The Origin of the Lunar Craters: An Eighteenth-Century View

Robert Hooke , Micrographia (London, 1665), 243–6.

See for example, Encyclopédie, ou Dictionnaire raisonné des sciences, des arts, et des métiers (Paris, 1751–65), article “Lune” (by d'Alembert); or Encyclopaedia Britannica (1st ed., Edinburgh, 1771), section on the Moon in the article “Astronomy”; or, finally, Ephraim Chambers's Cyclopaedia, or an Universal Dictionary of Arts and Sciences (revised ed., London, 1779–86), article “Moon”.

I have searched in vain in a large number of treatises on astronomy and/or natural philosophy spanning the entire eighteenth century, for a recognition that the origin of the lunar surface features was even a subject worthy of discussion. None of the earlier encyclopedias I have consulted raises the question, nor do any of the small number of journal articles listed under the relevant subject-headings in Houzeau and Lancaster's bibliography and dated earlier than those to be discussed in this paper. Finally, neither Delambre's Histoire de l'astronomie au dix-huitième siècle (Paris, 1827), nor that other great nineteenth-century history of astronomy, Robert Grant's History of physical astronomy (London, 1852), mentions our problem.

Archibald Geikie Sir , The founders of geology (2nd ed., London, 1905), chaps. 4, 5.

Guettard J. E. , “Mémoire sur quelques montagnes de la France qui ont été des volcans”, Histoire de l'Académie royale des Sciences pour l'année MDCCLII (Paris, 1756), Mémoires, 27–59.

Demarest N. , “Mémoire sur l'origine et la nature du Basalte …”, Histoire … pour l'année MDCCLXXI (Paris, 1774), Mémoires, 705–75.

Naples , 1776. A Supplement was published in 1779. Hamilton sent each of his early reports to the Royal Society of London, and they were published initially in the Philosophical transactions of the Society (lvii (1767), 192–200; lviii (1768), 1–14; lix (1769), 18–22; lx (1770), 1–19; lxi (1771), 1–47). All but the fourth of these were included in the Campi Phlegraei, along with a series of introductory remarks drawn up in the form of an additional letter.

De Soulavie Giraud , editor of Œuvres complettes de M. le Chevalier Hamilton (Paris, 1781), justified his publishing what amounted to a cheaper octavo version of the Campi Phlegraei on the grounds that the demand for copies of the latter had been such that they had come to command a price far beyond the means of “humble students of Nature” ( Sleep Mark C. W. , “Sir William Hamilton (1730–1803): His work and influence in geology”, Annals of science , xxv (1969), 319–38).

Guettard , loc. cit. 44.

Hamilton , Philosophical transactions , lix (1769), 21.

Mayer Euler , 23 February 1755; Euler Mayer , 27 May 1755: In Kopelevich Yu. Kh. , “Perepiska Leonarda Eilera i Tobiasa Maiera”, Istoriko-astronomicheskie issledovaniya , v (1959), pp. 422 and 425 respectively.

Aepinus became involved in extra-scientific official duties within a few years of his arrival in St Petersburg in 1757. From the sub-title to his paper on the lunar craters, we learn that at the period with which we are concerned here, he held the rank of “würklicher Staats-Rath” in Catherine's College of Foreign Affairs.

Aepinus , “Ueber den Bau der Mondfläche, und den vulcanischen Ursprung ihrer Ungleichheiten”, Schriften der Berlinischen Gesellschaft naturforschender Freunde , ii (1781), 1–40. I have drawn my account of the circumstances in which Aepinus composed his paper from his own introduction to it.

Ibid. , 12–13. On Nasmyth and Carpenter, see their The Moon considered as a planet, a world, and a satellite (London, 1874, and numerous subsequent editions), and also Von Wolff F. , Der Vulkanismus (Stuttgart, 1914), i, chap. 15, “Der lunare and kosmische Vulkanismus”.

Aepinus , op. cit. , 24–5: “Wer mit diesen Begriffen von dem Bau und der Form vulcanischer Hervorbringungen, den Mond untersuchet, wird mit Verwunderung seine ganze Fläche mit dergleichen bedeckt finden, und daselbst alle Arten derselben, vulcanische Becken mit und ohne Molfetten sowohl, als würkliche Vulcane, mit offenem und geschlossenem Schlunde, mit und ohne Laven, mit und ohne Molfetten u.s.f. in der größten Menge gewahr werden.”.

Ibid. , 26–27.

Ibid. 28.

Ibid. , 29–30.

Ibid. 32: “Es kostet der Natur nicht wie dem Menschen mehr Mühe, im Größten als in Kleinen zu arbeiten.”.

Ibid. , 35–8. Evidently, Aepinus did not feel that his denial of the existence of a lunar atmosphere led to any physical difficulties when placed in conjunction with his earlier conclusion that the maria were genuine seas. Vapour pressure is not an eighteenth-century concept!.

Ibid. 40: “Der Schluß von der Aehnlichkeit der Würkungen auf die Aehnlichkeit der Ursachen, ist in der Naturlehre von großem Gewicht, allein ohne den gehörigen Einschränkungen ist er unzuversläßig.”.

Aepinus , “Lettre … sur les Volcans de la Lune”, Nova Acta Academiae Scientiarum Imperialis Petropolitanae , ii (1784; publ. 1788), Hist., 50–2.

Throughout 1782, Hamilton's personal affairs were such that his failure to act on Aepinus's behalf can readily be forgiven (assuming he received the manuscript in the first place). Apart from the fact that Hamilton was kept exceedingly busy by his diplomatic duties, his first wife, Catherine, of whom he was very fond, was very ill, and in fact was obviously dying for months before the end finally came in August of that year ( Fothergill B. , Sir William Hamilton, envoy extraordinary (London, 1969)).

Aepinus also arranged to have a Russian translation of his paper published in parts in succeeding numbers of the short-lived St Petersburg journal Akademicheskiya Izvestiya, but unfortunately the journal ceased publication with only the first part of his paper in print. He is reported to have then arranged for 100 copies of the translation to be published separately at his own expense ( Svodnyl katalog russkol knigi grazhdanskol pechati XVIII veka 1725–1800 [ Moscow , 1963–66], iv, 118), but whether these ever actually saw the light of day is doubtful.

Aepinus , “Lettre …”, 51: “Après les déscriptions détaillées, & les représentations exactes en figures, que plusieurs sçavans avoient données depuis une dixaine d'années, de la configuration des inégalités terrestres produites par les éruptions du feu souterrain, l'opinion de l'origine volcanique des inégalités de la Lune étoit un fruit parfaitement mur, qui ne pouvoit pas manquer de tomber dans les mains de celui qui s'avisoit par hazard, de secouer l'arbre quelque legérement que ce fut.”.

[ Lichtenberg ], “Ein Paar Neuigkeiten vom Monde”, pp. 25–30 in the Göttinger Taschen-Calender for 1779 (publ. August 1778). A few years later, Lichtenberg re-published his paper along with some additional explanatory remarks ( Göttingisches Magazin der Wissenschaften und Litteratur , ii (1781), 26–33); he confessed as he did so that his action had been prompted by news he had received from Russia, from the astronomer Lexell A. J. , to the effect that “Hr. Prof. Aepin zu Petersburg einen ähnlichen Gedanken gehabt, und in einer bis jezt noch ungedruckten Abhandlung bereits ausgeführt habe.”.

Ferber Presumably J. J. , “Beobachtungen über die Schwefelgrube zu Pozzuolo …”, in Arduino G. , Sammlung einiger mineralogisch-chymisch-metallurgisch und oryktographischer Abhandlungen (Dresden, 1778); and Björnståhl J. J. , Briefe auf Reisen durch Frankreich, Italien, u.s.w. ( Rostock , 1777–84).

Beccaria , “Intorno ad alcuna particella, che riluca nel disco delia Luna interamente oscurata”, Opuscoli scelti sulle scienze e sulle arti (Milan), iii (1780), 166–73. A précis of Beccaria's article was published in the following year in Observations sur la physique, sur l'histoire naturelle et sur les arts (Rozier's Journal) , xvii (1781), 447–9; our quotations are drawn from this latter source.

Ulloa's report was published in a number of the scientific journals of the time. I have used the version in Philosophical transactions , lxix (1779), 105–19.

Beccaria had long been possessed of a fierce ambition for scientific glory. By 1780, his life was evidently drawing to a close, with ill-health interrupting his work more and more frequently (he in fact survived only until May 1781), and yet his ambition remained unfulfilled. In these circumstances, he may well have yielded to the temptation of exaggerating his claims a little. (On Beccaria , see Antonio Pace , Benjamin Franklin and Italy (Philadelphia, 1958), chap. 3).

It was chiefly to welcome the news of Herschel's observation that Aepinus composed his second paper on lunar vulcanism. In addition, besides noting (as we have seen) the views of Lichtenberg and Beccaria, he drew attention in this paper to the pioneering work of Hooke (with which he had in the meantime become acquainted), and suggested that the newly-observed “volcano” should be named in the latter's honour.

Lubbock Constance A. , The Herschel chronicle (Cambridge, 1933), 170, quotes from the entry in Fanny Burney's Diary for 30 December 1786, reporting a visit to Herschel: “The moon … has already afforded him two volcanoes”.

Herschel , “An account of three volcanoes in the Moon”, Philosophical transactions , lxxvii (1787), 229–32.

Middlchurst Barbara M. , Chronological catalog of reported lunar events (Washington, 1968).