This spectacular clock, a tour de force of horological and scientific complexity, was made for Louis-François de Bourbon, Prince de Conti, a cousin of Louis XV. It was celebrated as a technological marvel not only in the 18th Century but also in the Empire period, when it was admired by the renowned horloger Antide Janvier.
THE PRINCE DE CONTI
Born in Paris on 13 August 1717, Conti was the son of Louis Armand de Bourbon, Prince de Conti and Louise Elizabeth de Condé. At the age of fourteen he married Louise Diane d'Orléans, daughter of Philippe duc d'Orléans and Françoise Marie de Bourbon, on 22 January 1732 at Versailles. She died giving birth to their only son. Following military campaigns in Bohemia, Italy, Germany and the Netherlands he was considered as a candidate to the throne of Poland. Although he did not secure this he remained a confidante of Louis XV until a falling out with the royal mistress Madame de Pompadour. Conti was then in opposition to the government and exiled from the court but secured a priviledged retirement in his role as Grand Prior of the Knights of the Order of Malta, residing at the Palais du Temple in Le Marais. His enclave at the Temple became a centre for social life and his art collecting habits were lavish. A particular interest in astronomy and horology saw him commission not only the present clock, but also a magnificent planisphere by Fortier, the case attributed to Jean-Pierre Latz (now in the J. Paul Getty Museum). His fame also rests on the Romanée vineyard he acquired in 1760 to which he added his last name: Romanée-Conti which remains one of the most prized wines in the world.
Following his death on 2 August 1776 at the age of 58, his son inherited considerable debts which forced the auction of 1777. In this legendary sale, conducted by Remy, the clock realised the highest price, more than double that of the Fortier planisphere. The catalogue describes the clock:
‘2020. A clock surmounted by a moving sphere, executed after the tables of MM. Cassini and de La Lande. Diverse moving spheres have previously been seen and justly approved by the greatest connoisseurs. The particular merit of this example is that it contains within a much smaller space all the same objects and the same details, and produces, particularly as concerns the Moon, effects which are truer and more exact. There can be no greater precision than that which is found in this piece, whose mechanism has commanded the attention of all the savants who have examined it. The artistry which prevails in all the particulars of its execution, the delicacy and finish of its workmanship, have equally won the approbation of lovers of art.’ (‘2020. Une pendule surmontée d’une sphère mouvante, exécutée d’après les tables de MM. Cassini & de La Lande. On a vu jusqu’ici diverses sphères mouvantes justement approuvées des plus habiles Connoisseurs. Le mérite particulier de celle-ci est de renfermer dans un espace beaucoup plus resserré tous les mêmes objets, les mêmes détails, & de produire sur-tout par rapport à la lune, des effets plus vrais & plus exacts. La précision ne peut être portée plus loin qu’elle se trouve l’être dans cette pièce dont le méchanisme a fixé l’attention des Savants qui l’ont examinée. Le goût qui regne dans toutes les parties de son exécution, la délicatesse & le fini de la main d’oeuvre, ont pareillement réuni les suffrages des Amateurs de l’art.’).
Following the French Revolution the clock was with the famed clockmaker Antide Janvier (1751-1835), probably as a seized item and entrusted to him for adjustment and restoration. In his Etrennes chronométriques pour l’an 11 (Paris, 1810) concerning the methods of calculating wheels, Janvier mentions the present mechanical sphere in laudatory terms: ‘The numbers employed in the planetary clock made by Mabille for the Prince de Conti, were calculated with greater care than those of Passemant, by Baffert, clockmaker, employing the method of Camus (Cours de mathématique, volume IV, p. 399)’ (‘Les nombres employés dans la pendule planétaire, exécutée par Mabille pour le prince de Conti, furent calculés avec plus de soins que ceux de Passemant, par Baffert, horloger, en employant la méthode de Camus (Cours de mathématique, tome IV, p. 399)’).
The clock was then in the collection of Baron Gustave Samuel de Rothschild and remained with the family until the late 20th century.
LA SPHÈRE MOUVANTE
The sphère mouvante or orrery is a mechanical device for portraying the relative motions of the sun, moon and Earth and sometimes, as in this instance, the planets. Among the first known examples was that of circa 1710 by George Graham (1673-1751). A subsequent machine made in 1716 by John Rowley came into the possession of Charles, 4th Earl of Orrery and subsequently the instrument was named (in English) in honour of its owner.
The orbital periods and planetary movements of the Conti clock are taken from tables devised by the astronomers de La Lande and J. Cassini, (Eléments d'Astronomie: tables astronomiques du Soleil, de la Lune, des planètes, des étoiles fixes, et des satellites de Jupiter et de Saturne, Paris, 1740) and wheelwork calculated by Charles-Etienne-Louis Camus. Camus, in his 1749 work Cours de mathématique, details the teeth of clockwork gears and pinions necessary for obtaining a wheel with an annual average revolution of 365 days and 49 minutes, and a synodical revolution of the Moon of 29 days, 12 hours, 44 minutes, 3 seconds, and 12 tierce.
During the 18th Century a number of mechanical planetaria were devised and constructed, often by clockmakers, such as Jacques-Thomas Castel’s clock of 1763 (Anonymous sale, Christie’s, London, 7 July 2011, lot 44) and Conti’s planisphere clock by Alexandre Fortier of circa 1745-49 (Wilson, op. cit.).
Greatly admired in its day as the ultimate creation of the clockmaker's art, the sphère mouvante was also a manifestation of the spirit of the Enlightenment. It must have given the 18th-century savant enormous pleasure to create a clockwork mechanism that could accurately mimic the motions of the Heavens, and in doing so bring to visible fruition the 16th and 17th-century revolution in astronomy brought about by Copernicus, Kepler, Galileo and Newton.
Mabille (1734–1801) was apprenticed to Michel-Victor Gaultier (1753) and before 1773 was an ouvrier libre in Saint-Germain-des-Prés. He was on the jury entrusted with developing the new time system of the Revolution (1793). Initially he made only movements and worked for Couppy, Lecomte and Verieux, the marchand-mercier Antoine Magnien and the gilder M.F. Noel, subsequently selling pieces under his own name in the final years of the ancien régime and also used clock cases by Antoine Foullet and François Vion. After the Revolution he supplied movements to Pierre-Philippe Thomire.
Baffert (active in Paris during the third quarter of the 18th century, d. after 1779), an ouvrier libre, resided with his wife Marie-Jeanne de La Haye in the Quinze-Vingts quartier. In addition to this mechanical sphere for the Prince de Conti, his name also appears on the month-going floor-standing orrery clock made by Jacques-Thomas Castel (1710-72) later owned by Baron Mayer Amschel de Rothschild (1818-74) and subsequently the Earls of Rosebery, at Mentmore Towers (Anonymous sale; Christie’s, London, 7 July 2011, lot 44). He used clock cases by Fremont and Jourdan. He was declared insolvent and went bankrupt on 25 October 1773, at which time he owed 730 livres to Mabille.