Achille Brocot / Jean-Baptiste Delettrez à Paris, Movement No. 743, Height 430 mm, circa 1880
An exquisite, almost as new, skeletonized, astronomical multi-barrel year-duration clock with perpetual calender, equation of time and half hour / hour self strike
Case: brass, gilt, the curved frame mounted on a wooden base, decorated with gold-colured Vernis Martin and flower heads, the front plate profusely engraved with foliate scrolls. Dial: enamel dial with radial Roman numerals, recessed centre with visible Brocot escapement, signed, blued Breguet hands; a painted enamel calendar dial below with equation of time and a polychrome enamelled night sky with a moon aperture, three subsidiary dials for indications of the weekday, date and month with signs of the zodiac, blued hands. Movm.: circular brass clock movement, stamped with a star and numbered, sixteen tandem spring barrels (four double barrels to each side) geared to the going and strike train barrels above, 2 hammers, 1 bell, compensation pendulum, additional circular brass movement for calendar indications.
Louis "Achille" Brocot (1817–1878)
Achille Brocot was a French clockmaker and amateur mathematician. He is known for his discovery (independently of and contemporaneously with German number theorist Moritz Stern) of the Stern–Brocot tree, a mathematical structure useful in approximating real numbers by rational numbers; this sort of approximation is an important part of the design of gear ratios for clocks. He also made many other horological innovations including refinement of his father Louis-Gabriel's Brocot escapement and the development of clocks with perpetual calendar mechanisms.
Source: http://en.wikipedia.org/wiki/Achille_Brocot, as of 02/20/2014.
机蕊 非常好, 走動正常
机蕊 非常好, 走動正常