Provenance: The property of an important American family since the 1920 's. Formerly in the Dollfns Collection. History: This clock is recorded in Breguet 's archives for the first time under No. 125, in the same firm ' s ledger than the famous Moultes pehjpetuelles, under the date of 7 November 1791, together with 17 other pieces. This register is the earliest one still in existence and it is more than likely that these pieces were in fact produced at an early date. According to the archives of Breguet: No. 125 The first one, was sold to Mr. Veaujour in January 1792 against a watch of a value of 240 Francs. Bought back from Wenham, it was restored and sold under No. 3243, to Mr. Ic Comte de Message on 4 February 1829 for 450 Francs. No. 96 Another one, was sold to Mr. Anisson du Perron on 30 May 1792 for 1440 Francs. No. 2397 A third one, commissioned] to the Maison de Russie, was sold by Moreau to Prince Galitzin on I May 1810 for 1800 Francs, but since it is indicated in the archives, that this clock was made from elements of No. 306 Etablissement Etrangers, where are recorded pieces which were not produced in the Breguet's workshop, it is certainly of a different type than the two others. Therefore, the only other pendttle branlante that has survived is now kept in the Mused National des Techniques at the Conservatoire National des Arts et Metiers in Paris, where it was delivered soon after it was seized during the Revolution, from the home of the Duc d ' Orleans, in 1790, together with his metronome clock (see Jean-Dominique Augarde: Les Ouvriers du 'Iintps, Antiquorum Editions - Geneve 1996, p. 291). Note: Based on principles demonstrated by Newton 's laws, involving kinetic energy, inertia and harmonic motion, the Penchdes hranlantes as devised by Breguet, are not linked in any way to the bracket and seem to oscillate mysteriously. The oscillation of the pendulum is maintained by a combination of forces, as explained above in the description. There is a small pendulum inside the bob, linked to the escapement. The clock is able to run in the stationery position, since the small internal pendulum will oscillate of its own accord. However, the bimetallic compensation is incorporated into the long rod which in its turn provides the line tuning of the internal escapement and its counterweight. That the minuscule movement of the internal "pendulum" can drive such a mass most have appeared as something as miracle at the time. As opposed to such "mystery oscillating clocks ", a lot of balancelles, as they were called at the time, were produced in Morez (French Jura) during all the 19th century. They were mainly sold to the jewellers and watchmakers in order to be exposed in the shop windows as an attr action and to give time both from inside the shop and from the street. These clocks can in no stay be compared with the Pendules hranlantes as made by Breguet, since their oscillation was provided by the impulse, given by the escapement, using a conventional "crutch" working against a fixed point, usually a rigid extension of the bracket. However the principal of the original Breguet's pendules branlantes, was heavily exploited at the end of the 19th century for the novelty clocks balanced on the trunks of elephants etc., and si milar " mystery " clocks relying on the impulse of a tiny mass to drive an extended pendulum. Pierre Simon, Marquis de Laplace, celebrated mathematician and astronomer, was born on March 28, 1749. Son of a poor farmer of Beaumonten-Auge, near Trouville, be studied at Caen and, after teaching mathematics, went to Paris as professor in the Royal Military School. He became famous for his mastery of the whole range of mathematical science and its application to practical astronomy. He was chosen an Associate of the Academy of Sciences in 1773 and Member in 1785. His correct generalisation that our planetary system is stable, bestowed upon astronomy the ,Three Laws of Laplace». He explained the <