“For the Good of Astronomy”: The Manufacture,Sale,and Distant Use of William Herschel's Telescopes

RAS MS Herschel W.7/8.

RAS MS Herschel W.5/12.1, expt 264. Entry 264 reads: “His Majesty requiring me to make some 10 feet telescopes, I cast several mirrors for them in a small furnace erected in my house, they were 9 inches in diameter, or about 8,8 of polished surface when finished. I ground and polished five of them at different times.” The entry is undated, but as entry 266 is dated 10 March 1784, Herschel must have started on the project in late 1783 or early 1784. A second entry in April 1785 suggests that Herschel was still at work on the telescopes.

For an account of the circumstances leading to Herschel's pension, see Simon Schaffer , “Uranus and the establishment of Herschel's astronomy”, Journal for the history of astronomy , xii (1981), 11–26. The King took his time paying the bill. Herschel wrote to Mr Gieswell on 26 Feb. 1791: “I beg you will be so obliging as to mention to the King, when you find a convenient opportunity, that the 5th ten-feet telescope which I have made for his Majesty has been ready a great while, and that I fear it is not safe in the place where I am obliged to keep it, so that I wish for his Majesty's orders where to deliver it. At the same time I beg the favor of you to tell me whether I shall send the bill for these five telescopes to you to give to the King, or whether you know where it would please his Majesty that I should send it. The King knows very well that astronomers and experimental philosophers are always poor, and, as the liberal patron of Arts and Sciences, I make no doubt, will not suffer them to be in want.” Letter 656, in vol. i of The later correspondence of George III , ed. by Aspinall A. (Cambridge, 1962).

Especially Bennett James A. , “‘On the power of penetrating into space’: The telescopes of William Herschel”, Journal for the history of astronomy , vii (1976), 75–108.

A major contribution is however Andreas Maurer's “A compendium of all known William Herschel telescopes”, Journal of the Antique Telescope Society , no. 14 (1998), 4–15. Maurer set out to document the “fate and whereabouts” of Herschel telescopes that have survived, wholly or in part, or for which substantial documentation exists. In what follows we cast our net more widely, attempting to include all those instruments mentioned (however briefly) in the records.

James Sime , William Herschel and his work (New York, 1900), 122.

Ibid. , 104.

Agnes Clerk , The Herschels and modern astronomy (New York, 1895), 33. So too in his 1919 biography, Macpherson wrote that “the work of making telescopes for other observers, though lucrative, was in many respects a waste of time. Herschel had long contemplated the construction of a very large telescope, but this was impossible so long as his spare time was given to the manufacture of smaller instruments, the great majority of which passed into the possession of royal or aristocratic dabblers in astronomy and were practically mere ornaments”. Hector MacPherson , Herschel (London, 1919), 31.

Angus Armitage , William Herschel (London, 1962), 27.

On Caroline Herschel , see Michael Hoskin , The Herschel partnership, as viewed by Caroline (Cambridge, 2003; hereafter Partnership ), and Caroline Herschel's autobiographies , ed. by Michael Hoskin (Cambridge, 2003; hereafter Autobiographies ).

Autobiographies , 78–79.

King Henry C. , The history of the telescope (High Wycombe, 1955; reprint edn, New York, 1979), 127. Richard Lerner similarly concluded that Herschel “made about fifty telescopes in the period” between 1782 and 1785 ( Astronomy through the telescope (New York, 1981), 60). Sidgwick J. B. , though less precise about the number of telescopes produced, believed that much of the work was done at Datchet. “The rising pressure of astronomical work at Datchet was balanced by no corresponding relaxation in the workshop…. [Herschel] began to receive requests for his telescopes in ever-increasing numbers, and the manufacture of reflectors for private sale … soon developed into a thriving concern” ( William Herschel: Explorer of the heavens (London, 1953), 102).

Autobiographies, 79. On the funding of the 40ft, see Michael Hoskin , “Herschel's 40ft reflector: Funding and functions”, Journal for the history of astronomy , xxxiv (2003), 1–32.

By way of comparison, Herschel made 531 entries in the polishing logs between 2 Dec. 1790 and 16 Dec. 1793.

Between 1782 and 1785 Herschel made a mirror for Schroeter's 4ft telescope and a mirror for Thomas Parsons (entry 251). He repolished a Gregorian mirror for Bryant John B. (entry 252), a 9-inch mirror for Alexander Aubert (entry 266), and the mirror of a 7ft reflector that he had made for his ally William Watson (entry 257).

See Michael Hoskin , “Alexander Herschel: The forgotten partner”, Journal for the history of astronomy , xxxv (2004), in press.

Published in Astronomisches Jahrbuch for 1788, 161–4.

For a description of James Short's business, see Harriet Wynter and Anthony Turner, Scientific instruments (New York, 1975), 199.

Dreyer J. L. E. , The scientific papers of Sir William Herschel (2 vols, London, 1912; hereafter Dreyer), i, p. li transcribes Herschel's own list of instruments and the prices he had charged, which total £14, 743.

Harry Ransom Humanities Research Center, University of Texas at Austin, Herschel Family Papers, manuscript M1114 (n.d). The list is reprinted in Dreyer , pp. –li. At the bottom of his list, Herschel wrote: “the above list of persons for whom telescopes were made, is partly put down from memory and cannot be supposed to contain a complete account of them.” Indeed, Herschel forget to note the sale of telescopes or mirrors to Tiberius Cavallo (1787), Inspektor Kohler (1789), Mr Henry of Dublin (1790), Schmidt J. J. (1791), Baron Hahn (1794), Mr Larkin (1797), Mr Carrington (1799), William Hodgson (1799), Baron Hahn (1800), Bertheau M. (1800), Kritoff Gen. (1805), and Mr Hausemann (1811).

See Tables 1 and 2 for a complete list of all of the telescopes mentioned in Herschel's correspondence and polishing logs. Two of the undated instruments were definitely made before 1790: A 7ft for the Duke of Richmond which he asked Herschel to repair in 1790, and a 7ft for Mr Trudaine. Trudaine's telescope is mentioned in Seymour Chapin L. , “‘In a mirror brightly’: French attempts to build reflecting telescopes using platinum”, Journal for the history of astronomy , iii (1972), 87–104, p. 89.

RAS MS Herschel W.1/1 [entries in chronological order], Herschel to Mayer, 8 Oct. 1782.

Autobiographies , 73.

John Tracy Spaight, “Alexander Herschel as telescope maker”, Journal for the history of astronomy , xxxiv (2003), 95–96; Hoskin , “Alexander Herschel” (ref. 16).

Autobiographies , 55.

Autobiographies , 78.

Herschel William Alexander , 10 March 1785, RAS MS Herschel W.1/9.3. A journeyman was a workman who had completed his apprenticeship.

In a letter of 25 Aug. 1801, Herschel wrote “let William when he goes to Windsor call on Taylor the cabinet maker, to inquire if the tube and two stands are finished”, letter to Caroline, RAS MS Herschel W. 1/8.

RAS MS Herschel W.1/1, Herschel to Cavallo, 17 Dec. 1787.

The Royal Archives, Windsor Castle , RA GEO/6650: “Received from his Majesty by the hands of Mr. Gieswell Dec. 12, 1785 the sum of £200 and on Feb 18, 1786 the sum of £300, in all five hundred pounds, advanced on account, for an instrument now making for his majesty's encouragement, Feb. 18, 1786.” Other payments were made in July and Nov. 1787, Feb., April and July 1788, and June 1789.

For Mary's increasing affluence see Partnership , 92, 95–96.

“Beucoup peuroient que votre telescope etoit sujet a des illusions optiques”, Jean-Dominique de Cassini Herschel , 15 Feb. 1785, RAS Herschel MS W.1/13.C.6.

William Herschel , “On the parallax of the fixed stars”, Philosophical transactions , lxxvii (1782), 82–111, and “Catalogue of double stars”, ibid. , 112–52.

Watson William Herschel , 25 Dec. 1781, RAS MS Herschel W.1/13.W.13.

“Even Nairne doubted of your power”, Watson Herschel , 18 Dec. 1781, RAS MS Herschel W.1/13.W.12.

Ramsden objected that at a power of 6450, a celestial object would take “less than a second in passing thro' the center of your field of view”. Watson Herschel , 11 Jan. 1782, RAS MS Herschel W.1/13.W.14. Herschel responded in his letter to Watson of 13 Jan., RAS MS Herschel W.1/1.

“Aubert could not help being suspicious of some mistake”, Watson Herschel , 18 Dec. 1781, RAS MS Herschel W.1/13.W.12. Herschel sent Aubert sky charts with double stars marked in red ink, and begged him to verify that the stars were indeed double, Herschel to Aubert, 9 Jan. 1782, RAS MS Herschel W.1/1, see Lubbock C. A. , The Herschel chronicle (Cambridge, 1933), 102–3.

“Dr Maskelyne told me yesterday after the Society was over, that tho' he did not in the least doubt your veracity, he could not help thinking that you was mistaken as to your high powers”, Watson Herschel , 11 Jan. 1782, RAS MS Herschel W.1/13.W.14.

The German astronomer Johann Schroeter later expressed another concern, confiding to Herschel that “I can not comprehend how such an instrument [a 7ft reflector], with a magnification of 1000 times, can still give sufficient light, to see your double stars”, Schroeter Herschel , 31 July 1783, RAS MS Herschel W.1/13.S.14.

RAS MS Herschel W.1/13.W.13, Watson Herschel , 25 Dec. 1781.

RAS MS Herschel W.1/13.W.15, Watson Herschel , 4 Jan. 1782. The difficulties Herschel encountered are recounted in Simon Schaffer , “Herschel in Bedlam: Natural history and stellar astronomy”, The British journal for the history of science , xiii (1980), 211–39.

RAS MS Herschel W.1/1, Herschel to Aubert, 9 Jan. 1782.

RAS MS Herschel W.1/1, Herschel to Hornsby, 1 Feb. 1782.

British Library ADD MS 22,897, Cavallo Lind , 27 Dec. 1782.

RAS MS Herschel W.1/13.A.8, Aubert to Herschel, 22 Jan. 1782.

RAS MS Herschel W.1/13.M.16, Maskelyne Herschel , 5 Feb. 1782. Even when he acquired a 7ft reflector from Herschel in 1791, he still experienced difficulties: “I have made use of the late fine weather to try what I could see with the 7 feet reflector, which you furnished the observatory with. I have seen Σ Bootes very well with it, but can make nothing of η Corona Borealis, with the power … which I recon to be 350. With the next which I take to be 500 I can see nothing but a confused blaze…. I have also looked at Saturn with this telescope, which it shews very well, but have never seen more than two satellites with it.” Maskelyne to Herschel, 15 Sept. 1791, RAS MS Herschel W.1/13.M.49.

On faulting instruments or assistants rather than valued colleagues, see Steve Shapin , A social history of truth (Chicago, 1994), chap. 5, “Epistemological decorum: The practical management of factual testimony”.

RAS MS Herschel W.1/1, Herschel Bode , 18 May 1784. “Je crois que votre Dollond vous donnera une tres par faite avec un aggrandisment de 300 pour les etoiles doubles; mais il y en a qui en demandent plus & que vous ne verres jamais avec un tel instrument.” In other words, a good telescope was one that could resolve Herschel's double stars! See also RAS MS Herschel W.1/13.S.14, Schroeter Herschel , 31 July 1783.

RAS MS Herschel W.1/1, Herschel to Mayer, 8 Oct. 1782.

William Herschel , “Catalogue of double stars”, Philosophical transactions , lxxv (1785), 40–126.

RAS MS Herschel W.1/1, Herschel to Lalande, 23 May 1783.

King , History of the telescope (ref. 12), 160: “Astronomers wished to see Herschel's William Sir double stars for themselves and they began to assess the performance of their telescopes by the ease with which they resolved these objects.” King notes this put pressure on Dollond and others.

Which could lead to “the Experimenter's Regress” problem described by Harry Collins , Changing order: Replication and induction in scientific practice , 2nd edn (Chicago, 1991). Many French astronomers had trouble verifying Herschel's double star observations. On Mechain's difficulties, see Schaffer , “Uranus and the establishment of Herschel's astronomy” (ref. 3), 21.

Jean-Dominique de Cassini Herschel , 15 Feb. 1785, RAS MS Herschel W.1/13.C.6.

According to a pamphlet in a cardboard box stored in 1998 on a shelf next to reference desk in the library of the History and Philosophy of Science Department at Cambridge University.

William Herschel , “Catalogue of one thousand new nebulae and clusters of stars”, Philosophical transactions , lxxvi (1786), 457–99, p. 467.

“Ici [Palermo] je vais etablier un Observatoire qui peut-etre contribuera aux progress de l'astronomie. Ce serai donc un domage, que je fus restraint a ne voir le Ciel, qu'a vu les telescopes ordinaires.” Piazzi Herschel , 5 Aug. 1790, RAS MS Herschel W.1/13.P.16.

RAS MS Herschel W.1/13.0.4, Oriani to Herschel, 30 April 1792.

Clerke Agnes C. , The Herschels and modern astronomy (London, 1895), 34.

National Library of Wales , Wygfair manuscript 12418D, Shuckburgh Lloyd , 5 Oct. 1778. John Lloyd's instruments and observatory are described in Bibliotheca Lywydiana , “A Catalogue of the Entire Library … and Philosophical Apparatus, the Late Property of John Lloyd, esq.”.

See Sotheby & Co. Catalogues of sales: A guide to the microfilm collection 1734–1850 , Reel 19, 21 July 1806.

The reflector is mentioned ibid. , Reel 36, 20 Aug. 1823.

In “Conceptual problems with the use of the terms amateur and professional for the 18th century”, a paper given at the meeting of the History of Science Society in 1999, I argued that the terms ‘amateur’ and ‘professional’ were not mutually defining until the nineteenth century, that many of the nuances that would later accrue to these terms do not map onto eighteenth-century experience, and finally that the terms do much to obscure the wide diffusion of expertise between those who worked at Greenwich (for example), and those who worked in private observatories.

On Von Hahn's observatory, see Astronomisches Jahrbuch (hereafter AJB ), 1797, 240–4. On the 12-inch mirror, he noted: “Ich habe die Politur dieses Spiegels aussert schön gefinden; sein Oberfläche gleicher einem reinen Wasser ohne Faber”.

Scottish National Archives, Papers of Count de Brühl , GD 157/3385/2, Letter from Comte de Knuht to de Brühl , 2 Jan. 1790: “Depuis votre depart de Dresden nous avons recue un ministre de Prusse. Mon le Comte de Gesler! qui est grand connoisseur! et amateur! de l'astronomie et d'autre sciences. Je regrets beaucoup qu'avant mon depart de Dresden son Telescope de Herschel grand 7 pied! n'estoit pas encore arrivé.”.

See Allgemeine Deutsche Biographie , 444, and Poggendorff J. C. , Biog.-litt. Handwörterbuch zur Geschichte der exacten Wissenschaften , i, 1290.

Herschel's Kitchener noted William desire to have his observations verified: “Dr. Herschel has expressed a wish, (that as they are some of the finest, most minute, and most delicate objects of vision he ever beheld,) to hear his observations have been verified by other persons, and offers the following caution, as to the adjustment of the focus of our telescopes, and advises those who wish to examine the closest of these curious double stars …” ( A companion to the telescope , 2nd edn (London, 1811), 10).

RAS MS Herschel W.1/13.E.4, Edwards Herschel , 27 August 1794, and H.22, Hodgson Herschel , 2 August 1805. William Hodgson's reflector is listed in his estate sale: Sotheby & Co. Catalogues (ref. 61), Reel 37, 28 Feb. 1824.

RAS MS Herschel W.1/13.G.11, Gimingham to Herschel, 9 Nov. 1796.

Andrew Ure , The philosophy of manufactures (London, 1835).

RAS MS Herschel W.1/13.U.1, Ure Herschel , 12 April 1812.

“Die Briefe Friedrich v. Hahns an William Herschel , 1792–1800”, Archenhold-Sternwarte Berlin-Treptow, Sonderdruck no. 36, ed. by Dietmar Fürst Jürgen Hamel (Berlin-Treptow, 1990), Letter 6, Hahn Herschel , 10 Oct. 1798. “Die Liebe zur astronomie beginnt sich in Deutschland auszubreiten. Dazu haben vor allem Ihre großen Entdeckungen beigtragen.”.

See Georg Christoph Lichtenberg: Briefwechsel , ed. by Joost U. Schöne A. , iii (Munich, 1983), Letter 2000, Schroeter Lichtenberg , 8 January 1792. For references to Schroeter's observations with the 7ft Herschel reflector cited in the Astronomisches Jahrbuch (AJB) , see AJB , 1787, 253–4; AJB , 1789, 150–4; AJB , 1790, 194–205; AJB , 1791, 216–20; AJB , 1791, 201–3; AJB , 1792, 150; AJB , 1792, 176–90; AJB , 1793, 202; AJB , 1794, 124–6; AJB , 1795, 206–19; AJB , 1796, 158–60; AJB , 1799, 153–4; AJB , 1800, 166–75; AJB , 1801, 193–201.

“… selbst die Krater hatten keinen Glanz”, in “Ueber den Mondfleck Aristarchus”, AJB , 1791, 201–3.

“Ueber die von verschiedenen Astronomen in der dunkeln Seite des Mondes bemerkten Lichtpunkte”, AJB , 1792, 112–27.

Lichtenberg: Briefwechsel , iii (ref. 73), Letter 1638, Lichtenberg to Sömmerring Thomas Samuel , 9 Nov. 1788.

“Beobachtungen von Fixsternenbedeckungen, zu Göttingen angestellte”, AJB , 1797, 223–4.

Olbers W. , Letter of 7 August 1824, Astronomische Nachrichten , no. 63 (1824), cols. 241–2, cited by Andreas Maurer in a preliminary and unpublished version of his “Compendium” (ref. 5).

AJB , 1792, 111; AJB , 1794, 170; AJB , 1795, 248–50; AJB, 1799, 131–5.

AJB , 1802, 211–16.

AJB , 1790, 227–32; AJB , 1793, 249; AJB , 1794, 241–6; AJB , 1795, 226–32; AJB , 1797, 155–8; AJB , 1802, 204–10; AJB , 1803, 106–7; AJB , 1804, 195–7; AJB , 1805, 97; and AJB , 1806, 215–19.

Using the 20ft telescope. See AJB , 1803, 106–7, and Robert Burnham , Burnham's celestial handbook (New York, 1978), ii, 1164.

AJB , 1790, 147; AJB , 1794, 202–13; AJB , 1796, 176–7.

AJB , 1802, 211–16.

RAS MS Herschel W.1/13.K.7–29.

Schofield Robert E. , The Lunar Society of Birmingham: A social history of provincial science & industry in 18th century England (Oxford, 1963).

Schofield commented, “The Soho Works early became a place to be visited, one of the wonders of ‘modern’ England”, op. cit. , 27.

“Copies of diaries kept by WH on various tours, 1791–1817”, RAS MS Herschel W.7/15, p. 5.

Richard Sorrenson , “George Graham, visible technician”, The British journal for the history of science , xxxii (1999), 203–23. Sorrenson contends that the ‘invisible technicians’ of the seventeenth-century Royal Society gave way to the increasingly visible and respected technicians of the eighteenth century.

On the Enlightenement interest in ‘improvement’, see Lorraine Daston , “Afterward: The ethos of Enlightenment”, in William Clark Jan Golinski Schaffer Simon (eds), The sciences in enlightened Europe (Chicago, 1999), 495–504, p. 496. See also Larry Stewart , “A meaning for machines: Modernity, utility, and the eighteenth-century British public”, Journal of modern history , lxx (1998), 259–94.

Schofield describes an exchange of letters between Small and Watt. On 31 January 1770, for example, Watt wrote to Small: “I propose when you and I meet to spend some of our leisure time on trying some experiments &c on glass for Dollonds.” In a letter of 19 October 1771, Small wrote to Watt: “I have been by the way endeavoring to cheapen & improve telescopes, but I have not due leisure.” Schofield , op. cit. (ref. 86), 105–6.

Smeaton's interest in astronomy and the engineering drawings he prepared for these observatories will be the subject of a later article. For a guide to the engineering drawings, see A catalogue of the civil and mechanical engineering designs 1741–1792 of John Smeaton, F.R.S., preserved in the library of the Royal Society (London, 1950). The plans for the observatories are in vol. iv, folios 21–27.

Huddart was elected F.R.S in 1791. He sent observations on eclipses of Jupiter's moons observed at Bombay, 25 March 1780 to Maskelyne (RGO4/187 misc. corresp).

John Gascoigne , Science in the service of Empire: Joseph Banks, the British state, and the uses of science in the Age of Revolution (Cambridge, 1998).

The picture of Herschel as abstract theorist, untouched by worldly concerns, obscures his ties with business and engineering circles — ties that grew stronger in the next generation of British astronomers. On the commercially-oriented men who founded the Royal Astronomical Society, whom Ashworth labelled “business astronomers”, see Ashworth William J. , “The calculating eye: Baily, Herschel, Babbage, and the business of astronomy”, The British journal for the history of science , xxvii (1994), 409–41.

RAS MS Herschel W.1/1, Herschel Lalande , 23 May 1783.

Lubbock , The Herschel chronicle (ref. 37), 116.

Bennett , op. cit. (ref. 4), 89.

RAS MS Herschel W.5/14.1, f.18. Quoted in Bennett , op. cit. (ref. 4), 91.

RAS MS Herschel W.1/1, Herschel to Shairp at St Petersburgh, 9 March 1794.