18 novembre 1752 (1) : Clairaut n'est pas à l'Académie.
Sa présence n'est pas reportée sur les procès-verbaux (PV 1752, p. 543). C'est la première des 33 séances (non compte tenu de l'assemblée publique du 15 novembre, séance pour laquelle les PV ne relèvent pas les présents) que Clairaut manque à cause de son premier voyage en Angleterre. Il part après avoir écrit sa lettre à Grischow du 1 octobre (cf. 1 octobre 1752 (1)) et revient probablement entre le 24 et 28 mars 1753 (cf. 24 mars 1753 (1), 28 mars 1753 (1)). Clairaut avait indiqué à Euler qu'il allait se mettre à l'anglais (cf. 28 avril 1751 (2), 17 mai 1765 (2)). Il a lu les pièces du prix avant de partir (cf. 23 novembre 1752 (2)), sauf peut-être celle de Pereire (cf. 18 novembre 1752 (3)). Rapporteur habituel avec Nicole de Bouguer, il sera remplacé par d'Arcy pour l'examen du Nouveau traité de navigation dont il est rendu compte le 25 novembre (Bouguer 53, p. xxiii). L'Angleterre est alors sous le règne de Georges II depuis 1727 et le sera jusqu'à sa mort en 1760 (Worsley 06, p. 89). Elle venait d'adopter, en septembre 1752, le calendrier grégorien. Le voyage de Clairaut est peut être motivé par le prix des longitudes (cf. 18 novembre 1752 (2)). Clairaut assiste à sa première séance à la Royal Society le 23 novembre (cf. 23 novembre 1752 (1)). Il participe à l'élection de Macclesfield qui remplace Folkes à la présidence de la Royal Society (cf. 30 novembre 1752 (2)). Il est traité en héros (cf. [c. novembre 1752]), même si certains excès (cf. 15 décembre 1752 (1)) doivent être corrigés (cf. 30 décembre 1752 (1)). Il présente à la Royal Society un exemplaire de (Courtivron 52) le 7 décembre (cf. 7 décembre 1752 (1)). C'est peut-être aussi d'Angleterre qu'il écrit à Voltaire sur Courtivron (cf. 1752 (1), 2 janvier [1753]). Il s'adresse au secrétaire de la Royal Society (cf. 7 février 1753 (1)) avant de présenter C. 41 bis en séance (cf. 15 février 1753 (1)). Un exemplaire de C. 39 envoyé par l'Académie de Saint-Pétersbourg est présenté à la Royal Society le 15 mars 1753 (cf. 15 mars 1753 (1)). Il parle à Chesterfield (cf. 1 janvier 1753 (1)), fait la connaissance de Arthur Onslow, le Speaker de la Chambre des communes (cf. 6 avril 1753 (2)), et de Samuel Richardson, avec lequel il restera en relation suivie (cf. Prévost). Ce dernier prépare alors (Richardson 53-54) dont Clairaut lit les premières feuilles, non sans remarquer dans la maison « a pretty female » (cf. 7 octobre 1753 (1)). Il revient peut-être avec des cartes géographiques pour Delisle dans ses bagages (cf. 30 novembre 1752 (1)). Il est de retour à l'Académie le 28 mars 1753 (cf. 28 mars 1753 (1)) et remercie le président de la Royal Society (cf. 6 avril 1753 (1)). Clairaut fera un second voyage en Angleterre (cf. 30 janvier 1754 (1)). Clairaut indique à Jacquier qu'il a fait un voyage en Angleterre seul (cf. 19 février 175[8]). En recommandant Boscovich, il se souviendra de l'accueil qu'il a connu à Londres (cf. [16 mai 1760]). Selon Ferner, Clairaut aime les anglais pour leur sincérité (cf. 17 décembre 1760 (2)) et pense que Londres a 100 000 habitants de plus que Paris (cf. 8 janvier 1761 (1)). La Condamine croit savoir que Clairaut n'a pas assez montré d'estime pour les géomètres anglais (cf. 17 juillet 1765 (1)). C'est probablement lors de ce premier voyage que Clairaut rencontre Thomas Simpson : The Eight (and last) part [pp. 120-179] comprehends the resolution of some general, and very interesting problems, in mechanics and physical Astronomy […] The greater part of what is here delivered on this subject [lunar orbit], was drown up in the year 1750, agreeably to what is intimated at the conclusion of my Doctrine of Fluxion, where the general equations are also given. The famous objection, about that time made to Sir Isaac Newton's general law of gravitation, by that eminent mathematician M. Clairaut, of the royal Academy of science at Paris, was a motive sufficient to induce me (among many others) to endeavour to discover, whether the motion of the moon's apogee, on which that objection had its whole weight and foundation, could not be truly accounted for, without supposing a change in the received law of gravitation, from the inverse ratio of the squares of the distances. The success was answerable to my hopes, and such as induced me to look farther into other parts of the theory of the moon's motion, than I first intended : but, before I had completed my design, I received the honnor of a visit from M. Clairaut (just then arrived in England) of whom I learned that he had a little before printed a piece on that subject ; a copy of I afterwards received, as a present at his hands. [...] But I cannot omit to observe here, in justice to M. Clairaut, that, tho' he indeed fell into a mistake, by to hastily inserring a defect in the received law of attraction, from the insufficiency of the known methods for determining the effect of that attraction, in the motion of the moon's apogee, yet he was himself, the first who discovered the true source, of that mistake, and who placed the matter into a proper light. [...] Since M. Clairaut's piece first made its appearance, the most mathematicians, in differents place in Europe, have turned their thoughts that way (Simpson 57, non paginé). Autre version : According to what Mr Simpson had intimated at the conclusion of his Doctrine of Fluxions, the greatest part of this arduous undertaking was drawn up in the year 1750. About that time M. Clairaut, a very eminent mathematician of the French Academy, had started an objection against Sir Isaac Newton's general law of gravitation. This was a motive to induce Mr Simpson (among some others) to endeavour to discover whether the motion of the moon's apogee, on which that objection had its whole weight and foundation, could not be truly accounted for, without suppofing a change in the received law of gravitation, from the inverse ratio of the squares of the distances. The success answered his hopes, and induced him to look farther into other parts of the theory of the moon's motion, than he had at first intended : but before he had completed his design, M. Clairaut arrived in England, and made M[onsieu]r Simpson a visit; from whom he learnt, that he had a little before printed a piece on that subject, a copy of which M[onsieu]r Simpson afterwards received as a prefent, and found in it the fame things demonftrated, to which he himfelf had directed his enquiry, befides several others (Simpson 92, xvi-xvii) (Douglas Rogers, CP, 19 mars 2009). Clairaut a aussi vu Keralio en Angleterre (cf. 9 janvier 1763 (1)), probablement William Watson (cf. 1 février 1755 (1)), et il est ami avec John Bevis, Stanley, James Macdonald ou Lord Morton (cf. 10 avril [1765]).
Abréviations
C. 39 : Clairaut (Alexis-Claude), Théorie de la Lune déduite du seul principe de l'attraction réciproquement proportionelle (sic) aux quarrés des distances... Pièce qui a remporté le prix de l'Académie impériale des sciences de Saint Pétersbourg en 1750..., Saint-Pétersbourg, 1752, in-4°, 92 p [Télécharger] [6 décembre 1750 (1)] [Sans date (1)] [(7 novembre) 27 octobre 1737 (1)] [Plus].
C. 41 bis : Clairaut (Alexis-Claude), « A translation and explanation of some articles of a book intitled Théorie de la figure de la Terre ; by Mons. Clairaut, of the Royal Academy of Sciences at Paris, and F. R. S. », Philosophical Transactions, vol. 48, part. I, 1753, London, 1754, pp. 73-85 [Télécharger] [15 février 1753 (1)] [(7 novembre) 27 octobre 1737 (1)] [Plus].
CP : Communication personnelle.
PV : Procès-Verbaux, Archives de l'Académie des sciences, Paris.
Courtivron (Gaspard Le Compasseur de Créquy-Montfort, marquis de), Traité d'optique, Paris, 1752 [24 juillet 1739 (1)] [Plus].
Richardson (Samuel), The History of Sir Charles Grandison in a series of letters, London, 1753-1754 [6 avril 1753 (2)] [Plus].
Simpson (Thomas), Miscellaneous Tracts, J. Nourse, London, 1757.
Simpson (Thomas), Hutton (Charles), Select Exercises for Young Proficients in the Mathematicks, New ed., London, 1792 [Télécharger].
Courcelle (Olivier), « 18 novembre 1752 (1) : Clairaut n'est pas à l'Académie », Chronologie de la vie de Clairaut (1713-1765) [En ligne], http://www.clairaut.com/n18novembre1752po1pf.html [Notice publiée le 1 décembre 2010].
The Eight (and last) part [pp. 120-179] comprehends the resolution of some general, and very interesting problems, in mechanics and physical Astronomy […]
The greater part of what is here delivered on this subject [lunar orbit], was drown up in the year 1750, agreeably to what is intimated at the conclusion of my Doctrine of Fluxion, where the general equations are also given. The famous objection, about that time made to Sir Isaac Newton's general law of gravitation, by that eminent mathematician M. Clairaut, of the royal Academy of science at Paris, was a motive sufficient to induce me (among many others) to endeavour to discover, whether the motion of the moon's apogee, on which that objection had its whole weight and foundation, could not be truly accounted for, without supposing a change in the received law of gravitation, from the inverse ratio of the squares of the distances. The success was answerable to my hopes, and such as induced me to look farther into other parts of the theory of the moon's motion, than I first intended : but, before I had completed my design, I received the honnor of a visit from M. Clairaut (just then arrived in England) of whom I learned that he had a little before printed a piece on that subject ; a copy of I afterwards received, as a present at his hands. [...] But I cannot omit to observe here, in justice to M. Clairaut, that, tho' he indeed fell into a mistake, by to hastily inserring a defect in the received law of attraction, from the insufficiency of the known methods for determining the effect of that attraction, in the motion of the moon's apogee, yet he was himself, the first who discovered the true source, of that mistake, and who placed the matter into a proper light. [...] Since M. Clairaut's piece first made its appearance, the most mathematicians, in differents place in Europe, have turned their thoughts that way (Simpson 57, non paginé). Autre version :
According to what Mr Simpson had intimated at the conclusion of his Doctrine of Fluxions, the greatest part of this arduous undertaking was drawn up in the year 1750. About that time M. Clairaut, a very eminent mathematician of the French Academy, had started an objection against Sir Isaac Newton's general law of gravitation. This was a motive to induce Mr Simpson (among some others) to endeavour to discover whether the motion of the moon's apogee, on which that objection had its whole weight and foundation, could not be truly accounted for, without suppofing a change in the received law of gravitation, from the inverse ratio of the squares of the distances. The success answered his hopes, and induced him to look farther into other parts of the theory of the moon's motion, than he had at first intended : but before he had completed his design, M. Clairaut arrived in England, and made M[onsieu]r Simpson a visit; from whom he learnt, that he had a little before printed a piece on that subject, a copy of which M[onsieu]r Simpson afterwards received as a prefent, and found in it the fame things demonftrated, to which he himfelf had directed his enquiry, befides several others (Simpson 92, xvi-xvii) (Douglas Rogers, CP, 19 mars 2009). Clairaut a aussi vu Keralio en Angleterre (cf. 9 janvier 1763 (1)), probablement William Watson (cf. 1 février 1755 (1)), et il est ami avec John Bevis, Stanley, James Macdonald ou Lord Morton (cf. 10 avril [1765]).