Phonograph?-?History?
The?first?great?invention?developed?by?Edison?in?Menlo?Park?was?the?tin?foil?phonograph.?While?working?to?improve?the?efficiency?of?a?telegraph?transmitter,?he?noted?that?the?tape?of?the?machine?gave?off?a?noise?resembling?spoken?words?when?played?at?a?high?speed.?This?caused?him?to?wonder?if?he?could?record?a?telephone?message.?He?began?experimenting?with?the?diaphragm?of?a?telephone?receiver?by?attaching?a?needle?to?it.?He?reasoned?that?the?needle?could?prick?paper?tape?to?record?a?message.?His?experiments?led?him?to?try?a?stylus?on?a?tinfoil?cylinder,?which,?to?his?great?surprise,?played?back?the?short?message?he?recorded,?"Mary?had?a?little?lamb."
The?word?phonograph?was?the?trade?name?for?Edison's?device,?which?played?cylinders?rather?than?discs.?The?machine?had?two?needles:?one?for?recording?and?one?for?playback.?When?you?spoke?into?the?mouthpiece,?the?sound?vibrations?of?your?voice?would?be?indented?onto?the?cylinder?by?the?recording?needle.?This?cylinder?phonograph?was?the?first?machine?that?could?record?and?reproduce?sound?created?a?sensation?and?brought?Edison?international?fame.
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Electricity?and?Lightbulb?-?History
Thomas?Edison's?greatest?challenge?was?the?development?of?a?practical?incandescent,?electric?light.?Contrary?to?popular?belief,?he?didn't?"invent"?the?lightbulb,?but?rather?he?improved?upon?a?50-year-old?idea.?In?1879,?using?lower?current?electricity,?a?small?carbonized?filament,?and?an?improved?vacuum?inside?the?globe,?he?was?able?to?produce?a?reliable,?long-lasting?source?of?light.?The?idea?of?electric?lighting?was?not?new,?and?a?number?of?people?had?worked?on,?and?even?developed?forms?of?electric?lighting.?But?up?to?that?time,?nothing?had?been?developed?that?was?remotely?practical?for?home?use.?Edison's?eventual?achievement?was?inventing?not?just?an?incandescent?electric?light,?but?also?an?electric?lighting?system?that?contained?all?the?elements?necessary?to?make?the?incandescent?light?practical,?safe,?and?economical.?After?one?and?a?half?years?of?work,?success?was?achieved?when?an?incandescent?lamp?with?a?filament?of?carbonized?sewing?thread?burned?for?thirteen?and?a?half?hours.?
There?are?a?couple?of?other?interesting?things?about?the?invention?of?the?light?bulb:?While?most?of?the?attention?was?on?the?discovery?of?the?right?kind?of?filament?that?would?work,?Edison?actually?had?to?invent?a?total?of?seven?system?elements?that?were?critical?to?the?practical?application?of?electric?lights?as?an?alternative?to?the?gas?lights?that?were?prevalent?in?that?day.?
These?were?the?development?of:?
1.the?parallel?circuit,?
2.a?durable?light?bulb,?
3.an?improved?dynamo,?
4.the?underground?conductor?network,?
5.the?devices?for?maintaining?constant?voltage,?
6.safety?fuses?and?insulating?materials,?and?
7.light?sockets?with?on-off?switches.?
Before?Edison?could?make?his?millions,?every?one?of?these?elements?had?to?be?invented?and?then,?through?careful?trial?and?error,?developed?into?practical,?reproducible?components.?The?first?public?demonstration?of?the?Thomas?Edison's?incandescent?lighting?system?was?in?December?1879,?when?the?Menlo?Park?laboratory?complex?was?electrically?lighted.?Edison?spent?the?next?several?years?creating?the?electric?industry.?
The?modern?electric?utility?industry?began?in?the?1880s.?It?evolved?from?gas?and?electric?carbon-arc?commercial?and?street?lighting?systems.?On?September?4,?1882,?the?first?commercial?power?station,?located?on?Pearl?Street?in?lower?Manhattan,?went?into?operation?providing?light?and?electricity?power?to?customers?in?a?one?square?mile?area;?the?electric?age?had?begun.?Thomas?Edison's?Pearl?Street?electricity?generating?station?introduced?four?key?elements?of?a?modern?electric?utility?system.?It?featured?reliable?central?generation,?efficient?distribution,?a?successful?end?use?(in?1882,?the?light?bulb),?and?a?competitive?price.?A?model?of?efficiency?for?its?time,?Pearl?Street?used?one-third?the?fuel?of?its?predecessors,?burning?about?10?pounds?of?coal?per?kilowatt?hour,?a?"heat?rate"?equivalent?of?about?138,000?Btu?per?kilowatt?hour.?Initially?the?Pearl?Street?utility?served?59?customers?for?about?24?cents?per?kilowatt?hour.?In?the?late?1880s,?power?demand?for?electric?motors?brought?the?industry?from?mainly?nighttime?lighting?to?24-hour?service?and?dramatically?raised?electricity?demand?for?transportation?and?industry?needs.?By?the?end?of?the?1880s,?small?central?stations?dotted?many?U.S.?cities;?each?was?limited?to?a?few?blocks?area?because?of?transmission?inefficiencies?of?direct?current?(dc).
The?success?of?his?electric?light?brought?Thomas?Edison?to?new?heights?of?fame?and?wealth,?as?electricity?spread?around?the?world.?His?various?electric?companies?continued?to?grow?until?in?1889?they?were?brought?together?to?form?Edison?General?Electric.?Despite?the?use?of?Edison?in?the?company?title?however,?he?never?controlled?this?company.?The?tremendous?amount?of?capital?needed?to?develop?the?incandescent?lighting?industry?had?necessitated?the?involvement?of?investment?bankers?such?as?J.P.?Morgan.?When?Edison?General?Electric?merged?with?its?leading?competitor?Thompson-Houston?in?1892,?Edison?was?dropped?from?the?name,?and?the?company?became?simply?General?Electric.
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