the train was pulling out. At that moment I discovered that my money and tickets were gone. What to do was the question. Ilcrculcs had plenty of time to deliberate but I had to decide while run- fning alongside the train with opposite feel- ings surging in my brain like condenser oscillations. Resolve. helped hy dexterity, won out in the nick of titne and upon pass- ing thru the usual experiences. as trivial as unpleasant, I managed to embark for New York with the remnants of my belongings. some poems and articles I had written, and a package of calculations relating to solu- tions of an nnsolvable integral and to my flying machine. During the voyage I sat most of the time at the stern of the ship watching for an opportunity to save SOIIIC- body from a watery grave, without the slightest thought of danger. Later when I had absorbed some of the practical Ameri- can sense I shivered at the recollection and marvelled at tny former fully. Tesla in America I wish that I could put in words my First impressionsof this country In the Arabian Tales I read htm- genii transported people into a land of dreams to live thru delightful adventures. My case was just the reverse. The genii had carried tne from a world of dreams into one of realities. ¥Vhat I had left was beautiful, artistic and fascinating in every way; what I saw here was ma- chined, rough and unattractive. A b\trly policeman was twirling his stick \vhicl\ looked to me as big as a log. I approached him politely with the request to direct me. “Six blocks down, then to the left," he said, with murder in his eyes. "Is this America?" I asked myself in painful surprise. “It is a century behind Europe in civilization.” When I went abroad in 1889-five years having elapsed since my arrival here-I be- came convinced that il was more than our lntndrrd year: AHE.-ID of Europe a|\d nothing has happened to this day to change my opinion. Tesla Meets Edison The meeting \vith Edison was a memor- able event in my life. I was amazed at this wonderful man who, without earl advan- tages and scientific training. harly accom- plished so |\n\ch. I had studied a dozen languages, delved in literature and art. and had spent my best years in libraries reading all sorts of stnFf that fell into my hands. from Newton`s "P1‘inti[tin" to the novels of Patil de Kock. and felt that most of rny life had been squandered. But it did not take long before I recognized that it was the best thing I could have done. Within a few weeks I had won Edison's confidence and it came about in this way. The S. S. Oregon, the fastest passenger steamer at that time, had both of its lighting machines disabled and its sailing was de- layed. As the superstructure had been built after their installation it was impossible to remove.them from the hold. The predica- ment was a serious one and Edison was much annoyed. In the evening I took the necessary instruments with me and went aboard the vessel where I stayed for the night. The dynamos were in bad condition, having several short-circuits and breaks, but with the assistance of the crew I succeeded in putting them in good shape. At five o'clock in the moming, when passing along Fifth Avenue on my way to the shop, I met Edison witl\ Batchellnr and a few others ns they were returning hnme to retire. "Here is our Parisian running around at night," he said. When I told him that I was coming from the Oregon and had re- paired both machines, he looked at me in silence and walked away without another word. But when he had gone some dis- tance I heard him remark: "Batchellor, this is a d-n good man," and from that time on I had full freedom in directing the work. For _nearly a year my regular hours were from 10.30 A. M. until 5 o’clock the next

May, l9l9 ELECTRICAL EXPERIMENTER My Inventions (Cnntinurrl /rum /vuyv (15) ('l\|{lllCQl'l of u defect involved ln the trnn§~ like that governing the convcrsimt of mc- formatiun by the new method, namely. the chamcal energy. We may drop a weight loss an the spark _gap. Subsequent mvesti- from a certain height vertically do\vn or l »~' l A/ferna//ng @ 0 0//'ed 11 12 11 1 1 l I I I illll illli lllll lilil lilll lilvl E E I " it 1 >< bl Q \ | i : , X ' és L; - 'tg 1 i 43' ~o» 0900 ; l s f `| iii-Th Jimi =‘°= . , ' _ < ire; 153; i_|-at. Liimyy I ' __ Ilechanico/ Ano/og of lés/0 Osc///0//m Ziwnsbrmerfamy __ Thll rlrlltlllhlllly Imlrovlallll Ill llhllltll Ill Ollllflll ly Tllll lllr lhl llril llml In hll Ilelltrl hefnrl thl Amlrlcln llllllllll || Elldlllll EI|||ulIrl MA! 20, llll. I! hll llldl lllllhll In llnlllil l||\lmAtIu||y llrllned nr ulltllmulti llllllllllhl at lily dllllld lrlltllley llll. lhli ll llllllly Imlllrllnl, ll llrhelly lnmlllnl nlrlod. |\ hu blln Inxlru- hlltll Il llly lnll lchllvllllllltl Ill Ill Ill! hll bewlll lllllilnll. The lllllllrlyllll nrlntlltlh In he hrlllly lllhd lx llllllll A llltfll ll llltlrlllq ll lldl \O ll\|’|l I llllllenllr Ind Illhll the dlllrlltul 0| Dutlntls at th! lurmlnlln nl ihl Illllr hll rlllihltl I lrldl lrlnlllld Vlllll. ll llr-Ill ll lrldlld. |lrmI\t|||| the lcetlmulllld l||lr|y to bl dlwhlrwd lhrltl h l ¢|l¢l|l\ ulllr rlllllltl lioldllilll. lhll rilulllll |lI A Illll llrln ll lluhmnoul Illlrulul. Thu: ul Ill lr Ilnli Illld 0| ullvlrill (ll lly llllrll Vlltlll lfltrllllirl llrllllll ll l liulltl olruttlt llldtlcl vlly Illlkld with tltl flril lld lull! \l \h| llllll. Thl IIN! llzgvll Il I Ill lram ll|l'| lnhln bien the Frlnklln Inntltuls and Nlllonll Elutrln \.||ht Auntnllun In Ilia ul an non olnbsnts arrangements nt elreulti, nw nn- umlllu luv the wu- unlon sl untrue( llrnt nr nltnrnulu mmm! Inu Mun lruuansy oulllntlanl by mln ‘warn mlhnu. In tha lllhlltllll llllrl tll lllullrllld. ll lllllll ll llll 1| nllvq ln llu 0| \hl ullutllull lnllll llll la oleuly Al nrlcll- elhll. Thl r|uIlr¢lll||l'| llll a|llr|||||A.| ltlllei hlfedlvlli, rllrullll ln lIhf|\lll||| and I llreut enrrlnt nnlrltur, Yhl tdltlf hill lhl llll ll ihl lllllrll IMI . hl ml nilr l|\h I\| lllltlellly rn\r\||\ld llltuu rwntlnll \hl elllllllr. Thl |l|||‘\|l 0| the !llll| llrh llfllllelll hi lhl lll|~\||¢\|¢t|0|| Ol the lllatrlo ulrcult and lhl wllll nnrh lrlllll the tqlllllr lhrwah \|h|l|\ (Ill lltlll ul Ulellb. Dlffirm lhl lunntlln ll the llr-Ulf. Thu oplratlsll nl thll nnntul Ill nv be run ly undnntool. tulnuo mt that ttn water In nnlma tn ana cyl naar tram thu auntrllunl Illlll. till Nrrlllllldllt Ill Xhl ulllll of O bllllllllll lttrfllti Illlfllbf. Al lhl lluld It lvrved lllla the Gyllndur. \hl Illlul lwvll lllvrlrl lll Il lhl llril llc llnlwlhl, lhll I |r1l\ lttllllg if lhl llttll rltlhll MIL lttddlnly nd\|nlN thu lrllllln ll lhll lhl Ill!! ll thl nllllnllol lllll llllrll ltlllf lltd 'Ill I the Rlllnll dw/ll, e|a|lN the Inrll, tvhureupnn lhlll lllrlllllll lrl Nnlllld ll M rlllll lllnllllll ll Il lily ll Ill fld. Eli tlllle the Ultlm, ¢\1m|rlx|N lhe glxhln. Nl. llllhh Ind llllllhhll l ll , rlulvll I Ill!! Il llllvlrl ll Ill will nts which Il ll\lf|l\||lld bv thl Illlrill nf llll lllvlll ll!!! Ill Khl llllhlll O lhl I rllfhllllhy ll In the lllltrlul lyltlm Un llrlcl at the llrulll ll dullrmlnld U lhl ull-I|N||a\|n|| Ind elllilq. \|I:lr l Nl! lilllllllll thl lllurll llrlul 0| tbl lllll n lyllum wlll he the nm: ll \hl¢ ll lhl lrlnlrlly llllnrlll llellllllll, Ill Illlll thl l||l¢|‘y nl lhl mavlmunl llll In rrllhnl, Il. lnllud ol the llllrlhtnl, \hl Nllllvtzlllng 1u|l\l ll lllltgll ill Ollrntlel ll he llml ll Irlncllll noel lhll lhl rlrlldlo ImD\|I|ll el tm nun Inna umm lllltllllnl. n but mum m -rm mm.: wnui rynnmnlnm 1| me mln-a u-mm mm nn me mural mlm mu »| in- mum. gation showed that no matter what medium is employed, be it air, hydrogen, mercury vapor, oil or a stream of electrons, the ehiciency is the same. It is a law very much __ mrs: --a- df v ' nw -- ' paw r :par ` ' 'lv/rvnv af' L u mu M M | wwf 6 'nd' -1- "%" mmf Flg. 3-Scheme of Clrcult Cnnnectlone In Te|I|'| Olclllltlun Transformer Shown In Flu. 1. The Secondary Clrcult Whlch Slips Into the Prlmary || Omltted. carry it to the lower level along any devious path, it is immaterial insofar as the amount of work is concerned, Fortunately how- ever, this drawback is not fatal as by proper proportioning of the resonant circuits an cfidellry of 85 [fur rvnl is attainaiblc. Since my early rnnnninccnwnt nf tln- in\'i-ntinn it has mnw into nni\»;r>;|l nsc :nnl \\nnn;ln ai revolntiun in many slcp;\rt|nci\\s. llnt ai still greater fnlurc awaits it. \Vhen in 1900 I obtained powerful discharges of 100 feet and flashed a current around the globe, I was reminded of the first tiny spark I oh- served in my Grand Street laboratory and was thrilled by sensations akin to those I felt when I discovered the running mag- nrlir fold.

I6 ELECTRICAL EXPERIMENTER May, I9 I9 OR a while I gave myself up entirely to the intense en- , joyntent ni picturing niacltines :tml tlcvising new forms, '* ' It was a mental state of happiness about as complete as I I . have ever known in lite, Ideas cainc in an uninterrupted stream and the only difficulty I had was to hold them fast. The pieces of apparatus I conceived were to me absoltttely real and tangible in every detail, even to the minutest marks and signs of wear. I delighted in imagining the motors constantly running, for in this \vay they presented to the mintl's eye a more fascinating sight. VVhen natural inclination tlctelnps into :\ pnssitimttu desire, one advances towards his goal in seven-league boots. ln less than two months I evolved virtually all the types of motors and mmlifi- cations of the system which are new itlentifietl with my natne. It was, perhaps, provitlenlial that the necessities of existence rom- manded a temporary halt to this consuming activity oi the mind. I came to Budapest prompted hy a premature report concerning the telephone enterprise and. as irony oi fate willed it, I had to accept a posi- tion as draftsman in the Central Telegraph Othce . of the Hungarian Gov- ‘ ernment at a salary - which I deem it my priv- ilege not to disclose! Fortunately, I soon won the interest of the 1n- spectnr-in-Chiel and was thereafter employed on calculations, designs and estimates in connection with new installations until the Telephone Ex- change was started, when I took charge of the same. The knowl- edge anrl practical expe- rience I gained in the course of this work was f” most valuable and the »\ employment gave me ample opportunities for the exercise of my in- ventive faculties. I made several improvements in the Central Station ap- paratus and perfected a telephone repeater or amplifier \vhich was never patented or public- ly described but would be creditable to me even today. In recognition of n\y elhcient assistance the organizer of the un- dertaking, Mr. Puskas, upon disposing of his T H i » \ L, 'Y s tmW,. .Q _i V1 , tot... 3».4~\ vm *U Q ni K1 A ?’“Q.Z$5‘?_f5°§E`°’E2E i §`;ass’s2§ie-I2a:- _ 5;-,~5Q;§,E3I :,.Egmr3_E: §-g_<3‘f,;; ~__:..~E“‘ ‘2 . ... , ---- _..=. . “5»‘aS=‘Si_xf:§§==.2 .=’;=E'~ 0;-5-E§E...:°.&-<§=`<=E~ '"5--2:5-E iz ~-*fe §’.Lgv\`:.°g-w5:§g.(’i»-1. _‘ f°"’7'»-.3§'5`;--5-°t_T._.ri‘: <§'sT%f»19is'-&P§:‘2=,; §=*&°“f°é'2”~“2és2 ":'v.;‘E°;;:,,§c..Z5'=-<» FE;-f' ag§°'=¢»,~g:-5,225 ‘ _.Q ,__: 0:11 _§w »,r' gg* *~\’U '- §§§5;p2§§;&5;S=§ F -éE`='e=?\°2:'g7~"¢:,,‘2':z E n --n."v-- “':' ve... Q_33,',,,gE ‘<__o;w -.vs - ~="~“-iE‘£5L‘4=>-~25'5-:fy 15:/19-r'°'<>f‘§u»>¢Kf‘n; “rm aJ""7L‘--vi:-"°`:|"v| "‘=:§,__,=E;`:-=¢5°‘:.;:Z‘, ~=__ Q : ____ -0 5loo5'g‘..§?*;:5‘§f.u»:= "l?.§,§_5,5'Eg-§§n‘3E,5"355==‘i'g5‘,9 °°:"'*¥"-5x‘5‘»- ,gon v°O2"“’ _..=._o=- »__.,, ..< ss5f»s=,,,<.-» rn_ o;5°:'-,t-g0w=‘-too" 5:12. m55...,°,;»-. _,og O f-;n¢_-_,_.___:»-< ._. E a=..=_e. : --~»==a-Sm;-=Sssf"“.,t’ no ;____of1'l3.»i:5=>‘ v- :-.-mv -\..., -_.`:'d€:.§§5\:.§'£r:'§ '.:.',=\;a`< Qv" 5 55" w1<5Ff=f=~§="""»~E »g:O5'@n>-__v: -».o n;.°,i,.,__nmg;‘,:,, Fr?- 1*-?~¥S9.¢Z“=~ 52°=:.e..,'-IEC* §‘.1§§=§=§---=2S~S=af»‘2'[email protected];>'=§ on/'~\é,,;, ! _V . - 1 ,L - av-e~v »:o.2~f‘ V l Y t. : p V / , ,ll I ‘~ i ul.” »_ » ', - ‘I ggi., i _ . 115 _ , ttf - 2 . ‘ .V r» ‘f _ _., - f ,a it ’ "" 7".,»x. , < ' , -.s f:_;»: \rt. - f f. ,§?;.4;;L~r<; < ___ ' "7t1;.'§'.'-“`xc_r _.i%QE’}'1i';_ ~ ~ f _< _ es .Q “*» " Zlgfiifild :**_f»\i" i" i-.gi i A M. .rtifygjflf .~ f.. ~»|t_ I *5f5'“€’@1ft§!t*i"~ Q‘§f_ t L il. , _ I hnsiness in Budapest, of- fcrvrl me :t pnsitimt in l’:n'is which I gladly ac- cepted. Fin. 1-Tenln Onelllntlon Trannformer (Tenla Coll) Presented hy Lord Kelvln Dl7fn|‘n the Drltlllt /\l|nuC|n\lc|\ lu All tlll, IBOT. T|\ll Bttlllll |\Y\t1 COMDIU( |l1l!rt|- '“¢|\¥| Only S Inches Hlnh. Developer] §l`wo Square Feat ot Streamarl Wlih Twink)/~ Five watts From the no Volt D. c. supply clreult. The Instrument contain: a Tesla Primary and Secondary. Condenser. and a Clrcult Controller. after there was some trouble with the lighting plant which has been i|\- stalled at the new rail- <~,»fyf.,,m, iv19_ :gy 1; P. ra ,411 fight. rf_.m~~1 Mr. 'I`r.rlr|'.r mix:/r.r _rt/zrtrd in /mr Frhrunry ixxnc

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