A rare French decimal system round hanging pendulum wall clock, employing a system proposed by the French mining engineer J. de Rey-Pailhade called the “centiday.” The enameled clock dial is enclosed within hinged glazed door. The pendulum driven works are in the round case. Under Pailhade’s scheme, instead of dividing the day into 24 hours, timekeeping would follow the metric system, dividing the day into 100 parts (roughly equivalent to 15-minute increments). The white enameled dial features an outer ring of numerals printed in black in increments of 100. The middle ring of blue numerals aligns that decimal time with the conventional 24-hour day system, subdivided into 10-minute increments, the conventional way of marking time that the decimal system was intended to supplant. The inner ring of red numerals is also in decimal time, but divided into 24 increments to facilitate conversion from the conventional system into decimal time. The gilt-brass pointer is decorated with an engraved sun face. The central part of the dial is decorated with a 6-pointed star enclosing a circumpolar world map, a significant inclusion, because Pailhade advocated for the decimal system as a means of simplifying time zone conversions between locations in France and its colonies around the world.
In France, there were two movements to convert to decimal time keeping (also referred to as metric time). Decimal time was introduced during the French Revolution in the decree of October 5, 1793: “The day, from midnight to midnight, is divided into ten parts, each part into ten others, so on until the smallest measurable portion of duration. … The hundredth part of the hour is called decimal minute; the hundredth part of the minute is called decimal second.” Although clocks and watches were produced with faces showing both standard time with numbers 1–24 and decimal time with numbers 1–10, decimal time never caught on; it was not officially used until September 1794 and mandatory use was suspended in April 1795.
In the 1890s, there was a second attempt to convert to decimalization of time in France, when the Commission de Décimalisation du Temps was created by the Bureau des Longitudes, with the eminent mathematician Henri Poincaré as secretary. This clock was produced during this second wave of interest in decimalization. In April 1897, the Toulouse Chamber of Commerce adopted a resolution in favor of the application of the decimal system to the division of time and of the circle as proposed by Pailhade. Meanwhile, Poincaré’s commission proposed a compromise of retaining the 24-hour day, but dividing each hour into 100 decimal minutes, and each minute into 100 seconds. The plan did not gain acceptance and was abandoned in 1900. Pailhade, however, continued to advocate for the decimal system into the first decades of the 20th century.
L. Leroy & Cie. was a French firm manufacturing watches, chronometers and fine clocks under that name from around 1888, as successor to Ancienne Maison Le Roy et fils, a clockmaking firm with origins in the late 18th century. The firm was owned by Louis Leroy (1860-1935), who accumulated many prizes and honors during his lifetime, winning the Besançon Chronometric Cup several times, and becoming an Officer of the Legion of Honor in 1930. In 1914, he went into partnership with his brother Léon, who continued the business after Louis’s death in 1935. After Léon’s death in 1961, his sons took over the firm and continued to develop innovative timepieces using the latest technology.
Gannett, Henry “Book Notices.” Journal of the American Geographical Society of New York, Volume 30. American Geographical Society of New York, 1898. p. 81. Online at Google Books. 16 December 2008. http://books.google.com/books?id=9zTOAAAAMAAJ (17 May 2010).
de Rey-Pailhade, J. Le Temps Décimal: Avantages et Procédés Pratiques. Paris: Gauthier-Villars & Fils, 1894. Online at Google Books. http://books.google.com/books?id=ICMNAQAAIAAJ (2 February 2010).
“Leroy.” Dictionnaire des Horlogers de Tardy. Online at Worldtempus, Official Web Site of Famous Brands. 2010. http://www.worldtempus.com/en/encyclopedia/index-encyclopedia/horlogers-celebres/leroy (2 February 2010).
“Metric Time.” Wikipedia. 29 January 2010. http://en.wikipedia.org/wiki/Metric_time (1 February 2010).