The incandescent lamp: who did what, and when (1812 to 1895)

As of 2026-10-02. Every event is a shared node (build/nodes/lamp-*.yaml) that holds the date, its basis and precision, the place where a source names one, and the sources; this file only says where each dot sits. Times are set to noon UTC and are drawn at day, month or year precision; the node's `date_basis` and, where the date is uncertain, its `window` say how the date was reached. A patent's grant date is used unless the label says filed. Events marked disputed have sources that disagree, as named in the detail. Claimed events with no dated record (Goebel 1854, Swan 1850s, de la Rue 1840) are not drawn as events; the earliest dated traces of the Goebel claim (1882) are. Places are given only where a source names them; the court rulings are placed at state level because the opinions do not name the sitting city.

Shape = kind of source: machine-recorded data a primary document an official statement a person's account a scholar's account a news report Style = status: 2+ sources agree one source sources differ our inference / time not reported the same event at another source's time Every dot is a link to its main source; the table lists all sources.

Panel A: 1810 to 1895 (one tick per five years)

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1810 1815 1820 1825 1830 1835 1840 1845 1850 1855 1860 1865 1870 1875 1880 1885 1890 1895 Time, UTC Britain (Davy, de Moleyns, King/Starr, Swan) Belgium and Germany Russia (Lodygin) Canada (Woodward and Evans) United States (Edison and rivals) Patent offices and courts 1. 1812: Davy's account of the carbon arc and the 2000-plate battery is in print (single, document). Davy, Elements of Chemical Philosophy, pp. 85-86: with the Royal Institution's battery of 2000 double plates, pieces of charcoal about an inch long and one sixth of an inch across, brought within a thirtieth or fortieth of an inch, gave 'a bright spark', and 'more than half the volume of the charcoal became ignited to whiteness'; drawn apart, 'a constant discharge' formed 'a most brilliant ascending arch of light' of at least four inches. The book gives no date for the experiment. An arc, not an incandescent lamp. The demonstration date (1808-1810) is not in the book.1 2. 21 Aug 1841: de Moleyns, British patent No. 9053 (single, document). Abridgment of British patent 9053 (A.D. 1841, August 21), Frederick de Moleyns, 'the production or developement of electricity, and the application of electricity for the attainment of illumination and motion'. Its second head is 'a means of generating the electric light, by constantly supplying the electrodes at their junction, with pulverized charcoal' from a tube; the electrodes are two coils of platinum wire, the lower enclosing spongy platinum, and 'the whole arrangement is enclosed in an exhausted glass globe'. The abridgment does not use the words 'glow' or 'incandescent'. The Supreme Court (1895) calls it a patent for an incandescent electric lamp using finely pulverized boxwood charcoal or plumbago. The full specification was not read. Earliest patent found for an electric light in an enclosed globe (not shown to be heated or glowing); the search was not exhaustive (see lamp-earliest-patent).2 3. 4 Nov 1845: King (a communication), British patent No. 10,919 (single, document). Abridgment of British patent 10,919 (A.D. 1845, November 4), Edward Augustin King, 'a communication': 'The application of continuous metallic and carbon conductors, intensely heated by the passage of a current of electricity, to the purposes of illumination.' A current is passed through thin platinum foil under a glass shade; where carbon is used it is to be enclosed in a 'Torricellian' vacuum (the abridgment's scan is damaged at that phrase; 40 F. 21 quotes the specification: 'When carbon is used, it becomes necessary ... to exclude from it air and moisture ... it should be inclosed in a Torricellian vacuum'). The abridgment does not name Starr; Judge Colt (54 F. 678, 1893) says 'Starr suggested in the King patent a lamp composed of a thin pencil of carbon, inclosed in a Torricellian vacuum'. The full specification was not read.3 11. Dec 1878: Swan describes a carbon-rod lamp that blackened its globe (Newcastle Chemical Society) (single, document). Chemical News 39: at the Newcastle Chemical Society meeting, Mr. J. W. Swan in the chair (the meeting 'immediately preceding Christmas'), the chairman 'described an experiment he had recently performed on the production of light, by passing a current of electricity through a slender rod of carbon enclosed in an exhausted globe', current from a Siemens dynamo-electric machine 'of the second or 6000 candle size'. The rod 'glow[ed] with great splendour', the glass 'became coated with a sooty deposit on its inside', and the rod 'became curved to the form of a bow, as if from softening'. B. S. Proctor's note in the same volume (read 27 Mar 1879) says that 'at our meeting in December, 1878, Mr. J. W. Swan exhibited an electric lamp ... which had broken down'. The report prints no day. The `time` is the middle of the December 1878 window; no source read gives a day (an earlier 18 Dec came from secondary summaries that were not kept). A rod that blackened its globe; no lasting lamp.11 4. 27 Feb 1858: Jobard's communication on de Changy's lamps, as printed by Fontaine (single, document). Fontaine (1878) prints a communication he says 'M. Jobart' made 'to the Academy of Sciences on the 27th of February, 1858'. In it, in de Changy's laboratory, 'a dozen small miner's lamps' were in circuit; 'the lamps, which are enclosed in hermetically sealed glass tubes', are lit 'by the incandescence of platinum'; one 'was lit in the hollow of my hand'. Fontaine places de Changy 'in Belgium' and Jobard 'of Brussels'. Whether the tubes were exhausted is not stated in the passage. The Academy's own report (Comptes rendus) was not read. Known only through Fontaine's 1878 quotation; Fontaine is the only channel for this and for Lodygin.4 Kommersant (2024) gives 1872 for the first demonstration; Fontaine (1878) gives 1873. 1872 6. 1872-73: Lodygin's carbon-rod lamps (reported to the St Petersburg Academy) (disputed, document). Fontaine (1878): 'in 1873 a Russian physicist, M. Lodyguine, resuscitated both [lighting by incandescence and its principle], and invented a new lamp'. The St Petersburg Academy's report by Wild, quoted by Fontaine, says Lodygin replaced platinum with small carbon bars heated in a hermetically sealed glass receiver from which oxygen is expelled; Fontaine adds 'Nothing is less practical nor less studied than the apparatus of this inventor.' Kommersant (2024) gives 1872 for the first demonstration and says early samples lasted 30-40 minutes. Fontaine judges the apparatus impractical.6! 7. 1874: St Petersburg Academy awards Lodygin the Lomonosov prize (single, official). Fontaine (1878): 'In 1874, the St. Petersburg Academy of Sciences awarded a high prize to M. Lodyguine', on a report by M. Wild, director of the Imperial Observatory, which finds him 'worthy ... to obtain the Lomonossow prize'. The amount is not given ('a high prize'). The Academy's report itself was not read. Prize per Fontaine; the amount is not given.7 8. 11 Jul 1874: Lodygin is issued Russian privilege No. 1619 (priority dated from 2 Oct 1872) (single, official). Kommersant (St Petersburg, 11 Jul 2024), marking 150 years: on 11 July 1874 the home patent office issued Lodygin privilege No. 1619, 'interestingly' with the priority dated retroactively, from 2 October 1872; the article also says he petitioned for a privilege in 1872 and, in another passage, that the first patent for an incandescent lamp 'was received' that day. One later newspaper history; no scan of the privilege. LOW CONFIDENCE (owner decision): the number, the 11 July 1874 date and the backdated priority all come from this one newspaper history with no scan of the privilege; the same page says the Russian patent came 'only a year' after the 1872 petition, which does not fit a July 1874 grant, so these details are unverified. One newspaper history (Kommersant 6822124), no scan; the same page says the Russian patent came only a year after the 1872 petition, which does not fit July 1874: number and date unverified, low confidence.8 9. 3 Aug 1874: Woodward and Evans, Canadian patent No. 3,738 (single, document). Scientific American, 12 Sep 1874, 'Canadian patents granted August 3 to 13, 1874': '3,738. H. Woodward and M. Evans, Toronto, Ont. Improvements on the art or process of obtaining artificial [light] by means of electricity, called Woodward and Evans' Electric Light. Aug. 3, 1874.' (The OCR is damaged at the number and at the word after 'artificial'; read and corrected by hand.) The Canadian specification was not read. The Canadian specification was not read.9 10. 29 Aug 1876: Woodward, US patent 181,613 (single, official). US 181,613, 'Improvement in Electric Lights', Henry Woodward 'of the city of Toronto, county of York, Province of Ontario', application filed 4 Jan 1875, dated 29 Aug 1876; assigned by mesne assignments to R. M. Wells, T. R. Fuller and E. Heimrod 'of same place' and C. H. Woodward of Lindsay, Canada. A piece of carbon is fitted with electrodes in a globe; the air is exhausted and the globe 'filled with a rarefied gas that will not unite chemically with the carbon when hot'; the claim is the carbon in combination with a lamp vessel filled with such a gas. No assignment to Edison is shown on the patent. No document of an Edison purchase was found.10 5. 9 May 1865: Henry Goebel of New York, US patent 47,632 (sewing-machine hemmer) (single, official). US 47,632, 'Improvement in Hemmers for Sewing-Machines', Henry Goebel 'of the city, county, and State of New York', dated 9 May 1865. The patent is for a hemmer guide and has nothing to do with lamps; it shows only that Goebel held a patent in New York in 1865. Shows only that Goebel held a patent in 1865; nothing about lamps.5 12. 22 Oct 1879: Edison's laboratory thread lamp burns 13 1/2 hours (single, document). Edison Papers, Doc. 1831 (Batchelor's notebook entry, '[Menlo Park,] Oct 22nd 1879 9 A.M.'): 'some very interesting experiments on straight carbons made from cotton thread'; 'a piece of 6 cord thread No 24 ... about 13 thousandths in thickness', carbonised in a closed chamber and put 'in vacuo'; 'it gave a light equal to about 1/2 candle 18 cells', resistance 113 ohms at starting, afterwards 140. 'No 9: On from 1.30 AM till 3 pm 13 1/2 hour and was then raised to 3 gas jets for 1 hour then cracked glass & busted.' The Papers' essay 'The Carbon-Filament Lamp' says the same. Clock times are the notebook's own; no time zone is given. The notebook image (N-79-07-31, p. 105) was not opened. 13 1/2 hours, not 40.12 13. 27 Jan 1880: Edison's US patent 223,898 'Electric-Lamp' granted (single, official). US 223,898, 'Electric-Lamp', Thomas Alva Edison 'of Menlo Park, in the State of New Jersey', patented 27 Jan 1880. Claim 1 is a carbon filament of high resistance; claim 2 carbon filaments in a receiver made entirely of glass and exhausted of air, with the conductors passing through the glass; the specification names a mercury pump. The place is the inventor's address as printed (the scan's OCR of the address is poor; 'Menlo Park, New Jersey' is read from it), not where the patent issued. Filed 4 Nov 1879 (node lamp-1879-11-04-edison-files-patent-223898).13 14. 4 Sep 1882: Edison Electric Illuminating Company turns on light in the first Pearl Street district (single, media). New-York Tribune, 5 Sep 1882, p. 8: 'The company at 3 p.m. turned on the electric light in part of the first of the districts in which this kind of illumination is to be distributed from a common centre'; the 'central station ... is at ... Pearl-st., just below Fulton-st.'; the report is of 'yesterday' (Monday 4 Sep). Johnson is quoted as saying 'about one-third of the district' was lit. The company's own records were not read. Generation, wiring and metering were the commercial invention; the lamp was one part.14 15. Early 1885: Commissioner of Patents decides the Edison-Sawyer-Man interference for Sawyer and Man (single, official). 40 F. 21: Edison applied in December 1879 (11 Dec) and Sawyer and Man on 9 January 1880; 'in September, 1880, an interference was declared between the two applications' over carbon made from paper; 'The case was not finally decided until the beginning of 1885.' Broadnax, the attorney who prepared the Sawyer-Man application, is quoted as speaking of 'the decision of the commissioner of patents of the interference, awarding priority of invention to Sawyer and Man' and puts the amendments that followed in February and March 1885. The Commissioner's decision itself was not read.15 16. 5 Oct 1889: Circuit court dismisses the Sawyer-Man patent suit (Consolidated Electric Light Co. v. McKeesport Light Co.) (single, official). 40 F. 21 (C.C.W.D. Pa., 5 Oct 1889), Bradley J.: the Sawyer-Man patent (granted 12 May 1885; application filed 9 Jan 1880), apart from its third claim which was not in issue, is held to amount to 'the broad claim of the exclusive use, in incandescing lamps, of all carbons made of fibrous or textile materials' (headnote), and is held invalid; the court was 'not at all satisfied that Sawyer and Man ever made, and reduced to practical operation, any such invention', and found that the specification had been changed in 1885, after Edison's work was published, from the arched carbon to all fibrous carbons. 'The bill must be dismissed.'16 17. July 1891: Wallace J. holds Edison's claim 2 valid and infringed (47 F. 454) (reported, official). 47 F. 454 (C.C.S.D.N.Y., 1891), Wallace J.: Edison was 'the first to make a carbon of materials and by a process which was especially designed to impart high specific resistance to it', 'the first to make a carbon in the special form for the special purpose of imparting to it high total resistance', and 'the first to combine such a burner with the necessary adjuncts of lamp construction to prevent its disintegration and give it sufficiently long life'; 'By doing these things he made a lamp which was practically operative and successful'. The reporter prints '1891' only; 57 F. 616 says the judgment was obtained in July 1891.17 18. 4 Oct 1892: Court of Appeals (2d Cir.) affirms Wallace J. on Edison's second claim (single, official). 52 F. 300 (C.C.A. 2d Cir., 4 Oct 1892), Lacombe J.: the second claim of patent 223,898 (carbon filament in an all-glass exhausted receiver with the conductors through the glass) is sustained and the decree affirmed. On the patent's term the court holds the patent in suit not affected by the loss of a Swedish patent (directly, or through Canadian patent No. 10,654 of 17 Nov 1879) and the Commissioner's attempted 'certificate of correction' limiting the term 'wholly void'. The decree is 'affirmed, with costs'.18 19. 18 Feb 1893: Colt J. (D. Mass.) grants Edison an injunction, finding Goebel's 1854 lamp 'extremely improbable' (single, official). 54 F. 678, on a motion for a preliminary injunction, on about forty affidavits for Goebel and others against: 'It is extremely improbable that Henry Goebel constructed a practical incandescent lamp in 1854'; whether he made lamps 1, 2 and 3 'it is not necessary to determine. The weight of evidence on this motion is in the direction that he made these lamps, or lamps similar in general appearance ... But assuming they were made, they do not anticipate the invention of Edison. At most they were experimental toys'; of lamp No. 4: 'It is simply impossible, under the circumstances, to believe that a lamp so constructed could have been made by Goebel before 1872.' The court applied the rule that a new defence against a patent already upheld must be proved convincingly. Injunction granted. Preliminary ruling on affidavits.19 20. 21 Apr 1893: Hallett J. (E.D. Mo.) refuses an injunction on bond: 'a fair preponderance of testimony' for Goebel (single, official). 56 F. 496, on a motion for a preliminary injunction: Goebel 'does not appear to be an adventurer or an impostor'; 'there is a fair preponderance of testimony in support of the Goebel claim'; 'a defense which puts the case in doubt is sufficient to defeat the application'. Judge Hallett says he does 'not feel compelled to accept the opinion of the court in' the Boston case. The injunction 'will therefore be refused, if the respondents shall give a bond in the sum of $20,000'. The ruling does not decide the Goebel claim finally. Preliminary ruling on affidavits; the other way.20 21. 20 Jul 1893: Seaman J. (E.D. Wis.) grants Edison an injunction, following Boston and disapproving St. Louis (single, official). 57 F. 616, on a motion for a preliminary injunction against lamp makers at Oconto, Wis.: the headnote states the rule that a new defence against a patent upheld 'after protracted and expensive litigation' can be defeated only by 'convincing proof as will raise a presumption that it would have defeated the patent', every reasonable doubt being resolved against it; 54 F. 678 followed, 56 F. 496 'disapproved'. 'I cannot find that [the new affidavits] remove any of the doubts above noted.' Injunction granted. Preliminary ruling; the Seventh Circuit appeal below is the same case.21 22. 1 May 1894: Seventh Circuit affirms the Wisconsin injunction (the appeal in the same case) (single, official). 61 F. 834 (7th Cir., 1 May 1894), on appeal from the preliminary injunction in 57 F. 616: the right of an owner of a patent upheld after protracted litigation to a preliminary injunction can be defeated only by a new defence proved convincingly; the court says that, 'without designing to suggest what result should be reached upon final hearing', the story of Goebel's early lamps 'is surrounded by such an atmosphere of improbability' that until sifted and sustained at final hearing it ought not to invade the patent holder's monopoly. This is the same case on appeal reviewing a discretionary preliminary ruling, not a fourth case.22 23. 11 Nov 1895: Supreme Court affirms the dismissal of the Sawyer-Man suit (The Incandescent Lamp Patent) (single, official). 159 U.S. 465 (argued 29-30 Oct 1894, decided 11 Nov 1895; the scan's heading misprints the year as '1815'), Brown J.: 'we are all agreed that the claims of this patent, with the exception of the third [carbonised paper], are too indefinite to be the subject of a valid monopoly'; the question of priority 'becomes unnecessary'; 'the decree of the Circuit Court is Affirmed'. The Court also recounts Edison's search among 'about forty different kinds of bamboo' and says he 'despatched a man to Japan'. Holds the Sawyer-Man claims other than the third too indefinite; does not decide priority.23

Panel B: 1878 to 1885, the race and the patent fight (one tick per year)

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1878 1879 1880 1881 1882 1883 1884 1885 1886 Time, UTC Britain (Davy, de Moleyns, King/Starr, Swan) United States (Edison and rivals) Newspapers Patent offices and courts 24. Dec 1878: Swan describes a carbon-rod lamp that blackened its globe (Newcastle Chemical Society) (single, document). Chemical News 39: at the Newcastle Chemical Society meeting, Mr. J. W. Swan in the chair (the meeting 'immediately preceding Christmas'), the chairman 'described an experiment he had recently performed on the production of light, by passing a current of electricity through a slender rod of carbon enclosed in an exhausted globe', current from a Siemens dynamo-electric machine 'of the second or 6000 candle size'. The rod 'glow[ed] with great splendour', the glass 'became coated with a sooty deposit on its inside', and the rod 'became curved to the form of a bow, as if from softening'. B. S. Proctor's note in the same volume (read 27 Mar 1879) says that 'at our meeting in December, 1878, Mr. J. W. Swan exhibited an electric lamp ... which had broken down'. The report prints no day. The `time` is the middle of the December 1878 window; no source read gives a day (an earlier 18 Dec came from secondary summaries that were not kept).24 Histelec gives 17 Jan 1879; Newcastle University and the Linda Hall Library give 3 Feb (secondary, not read). 17 Jan 25. About two years before 20 Oct 1880: Swan shows his 'little lamp' at the Lit and Phil (date unknown; 17 Jan or 3 Feb 1879 per secondary pages) (disputed, witness). Swan, lecture of 20 Oct 1880 (Chemical News 42, pp. 227, 230): he began by referring to 'my last lecture on Electric Lighting, almost two years ago', and later said 'there are many here who will remember this little lamp, which I showed here two years ago in action', 'composed entirely of three substances, namely, glass, platinum, and carbon'. No 1879 report of the showing was found. The dates 3 February 1879 (Newcastle University; Linda Hall Library) and 17 January 1879 (Histelec) are from secondary pages that were seen only as search summaries. The `time` is the middle of the window; the 3 Feb and 17 Jan 1879 dates are from secondary pages seen only as search summaries (the alternative marker shows 17 Jan) and are not used as the date. Swan's own 1880 reference; date uncertain; no 1879 report found.25! 32. 1880: Armstrong lights Cragside with Swan's incandescent lamps (single, witness). IET Archives blog (2023), two passages: 'the arc lamps were replaced by Armstrong in 1880 with 45 incandescent lamps'; and Armstrong's letter to the editor of The Engineer of 17 January 1881 was written 'shortly after he utilised Joseph Swan's newly invented incandescent light bulbs'. That the 1880 lamps were Swan's is the blog's joining of the two passages. The letter itself was not read. The blog's 'first house in the world' is not used. Armstrong's 1881 letter not read.32 33. 20 Oct 1880: Swan lectures on electric lighting and disputes Edison's priority on carbonised paper (single, witness). Chemical News 42 (5 Nov 1880): J. W. Swan, lecture to the Newcastle-upon-Tyne Literary and Philosophical Society, 20 October 1880. He describes an experiment 'about twenty years ago' with a carbonised paper arch in a vacuum that 'became red-hot' and bent until it broke; calls it 'the very first instance in which carbonised paper was ever used in the construction of an incandescent electric lamp'; and says a Scribner's article's statement that Edison was first to use carbonised paper 'is incorrect'. It is Swan's own account, given while he disputed priority with Edison. Swan's own account while disputing priority.33 35. 28 Dec 1881: the Savoy Theatre stage is lit with Swan lamps at a performance of Patience (single, media). The Times, Thursday 29 Dec 1881 (Gilbert and Sullivan Archive transcription): 'An interesting experiment was made at a performance of Patience yesterday afternoon, when the stage was for the first time lit up by the electric light, which has been used in the auditorium ever since the opening of the Savoy Theatre.' 'The Swan incandescent lamps were used.' The original page was not compared. The report is of an experiment at one performance, not of lamps in regular use. Via transcription; the original Times page was not compared.35 43. Oct 1883: Edison and Swan United Electric Light Company formed by merger (single, official). Edison Papers company page: 'established in October 1883 as the result of a merger between the Edison Electric Light Company, Ltd. and the Swan United Electric Light Company, Ltd.' No day is given.43 26. 22 Oct 1879: Edison's laboratory thread lamp burns 13 1/2 hours (single, document). Edison Papers, Doc. 1831 (Batchelor's notebook entry, '[Menlo Park,] Oct 22nd 1879 9 A.M.'): 'some very interesting experiments on straight carbons made from cotton thread'; 'a piece of 6 cord thread No 24 ... about 13 thousandths in thickness', carbonised in a closed chamber and put 'in vacuo'; 'it gave a light equal to about 1/2 candle 18 cells', resistance 113 ohms at starting, afterwards 140. 'No 9: On from 1.30 AM till 3 pm 13 1/2 hour and was then raised to 3 gas jets for 1 hour then cracked glass & busted.' The Papers' essay 'The Carbon-Filament Lamp' says the same. Clock times are the notebook's own; no time zone is given. The notebook image (N-79-07-31, p. 105) was not opened.26 27. 4 Nov 1879: Edison applies for the patent that issues as 223,898 (reported, official). 40 F. 21 (Bradley J.): Edison's patent 'applied for November 4, 1879, and issued January 27, 1880' (the opinion's number is printed 228,898 in the scan, a misprint). The patent, in the scan read, is signed 'this 1st day of November, A.D. 1879', and the Edison Papers' note says Edison 'executed' the application on 1 November. The application file was not read.27 28. By 16 Nov 1879: Edison's laboratory has 'the first lamp that answers the purpose' (carbonised card) (single, document). Edison Papers essay 'The Carbon-Filament Lamp': 'By November 16, however, they had "the first lamp that answers the purpose we have wished. It is cheap much more so than we even hoped to have"', a horseshoe of charred paper cut from common card board, 'sealed in a glass bulb and the air exhausted'. The essay says 'By November 16'; the document it quotes was not opened.28 31. March 1880: Latimer begins work for Maxim at the U.S. Electric Lighting Company in Bridgeport (single, analysis). Queens Borough Public Library essay 'Inventing a Better Life: Latimer's Technical Career' (hosted by the Edison Papers): in Bridgeport, Connecticut, Latimer became 'an employee of Hiram Stevens Maxim, then chief engineer at the U.S. Electric Lighting Company'; he began there 'March, 1880'. The essay calls the company 'one of Edison's competitors' and says it moved to Brooklyn in 1880. A secondary account; Latimer's logbook and the company's records were not read. Secondary account (Queens Library essay hosted by the Edison Papers).31 34. 13 Sep 1881: Nichols and Latimer, US patent 247,097 'Electric Lamp' (single, official). US 247,097, 'Electric Lamp', Joseph V. Nichols of Brooklyn and Lewis H. Latimer 'of the city, county, and State of New York', application filed 18 April 1881, dated 13 Sep 1881: 'Improvements in Incandescent Electric Lamps' in which the carbon strip is secured to the metallic wires, 'more especially ... the method of mounting the carbons or connecting them with the wires': wires pass through perforated ends of the carbon strip and are bent over into contact with it.34 36. 17 Jan 1882: Latimer, US patent 252,386 'Process of Manufacturing Carbons' (single, official). US 252,386, Lewis H. Latimer 'of New York, N. Y., assignor to the United States Electric Lighting Company, of same place'; application filed 19 February 1881, dated 17 January 1882; blanks are carbonised inside envelopes so that they do not stick, break or warp. The patent does not describe the company or its relation to Edison. Assigned to the United States Electric Lighting Company.36 37. Early 1882: counsel Curtis first hears Goebel's story (lamps 'as early as about 1850') (single, witness). 54 F. 678, summarising Leonard E. Curtis's affidavit: he 'first heard of Henry Goebel in the early part of 1882', and Goebel told him he 'had made incandescent lamps like Edison's as early as about 1850', used 'for laboratory experiments' and not continued 'for more than a year or two after 1850'. Curtis inquired again in 1892 (Sawyer-Man injunction motion) and the defence was put forward in the 1893 suits.37 38. May 1882: Dickerson and Dickerson tell Edison's lawyer Eaton of Goebel's claimed lamps (single, witness). 54 F. 678, summarising Sherburne B. Eaton's affidavit: 'in May, 1882, the law firm of Dickerson & Dickerson called his attention to the alleged inventions of Henry Goebel'; Goebel's representative was William C. Dreyer; the Edison company's executive committee 'decided that Goebel had nothing worth buying'.38 39. 1882: Dreyer takes a paid option on Goebel's electric-lighting inventions (single, witness). 54 F. 678, summarising William G. Dreyer's affidavit: 'in 1882 he did procure from [Goebel] an option for three months of all his inventions relating to electric lighting' for $500, extended for three months for another $425. Goebel said he had made small incandescent lamps called the 'fiddle bow'; Dreyer 'made every effort to find one, but never succeeded'. No month is given.39 40. 4 Sep 1882: Edison Electric Illuminating Company turns on light in the first Pearl Street district (single, media). New-York Tribune, 5 Sep 1882, p. 8: 'The company at 3 p.m. turned on the electric light in part of the first of the districts in which this kind of illumination is to be distributed from a common centre'; the 'central station ... is at ... Pearl-st., just below Fulton-st.'; the report is of 'yesterday' (Monday 4 Sep). Johnson is quoted as saying 'about one-third of the district' was lit. The company's own records were not read.40 41. 24 Oct 1882: Goebel's US patent 266,358 'Electric Incandescent Lamp' (a lamp-socket detail) (single, official). US 266,358, Henry Goebel 'of the city, county, and State of New York', assignor of one-half to John W. Kulenkamp; application filed 23 January 1882, dated 24 October 1882: an electric vacuum-lamp in which the carbon conductor is secured in flattened, spirally coiled ends of the lead-in wires and cemented. Both claims are for the sockets.41 42. 28 Nov 1882: Goebel's son offers the Edison company his father's inventions for $20,000 (single, witness). 54 F. 678, summarising Sherburne B. Eaton's affidavit: 'On November 28, 1882, Henry Goebel, Jr., called upon him ... and made another offer to sell the inventions and good will of his father, naming the price of $20,000'; on 12 December 1882 he 'was informed that the company did not wish to buy'. This is not the earliest trace of the Goebel claim: Curtis (early 1882), the Dickersons' approach (May 1882) and Dreyer's option (1882) are earlier.42 29. 21 Dec 1879: NY Herald announces Edison's light and a New Year's Eve exhibition (single, media). New York Herald, 21 Dec 1879, p. 5, 'Edison's Light' (headings include 'A scrap of paper' and 'Success in a cotton thread'): 'The near approach of the first public exhibition of Edison's long looked for electric light, announced to take place on New Year's Eve at Menlo Park'. No byline is visible in the scan.29 30. 30-31 Dec 1879: crowds at Menlo Park see Edison's lights; Edison calls the announcement unauthorised (reported, media). New York Herald, 31 Dec 1879 (dateline 'Menlo Park, N. J., Dec. 30'): Menlo Park 'thronged with visitors' all day; sixty lights; 'the Inventor has fixed no day for a general inspection by the public at large'. New-York Tribune, 1 Jan 1880: 'The unauthorized announcement' that the lights would be exhibited 'drew scores of persons to that place last evening' (31 Dec); Edison 'disclaimed any intention of giving any formal exhibition'; 'between fifty and sixty lights burning'; headline 'No public exhibition promised or given' (the headline's OCR is damaged and is read as that). Contested whether this was a public exhibition (lamp-menlo-park-dec-1879).30 44. Early 1885: Commissioner of Patents decides the Edison-Sawyer-Man interference for Sawyer and Man (single, official). 40 F. 21: Edison applied in December 1879 (11 Dec) and Sawyer and Man on 9 January 1880; 'in September, 1880, an interference was declared between the two applications' over carbon made from paper; 'The case was not finally decided until the beginning of 1885.' Broadnax, the attorney who prepared the Sawyer-Man application, is quoted as speaking of 'the decision of the commissioner of patents of the interference, awarding priority of invention to Sawyer and Man' and puts the amendments that followed in February and March 1885. The Commissioner's decision itself was not read.44

Events (numbers match the diagram)

#When (UTC)WhatStatusSources
11812 (year only)1812: Davy's account of the carbon arc and the 2000-plate battery is in print
Davy, Elements of Chemical Philosophy, pp. 85-86: with the Royal Institution's battery of 2000 double plates, pieces of charcoal about an inch long and one sixth of an inch across, brought within a thirtieth or fortieth of an inch, gave 'a bright spark', and 'more than half the volume of the charcoal became ignited to whiteness'; drawn apart, 'a constant discharge' formed 'a most brilliant ascending arch of light' of at least four inches. The book gives no date for the experiment. An arc, not an incandescent lamp. The demonstration date (1808-1810) is not in the book.		single documentn:lamp-1812-davy-publishes-carbon-arc:0
221 Aug 1841 (date only)21 Aug 1841: de Moleyns, British patent No. 9053
Abridgment of British patent 9053 (A.D. 1841, August 21), Frederick de Moleyns, 'the production or developement of electricity, and the application of electricity for the attainment of illumination and motion'. Its second head is 'a means of generating the electric light, by constantly supplying the electrodes at their junction, with pulverized charcoal' from a tube; the electrodes are two coils of platinum wire, the lower enclosing spongy platinum, and 'the whole arrangement is enclosed in an exhausted glass globe'. The abridgment does not use the words 'glow' or 'incandescent'. The Supreme Court (1895) calls it a patent for an incandescent electric lamp using finely pulverized boxwood charcoal or plumbago. The full specification was not read. Earliest patent found for an electric light in an enclosed globe (not shown to be heated or glowing); the search was not exhaustive (see lamp-earliest-patent).		single documentn:lamp-1841-08-21-de-moleyns-patent-9053:0, n:lamp-1841-08-21-de-moleyns-patent-9053:1
304 Nov 1845 (date only)4 Nov 1845: King (a communication), British patent No. 10,919
Abridgment of British patent 10,919 (A.D. 1845, November 4), Edward Augustin King, 'a communication': 'The application of continuous metallic and carbon conductors, intensely heated by the passage of a current of electricity, to the purposes of illumination.' A current is passed through thin platinum foil under a glass shade; where carbon is used it is to be enclosed in a 'Torricellian' vacuum (the abridgment's scan is damaged at that phrase; 40 F. 21 quotes the specification: 'When carbon is used, it becomes necessary ... to exclude from it air and moisture ... it should be inclosed in a Torricellian vacuum'). The abridgment does not name Starr; Judge Colt (54 F. 678, 1893) says 'Starr suggested in the King patent a lamp composed of a thin pencil of carbon, inclosed in a Torricellian vacuum'. The full specification was not read.		single documentn:lamp-1845-11-04-king-starr-patent-10919:0, n:lamp-1845-11-04-king-starr-patent-10919:1, n:lamp-1845-11-04-king-starr-patent-10919:2
427 Feb 1858 (date only)27 Feb 1858: Jobard's communication on de Changy's lamps, as printed by Fontaine
Fontaine (1878) prints a communication he says 'M. Jobart' made 'to the Academy of Sciences on the 27th of February, 1858'. In it, in de Changy's laboratory, 'a dozen small miner's lamps' were in circuit; 'the lamps, which are enclosed in hermetically sealed glass tubes', are lit 'by the incandescence of platinum'; one 'was lit in the hollow of my hand'. Fontaine places de Changy 'in Belgium' and Jobard 'of Brussels'. Whether the tubes were exhausted is not stated in the passage. The Academy's own report (Comptes rendus) was not read. Known only through Fontaine's 1878 quotation; Fontaine is the only channel for this and for Lodygin.		single documentn:lamp-1858-02-27-jobard-reports-de-changy-lamps:0
509 May 1865 (date only)9 May 1865: Henry Goebel of New York, US patent 47,632 (sewing-machine hemmer)
US 47,632, 'Improvement in Hemmers for Sewing-Machines', Henry Goebel 'of the city, county, and State of New York', dated 9 May 1865. The patent is for a hemmer guide and has nothing to do with lamps; it shows only that Goebel held a patent in New York in 1865. Shows only that Goebel held a patent in 1865; nothing about lamps.		single officialn:lamp-1865-05-09-goebel-sewing-machine-hemmer-patent:0
61873 (year only)1872-73: Lodygin's carbon-rod lamps (reported to the St Petersburg Academy)
Fontaine (1878): 'in 1873 a Russian physicist, M. Lodyguine, resuscitated both [lighting by incandescence and its principle], and invented a new lamp'. The St Petersburg Academy's report by Wild, quoted by Fontaine, says Lodygin replaced platinum with small carbon bars heated in a hermetically sealed glass receiver from which oxygen is expelled; Fontaine adds 'Nothing is less practical nor less studied than the apparatus of this inventor.' Kommersant (2024) gives 1872 for the first demonstration and says early samples lasted 30-40 minutes. Fontaine judges the apparatus impractical.
Other-source time: Kommersant (2024) gives 1872 for the first demonstration; Fontaine (1878) gives 1873.		disputed documentn:lamp-1873-lodygin-carbon-rod-lamps:0, n:lamp-1873-lodygin-carbon-rod-lamps:1
71874 (year only)1874: St Petersburg Academy awards Lodygin the Lomonosov prize
Fontaine (1878): 'In 1874, the St. Petersburg Academy of Sciences awarded a high prize to M. Lodyguine', on a report by M. Wild, director of the Imperial Observatory, which finds him 'worthy ... to obtain the Lomonossow prize'. The amount is not given ('a high prize'). The Academy's report itself was not read. Prize per Fontaine; the amount is not given.		single officialn:lamp-1874-lomonosov-prize-lodygin:0
811 Jul 1874 (date only)11 Jul 1874: Lodygin is issued Russian privilege No. 1619 (priority dated from 2 Oct 1872)
Kommersant (St Petersburg, 11 Jul 2024), marking 150 years: on 11 July 1874 the home patent office issued Lodygin privilege No. 1619, 'interestingly' with the priority dated retroactively, from 2 October 1872; the article also says he petitioned for a privilege in 1872 and, in another passage, that the first patent for an incandescent lamp 'was received' that day. One later newspaper history; no scan of the privilege. LOW CONFIDENCE (owner decision): the number, the 11 July 1874 date and the backdated priority all come from this one newspaper history with no scan of the privilege; the same page says the Russian patent came 'only a year' after the 1872 petition, which does not fit a July 1874 grant, so these details are unverified. One newspaper history (Kommersant 6822124), no scan; the same page says the Russian patent came only a year after the 1872 petition, which does not fit July 1874: number and date unverified, low confidence.		single officialn:lamp-1874-07-11-lodygin-russian-privilege:0
903 Aug 1874 (date only)3 Aug 1874: Woodward and Evans, Canadian patent No. 3,738
Scientific American, 12 Sep 1874, 'Canadian patents granted August 3 to 13, 1874': '3,738. H. Woodward and M. Evans, Toronto, Ont. Improvements on the art or process of obtaining artificial [light] by means of electricity, called Woodward and Evans' Electric Light. Aug. 3, 1874.' (The OCR is damaged at the number and at the word after 'artificial'; read and corrected by hand.) The Canadian specification was not read. The Canadian specification was not read.		single documentn:lamp-1874-08-03-woodward-evans-canadian-patent:0
1029 Aug 1876 (date only)29 Aug 1876: Woodward, US patent 181,613
US 181,613, 'Improvement in Electric Lights', Henry Woodward 'of the city of Toronto, county of York, Province of Ontario', application filed 4 Jan 1875, dated 29 Aug 1876; assigned by mesne assignments to R. M. Wells, T. R. Fuller and E. Heimrod 'of same place' and C. H. Woodward of Lindsay, Canada. A piece of carbon is fitted with electrodes in a globe; the air is exhausted and the globe 'filled with a rarefied gas that will not unite chemically with the carbon when hot'; the claim is the carbon in combination with a lamp vessel filled with such a gas. No assignment to Edison is shown on the patent. No document of an Edison purchase was found.		single officialn:lamp-1876-08-29-woodward-us-patent-181613:0
11Dec 1878 (month only)Dec 1878: Swan describes a carbon-rod lamp that blackened its globe (Newcastle Chemical Society)
Chemical News 39: at the Newcastle Chemical Society meeting, Mr. J. W. Swan in the chair (the meeting 'immediately preceding Christmas'), the chairman 'described an experiment he had recently performed on the production of light, by passing a current of electricity through a slender rod of carbon enclosed in an exhausted globe', current from a Siemens dynamo-electric machine 'of the second or 6000 candle size'. The rod 'glow[ed] with great splendour', the glass 'became coated with a sooty deposit on its inside', and the rod 'became curved to the form of a bow, as if from softening'. B. S. Proctor's note in the same volume (read 27 Mar 1879) says that 'at our meeting in December, 1878, Mr. J. W. Swan exhibited an electric lamp ... which had broken down'. The report prints no day. The `time` is the middle of the December 1878 window; no source read gives a day (an earlier 18 Dec came from secondary summaries that were not kept). A rod that blackened its globe; no lasting lamp.		single documentn:lamp-1878-12-swan-rod-lamp-newcastle-chemical-society:0
1222 Oct 1879 (date only)22 Oct 1879: Edison's laboratory thread lamp burns 13 1/2 hours
Edison Papers, Doc. 1831 (Batchelor's notebook entry, '[Menlo Park,] Oct 22nd 1879 9 A.M.'): 'some very interesting experiments on straight carbons made from cotton thread'; 'a piece of 6 cord thread No 24 ... about 13 thousandths in thickness', carbonised in a closed chamber and put 'in vacuo'; 'it gave a light equal to about 1/2 candle 18 cells', resistance 113 ohms at starting, afterwards 140. 'No 9: On from 1.30 AM till 3 pm 13 1/2 hour and was then raised to 3 gas jets for 1 hour then cracked glass & busted.' The Papers' essay 'The Carbon-Filament Lamp' says the same. Clock times are the notebook's own; no time zone is given. The notebook image (N-79-07-31, p. 105) was not opened. 13 1/2 hours, not 40.		single documentn:lamp-1879-10-22-batchelor-cotton-thread-lamp:0, n:lamp-1879-10-22-batchelor-cotton-thread-lamp:1
1327 Jan 1880 (date only)27 Jan 1880: Edison's US patent 223,898 'Electric-Lamp' granted
US 223,898, 'Electric-Lamp', Thomas Alva Edison 'of Menlo Park, in the State of New Jersey', patented 27 Jan 1880. Claim 1 is a carbon filament of high resistance; claim 2 carbon filaments in a receiver made entirely of glass and exhausted of air, with the conductors passing through the glass; the specification names a mercury pump. The place is the inventor's address as printed (the scan's OCR of the address is poor; 'Menlo Park, New Jersey' is read from it), not where the patent issued. Filed 4 Nov 1879 (node lamp-1879-11-04-edison-files-patent-223898).		single officialn:lamp-1880-01-27-edison-patent-223898-granted:0
1404 Sep 1882 (date only)4 Sep 1882: Edison Electric Illuminating Company turns on light in the first Pearl Street district
New-York Tribune, 5 Sep 1882, p. 8: 'The company at 3 p.m. turned on the electric light in part of the first of the districts in which this kind of illumination is to be distributed from a common centre'; the 'central station ... is at ... Pearl-st., just below Fulton-st.'; the report is of 'yesterday' (Monday 4 Sep). Johnson is quoted as saying 'about one-third of the district' was lit. The company's own records were not read. Generation, wiring and metering were the commercial invention; the lamp was one part.		single median:lamp-1882-09-04-pearl-street-district-service-begins:0
15Jan 1885 (month only)Early 1885: Commissioner of Patents decides the Edison-Sawyer-Man interference for Sawyer and Man
40 F. 21: Edison applied in December 1879 (11 Dec) and Sawyer and Man on 9 January 1880; 'in September, 1880, an interference was declared between the two applications' over carbon made from paper; 'The case was not finally decided until the beginning of 1885.' Broadnax, the attorney who prepared the Sawyer-Man application, is quoted as speaking of 'the decision of the commissioner of patents of the interference, awarding priority of invention to Sawyer and Man' and puts the amendments that followed in February and March 1885. The Commissioner's decision itself was not read.		single officialn:lamp-1885-early-sawyer-man-win-interference:0
1605 Oct 1889 (date only)5 Oct 1889: Circuit court dismisses the Sawyer-Man patent suit (Consolidated Electric Light Co. v. McKeesport Light Co.)
40 F. 21 (C.C.W.D. Pa., 5 Oct 1889), Bradley J.: the Sawyer-Man patent (granted 12 May 1885; application filed 9 Jan 1880), apart from its third claim which was not in issue, is held to amount to 'the broad claim of the exclusive use, in incandescing lamps, of all carbons made of fibrous or textile materials' (headnote), and is held invalid; the court was 'not at all satisfied that Sawyer and Man ever made, and reduced to practical operation, any such invention', and found that the specification had been changed in 1885, after Edison's work was published, from the arched carbon to all fibrous carbons. 'The bill must be dismissed.'		single officialn:lamp-1889-10-05-bradley-holds-sawyer-man-claims-invalid:0
17Jul 1891 (month only)July 1891: Wallace J. holds Edison's claim 2 valid and infringed (47 F. 454)
47 F. 454 (C.C.S.D.N.Y., 1891), Wallace J.: Edison was 'the first to make a carbon of materials and by a process which was especially designed to impart high specific resistance to it', 'the first to make a carbon in the special form for the special purpose of imparting to it high total resistance', and 'the first to combine such a burner with the necessary adjuncts of lamp construction to prevent its disintegration and give it sufficiently long life'; 'By doing these things he made a lamp which was practically operative and successful'. The reporter prints '1891' only; 57 F. 616 says the judgment was obtained in July 1891.		reported officialn:lamp-1891-47f454-wallace-upholds-edison-lamp-patent:0, n:lamp-1891-47f454-wallace-upholds-edison-lamp-patent:1
1804 Oct 1892 (date only)4 Oct 1892: Court of Appeals (2d Cir.) affirms Wallace J. on Edison's second claim
52 F. 300 (C.C.A. 2d Cir., 4 Oct 1892), Lacombe J.: the second claim of patent 223,898 (carbon filament in an all-glass exhausted receiver with the conductors through the glass) is sustained and the decree affirmed. On the patent's term the court holds the patent in suit not affected by the loss of a Swedish patent (directly, or through Canadian patent No. 10,654 of 17 Nov 1879) and the Commissioner's attempted 'certificate of correction' limiting the term 'wholly void'. The decree is 'affirmed, with costs'.		single officialn:lamp-1892-10-04-appeals-court-affirms-edison-patent:0
1918 Feb 1893 (date only)18 Feb 1893: Colt J. (D. Mass.) grants Edison an injunction, finding Goebel's 1854 lamp 'extremely improbable'
54 F. 678, on a motion for a preliminary injunction, on about forty affidavits for Goebel and others against: 'It is extremely improbable that Henry Goebel constructed a practical incandescent lamp in 1854'; whether he made lamps 1, 2 and 3 'it is not necessary to determine. The weight of evidence on this motion is in the direction that he made these lamps, or lamps similar in general appearance ... But assuming they were made, they do not anticipate the invention of Edison. At most they were experimental toys'; of lamp No. 4: 'It is simply impossible, under the circumstances, to believe that a lamp so constructed could have been made by Goebel before 1872.' The court applied the rule that a new defence against a patent already upheld must be proved convincingly. Injunction granted. Preliminary ruling on affidavits.		single officialn:lamp-1893-02-18-colt-rules-on-goebel-defence-boston:0
2021 Apr 1893 (date only)21 Apr 1893: Hallett J. (E.D. Mo.) refuses an injunction on bond: 'a fair preponderance of testimony' for Goebel
56 F. 496, on a motion for a preliminary injunction: Goebel 'does not appear to be an adventurer or an impostor'; 'there is a fair preponderance of testimony in support of the Goebel claim'; 'a defense which puts the case in doubt is sufficient to defeat the application'. Judge Hallett says he does 'not feel compelled to accept the opinion of the court in' the Boston case. The injunction 'will therefore be refused, if the respondents shall give a bond in the sum of $20,000'. The ruling does not decide the Goebel claim finally. Preliminary ruling on affidavits; the other way.		single officialn:lamp-1893-04-21-hallett-refuses-injunction-goebel-defence-st-louis:0
2120 Jul 1893 (date only)20 Jul 1893: Seaman J. (E.D. Wis.) grants Edison an injunction, following Boston and disapproving St. Louis
57 F. 616, on a motion for a preliminary injunction against lamp makers at Oconto, Wis.: the headnote states the rule that a new defence against a patent upheld 'after protracted and expensive litigation' can be defeated only by 'convincing proof as will raise a presumption that it would have defeated the patent', every reasonable doubt being resolved against it; 54 F. 678 followed, 56 F. 496 'disapproved'. 'I cannot find that [the new affidavits] remove any of the doubts above noted.' Injunction granted. Preliminary ruling; the Seventh Circuit appeal below is the same case.		single officialn:lamp-1893-07-20-seaman-grants-injunction-goebel-defence-wisconsin:0
2201 May 1894 (date only)1 May 1894: Seventh Circuit affirms the Wisconsin injunction (the appeal in the same case)
61 F. 834 (7th Cir., 1 May 1894), on appeal from the preliminary injunction in 57 F. 616: the right of an owner of a patent upheld after protracted litigation to a preliminary injunction can be defeated only by a new defence proved convincingly; the court says that, 'without designing to suggest what result should be reached upon final hearing', the story of Goebel's early lamps 'is surrounded by such an atmosphere of improbability' that until sifted and sustained at final hearing it ought not to invade the patent holder's monopoly. This is the same case on appeal reviewing a discretionary preliminary ruling, not a fourth case.		single officialn:lamp-1894-05-01-seventh-circuit-affirms-wisconsin-goebel-ruling:0
2311 Nov 1895 (date only)11 Nov 1895: Supreme Court affirms the dismissal of the Sawyer-Man suit (The Incandescent Lamp Patent)
159 U.S. 465 (argued 29-30 Oct 1894, decided 11 Nov 1895; the scan's heading misprints the year as '1815'), Brown J.: 'we are all agreed that the claims of this patent, with the exception of the third [carbonised paper], are too indefinite to be the subject of a valid monopoly'; the question of priority 'becomes unnecessary'; 'the decree of the Circuit Court is Affirmed'. The Court also recounts Edison's search among 'about forty different kinds of bamboo' and says he 'despatched a man to Japan'. Holds the Sawyer-Man claims other than the third too indefinite; does not decide priority.		single officialn:lamp-1895-11-11-supreme-court-affirms-sawyer-man-decree:0
24Dec 1878 (month only)Dec 1878: Swan describes a carbon-rod lamp that blackened its globe (Newcastle Chemical Society)
Chemical News 39: at the Newcastle Chemical Society meeting, Mr. J. W. Swan in the chair (the meeting 'immediately preceding Christmas'), the chairman 'described an experiment he had recently performed on the production of light, by passing a current of electricity through a slender rod of carbon enclosed in an exhausted globe', current from a Siemens dynamo-electric machine 'of the second or 6000 candle size'. The rod 'glow[ed] with great splendour', the glass 'became coated with a sooty deposit on its inside', and the rod 'became curved to the form of a bow, as if from softening'. B. S. Proctor's note in the same volume (read 27 Mar 1879) says that 'at our meeting in December, 1878, Mr. J. W. Swan exhibited an electric lamp ... which had broken down'. The report prints no day. The `time` is the middle of the December 1878 window; no source read gives a day (an earlier 18 Dec came from secondary summaries that were not kept).		single documentn:lamp-1878-12-swan-rod-lamp-newcastle-chemical-society:0
25Apr 1879 (month only)About two years before 20 Oct 1880: Swan shows his 'little lamp' at the Lit and Phil (date unknown; 17 Jan or 3 Feb 1879 per secondary pages)
Swan, lecture of 20 Oct 1880 (Chemical News 42, pp. 227, 230): he began by referring to 'my last lecture on Electric Lighting, almost two years ago', and later said 'there are many here who will remember this little lamp, which I showed here two years ago in action', 'composed entirely of three substances, namely, glass, platinum, and carbon'. No 1879 report of the showing was found. The dates 3 February 1879 (Newcastle University; Linda Hall Library) and 17 January 1879 (Histelec) are from secondary pages that were seen only as search summaries. The `time` is the middle of the window; the 3 Feb and 17 Jan 1879 dates are from secondary pages seen only as search summaries (the alternative marker shows 17 Jan) and are not used as the date. Swan's own 1880 reference; date uncertain; no 1879 report found.
Other-source time: Histelec gives 17 Jan 1879; Newcastle University and the Linda Hall Library give 3 Feb (secondary, not read).		disputed witnessn:lamp-1879-02-03-swan-shows-lamp-lit-and-phil:0
2622 Oct 1879 (date only)22 Oct 1879: Edison's laboratory thread lamp burns 13 1/2 hours
Edison Papers, Doc. 1831 (Batchelor's notebook entry, '[Menlo Park,] Oct 22nd 1879 9 A.M.'): 'some very interesting experiments on straight carbons made from cotton thread'; 'a piece of 6 cord thread No 24 ... about 13 thousandths in thickness', carbonised in a closed chamber and put 'in vacuo'; 'it gave a light equal to about 1/2 candle 18 cells', resistance 113 ohms at starting, afterwards 140. 'No 9: On from 1.30 AM till 3 pm 13 1/2 hour and was then raised to 3 gas jets for 1 hour then cracked glass & busted.' The Papers' essay 'The Carbon-Filament Lamp' says the same. Clock times are the notebook's own; no time zone is given. The notebook image (N-79-07-31, p. 105) was not opened.		single documentn:lamp-1879-10-22-batchelor-cotton-thread-lamp:0, n:lamp-1879-10-22-batchelor-cotton-thread-lamp:1
2704 Nov 1879 (date only)4 Nov 1879: Edison applies for the patent that issues as 223,898
40 F. 21 (Bradley J.): Edison's patent 'applied for November 4, 1879, and issued January 27, 1880' (the opinion's number is printed 228,898 in the scan, a misprint). The patent, in the scan read, is signed 'this 1st day of November, A.D. 1879', and the Edison Papers' note says Edison 'executed' the application on 1 November. The application file was not read.		reported officialn:lamp-1879-11-04-edison-files-patent-223898:0, n:lamp-1879-11-04-edison-files-patent-223898:1
2816 Nov 1879 (date only)By 16 Nov 1879: Edison's laboratory has 'the first lamp that answers the purpose' (carbonised card)
Edison Papers essay 'The Carbon-Filament Lamp': 'By November 16, however, they had "the first lamp that answers the purpose we have wished. It is cheap much more so than we even hoped to have"', a horseshoe of charred paper cut from common card board, 'sealed in a glass bulb and the air exhausted'. The essay says 'By November 16'; the document it quotes was not opened.		single documentn:lamp-1879-11-16-first-lamp-that-answers-the-purpose:0
2921 Dec 1879 (date only)21 Dec 1879: NY Herald announces Edison's light and a New Year's Eve exhibition
New York Herald, 21 Dec 1879, p. 5, 'Edison's Light' (headings include 'A scrap of paper' and 'Success in a cotton thread'): 'The near approach of the first public exhibition of Edison's long looked for electric light, announced to take place on New Year's Eve at Menlo Park'. No byline is visible in the scan.		single median:lamp-1879-12-21-herald-announces-new-years-eve-exhibition:0
3031 Dec 1879 (date only)30-31 Dec 1879: crowds at Menlo Park see Edison's lights; Edison calls the announcement unauthorised
New York Herald, 31 Dec 1879 (dateline 'Menlo Park, N. J., Dec. 30'): Menlo Park 'thronged with visitors' all day; sixty lights; 'the Inventor has fixed no day for a general inspection by the public at large'. New-York Tribune, 1 Jan 1880: 'The unauthorized announcement' that the lights would be exhibited 'drew scores of persons to that place last evening' (31 Dec); Edison 'disclaimed any intention of giving any formal exhibition'; 'between fifty and sixty lights burning'; headline 'No public exhibition promised or given' (the headline's OCR is damaged and is read as that). Contested whether this was a public exhibition (lamp-menlo-park-dec-1879).		reported median:lamp-1879-12-31-menlo-park-visitors-no-formal-exhibition:0, n:lamp-1879-12-31-menlo-park-visitors-no-formal-exhibition:1
31Mar 1880 (month only)March 1880: Latimer begins work for Maxim at the U.S. Electric Lighting Company in Bridgeport
Queens Borough Public Library essay 'Inventing a Better Life: Latimer's Technical Career' (hosted by the Edison Papers): in Bridgeport, Connecticut, Latimer became 'an employee of Hiram Stevens Maxim, then chief engineer at the U.S. Electric Lighting Company'; he began there 'March, 1880'. The essay calls the company 'one of Edison's competitors' and says it moved to Brooklyn in 1880. A secondary account; Latimer's logbook and the company's records were not read. Secondary account (Queens Library essay hosted by the Edison Papers).		single analysisn:lamp-1880-03-latimer-joins-us-electric-lighting-bridgeport:0
321880 (year only)1880: Armstrong lights Cragside with Swan's incandescent lamps
IET Archives blog (2023), two passages: 'the arc lamps were replaced by Armstrong in 1880 with 45 incandescent lamps'; and Armstrong's letter to the editor of The Engineer of 17 January 1881 was written 'shortly after he utilised Joseph Swan's newly invented incandescent light bulbs'. That the 1880 lamps were Swan's is the blog's joining of the two passages. The letter itself was not read. The blog's 'first house in the world' is not used. Armstrong's 1881 letter not read.		single witnessn:lamp-1880-cragside-lit-with-swan-lamps:0
3320 Oct 1880 (date only)20 Oct 1880: Swan lectures on electric lighting and disputes Edison's priority on carbonised paper
Chemical News 42 (5 Nov 1880): J. W. Swan, lecture to the Newcastle-upon-Tyne Literary and Philosophical Society, 20 October 1880. He describes an experiment 'about twenty years ago' with a carbonised paper arch in a vacuum that 'became red-hot' and bent until it broke; calls it 'the very first instance in which carbonised paper was ever used in the construction of an incandescent electric lamp'; and says a Scribner's article's statement that Edison was first to use carbonised paper 'is incorrect'. It is Swan's own account, given while he disputed priority with Edison. Swan's own account while disputing priority.		single witnessn:lamp-1880-10-20-swan-lecture-lit-and-phil:0
3413 Sep 1881 (date only)13 Sep 1881: Nichols and Latimer, US patent 247,097 'Electric Lamp'
US 247,097, 'Electric Lamp', Joseph V. Nichols of Brooklyn and Lewis H. Latimer 'of the city, county, and State of New York', application filed 18 April 1881, dated 13 Sep 1881: 'Improvements in Incandescent Electric Lamps' in which the carbon strip is secured to the metallic wires, 'more especially ... the method of mounting the carbons or connecting them with the wires': wires pass through perforated ends of the carbon strip and are bent over into contact with it.		single officialn:lamp-1881-09-13-nichols-latimer-patent-247097:0
3528 Dec 1881 (date only)28 Dec 1881: the Savoy Theatre stage is lit with Swan lamps at a performance of Patience
The Times, Thursday 29 Dec 1881 (Gilbert and Sullivan Archive transcription): 'An interesting experiment was made at a performance of Patience yesterday afternoon, when the stage was for the first time lit up by the electric light, which has been used in the auditorium ever since the opening of the Savoy Theatre.' 'The Swan incandescent lamps were used.' The original page was not compared. The report is of an experiment at one performance, not of lamps in regular use. Via transcription; the original Times page was not compared.		single median:lamp-1881-12-28-savoy-stage-lit-by-swan-lamps:0
3617 Jan 1882 (date only)17 Jan 1882: Latimer, US patent 252,386 'Process of Manufacturing Carbons'
US 252,386, Lewis H. Latimer 'of New York, N. Y., assignor to the United States Electric Lighting Company, of same place'; application filed 19 February 1881, dated 17 January 1882; blanks are carbonised inside envelopes so that they do not stick, break or warp. The patent does not describe the company or its relation to Edison. Assigned to the United States Electric Lighting Company.		single officialn:lamp-1882-01-17-latimer-patent-252386:0
37Feb 1882 (month only)Early 1882: counsel Curtis first hears Goebel's story (lamps 'as early as about 1850')
54 F. 678, summarising Leonard E. Curtis's affidavit: he 'first heard of Henry Goebel in the early part of 1882', and Goebel told him he 'had made incandescent lamps like Edison's as early as about 1850', used 'for laboratory experiments' and not continued 'for more than a year or two after 1850'. Curtis inquired again in 1892 (Sawyer-Man injunction motion) and the defence was put forward in the 1893 suits.		single witnessn:lamp-1882-early-curtis-hears-goebel-story:0
38May 1882 (month only)May 1882: Dickerson and Dickerson tell Edison's lawyer Eaton of Goebel's claimed lamps
54 F. 678, summarising Sherburne B. Eaton's affidavit: 'in May, 1882, the law firm of Dickerson & Dickerson called his attention to the alleged inventions of Henry Goebel'; Goebel's representative was William C. Dreyer; the Edison company's executive committee 'decided that Goebel had nothing worth buying'.		single witnessn:lamp-1882-05-eaton-told-of-goebel-claim:0
391882 (year only)1882: Dreyer takes a paid option on Goebel's electric-lighting inventions
54 F. 678, summarising William G. Dreyer's affidavit: 'in 1882 he did procure from [Goebel] an option for three months of all his inventions relating to electric lighting' for $500, extended for three months for another $425. Goebel said he had made small incandescent lamps called the 'fiddle bow'; Dreyer 'made every effort to find one, but never succeeded'. No month is given.		single witnessn:lamp-1882-dreyer-option-on-goebel-inventions:0
4004 Sep 1882 (date only)4 Sep 1882: Edison Electric Illuminating Company turns on light in the first Pearl Street district
New-York Tribune, 5 Sep 1882, p. 8: 'The company at 3 p.m. turned on the electric light in part of the first of the districts in which this kind of illumination is to be distributed from a common centre'; the 'central station ... is at ... Pearl-st., just below Fulton-st.'; the report is of 'yesterday' (Monday 4 Sep). Johnson is quoted as saying 'about one-third of the district' was lit. The company's own records were not read.		single median:lamp-1882-09-04-pearl-street-district-service-begins:0
4124 Oct 1882 (date only)24 Oct 1882: Goebel's US patent 266,358 'Electric Incandescent Lamp' (a lamp-socket detail)
US 266,358, Henry Goebel 'of the city, county, and State of New York', assignor of one-half to John W. Kulenkamp; application filed 23 January 1882, dated 24 October 1882: an electric vacuum-lamp in which the carbon conductor is secured in flattened, spirally coiled ends of the lead-in wires and cemented. Both claims are for the sockets.		single officialn:lamp-1882-10-24-goebel-patent-266358:0
4228 Nov 1882 (date only)28 Nov 1882: Goebel's son offers the Edison company his father's inventions for $20,000
54 F. 678, summarising Sherburne B. Eaton's affidavit: 'On November 28, 1882, Henry Goebel, Jr., called upon him ... and made another offer to sell the inventions and good will of his father, naming the price of $20,000'; on 12 December 1882 he 'was informed that the company did not wish to buy'. This is not the earliest trace of the Goebel claim: Curtis (early 1882), the Dickersons' approach (May 1882) and Dreyer's option (1882) are earlier.		single witnessn:lamp-1882-11-28-goebel-offer-to-edison-company:0
43Oct 1883 (month only)Oct 1883: Edison and Swan United Electric Light Company formed by merger
Edison Papers company page: 'established in October 1883 as the result of a merger between the Edison Electric Light Company, Ltd. and the Swan United Electric Light Company, Ltd.' No day is given.		single officialn:lamp-1883-10-edison-and-swan-united-formed:0
44Jan 1885 (month only)Early 1885: Commissioner of Patents decides the Edison-Sawyer-Man interference for Sawyer and Man
40 F. 21: Edison applied in December 1879 (11 Dec) and Sawyer and Man on 9 January 1880; 'in September, 1880, an interference was declared between the two applications' over carbon made from paper; 'The case was not finally decided until the beginning of 1885.' Broadnax, the attorney who prepared the Sawyer-Man application, is quoted as speaking of 'the decision of the commissioner of patents of the interference, awarding priority of invention to Sawyer and Man' and puts the amendments that followed in February and March 1885. The Commissioner's decision itself was not read.		single officialn:lamp-1885-early-sawyer-man-win-interference:0

People and bodies involved

Sources

Generated from timeline.yaml by build/tools/render_timeline.py. This page records what is reported and where reports differ. It is not a finding about what happened.