Faujas-De-Saint-Fond Visits the Herschels at Datchet

Barthélemy Faujas-De-St-Fond , Voyage en Angleterre, en Écosse et aux îles Hébrides: Ayant pour objet les sciences, les arts, l'histoire naturelle et les moeurs avec la description mineralogique du pays de Newcastle des montagnes du Derbyshire, des environs d'Edinburgh, de Glasgow, de Perth, de S. Andrews, du duche d'Inverary et de les grotte de Fingal (2 vols, Paris, 1797).

Barthélemy Faujas-De-St-Fond , Travels in England, Scotland, and the Hebrides; undertaken for the purpose of examining the state of the arts, the sciences, natural history and manners, in Great Britain (2 vols, London, 1799). The translator is not known.

The date of Faujas's visit to Datchet is not stated directly and requires some inference. Although it is commonly acknowledged that the year of Faujas's tour was 1784, he does not actually mention the year anywhere in the narrative. However, shortly before he visited the Herschels Faujas attended a meeting of the Royal Society of London, at which the Elector Palatine of Bavaria was admitted as a member; see Voyage (ref. 1), i, 60–63; Travels (ref. 2), i, 52–54. According to The record of the Royal Society of London for the Promotion of Natural Knowledge (4th edn, London, 1940), 431, this election occurred on 12 August 1784. Faujas subsequently visited the country house of Joseph Banks Sir “on the 15^th of August” (one of the few dates Faujas explicitly provides). After dining with Banks, “at seven in the evening … I took leave of Sir Joseph , and set off to meet William Herschel , who expected me…. The house in which Mr. Herschel makes his observations … is about twenty miles distant from the house of Joseph Banks Sir . … I arrived at Mr. Herschel's about ten o'clock” ( Voyage (ref. 1), i, 69–71, 74; Travels (ref. 2), i, 59–60, 63). So we can say with some certainty that Faujas arrived at Datchet on 15 August 1784 and observed into the morning of 16 August. Unfortunately the Herschels' Visitors Book, currently on loan to the William Herschel Museum at Bath, was not yet in full use at this early date.

Faujas , Voyage (ref. 1), i, 74–76; Travels (ref. 2), i, 63–65. I have utilized the 1799 translation throughout, since it is quite faithful, and have made only a few minor changes.

Bennett J. A. , “On the power of penetrating into space': The telescopes of William Herschel”, Journal for the history of astronomy , vii (1976), 75–108, p. 87. The device was introduced by William on 7 August, a week before Faujas's visit (RAS Herschel MS W.7/8, 37).

Faujas , Voyage (ref. 1), i, 81; Travels (ref. 2), i, 69. The manuscript book that Faujas refers to is almost certainly the zone catalogue of stars that Caroline prepared from John Flamsteed's British Catalogue of stars, and which was one of Caroline's first major contributions to William's observing program. The zone catalogue is discussed by Michael Hoskin , “Caroline Herschel: Assistant astronomer or astronomical assistant?”, History of science , xl (2002), 425–44, pp. 432–3, and more fully in Michael Hoskin , The Herschel partnership, as viewed by Caroline (Cambridge, 2003), 70, 72, and idem (ed.), Caroline Herschel's autobiographies (Cambridge, 2003), 84–85.

Hoskin , “Caroline Herschel” (ref. 6), 432–3.

This recalls the slightly later account of de Magellan Jean Hyacinth (Joã o Jacinto de Magalhã es), who visited Datchet on 6 January 1785 and published a brief account in the Astronomisches Jahrbuch für das Jahr 1788 (Berlin, 1785), 162–4. Magellan explicitly recalled seeing Flamsteed's atlas at Caroline's desk. He further claimed that she wrote down the declination and right ascension for each observation; if in fact he was misinterpreting her notations of polar distance and sidereal time, this would be further confirmation of Faujas's opinion that Caroline was recording star positions directly. Magellan's account was first brought to light and translated by Edward S. Holden in his Sir William Herschel: His life and works (London, 1881), 78–79.

RAS Herschel MSS W.7/8, 37.

Bennett , op. cit. (ref. 5), 87.

Ibid. , 86.

Faujas , Voyage (ref. 1), i, 77; Travels (ref. 2), i, 66.

Faujas , Voyage (ref. 1), i, 81; Travels (ref. 2), i, 69. The relevant passage is quoted in full above.