Little is known of Bachelard. He is recorded in Rue Montorgueil in Year IX (1800) and working in Paris until 1817. Perhaps surprisingly, Tardy records him as a maker of 'montres a masse', leading to the conclusion that the present regulateur was either his masterpiece or acquired from another workshop as it is a decidedly superior piece of horology. The dial is of the finest quality and bears comparison with the very best of the period, such as those by Coteau, Dubuisson and Merlet, although it is signed neither to front nor reverse. See for comparison the zodiac dial on a table regulator by Cronier signed and dated (1800) by Dubuisson which was sold Christie's London, The Vitale Collection of Highly Important European Clocks, 26 November 1996, lot 279; and another zodiac dial on a regulateur de parquet by Godon in the Spanish Royal Collection also with a dial by Dubuisson (see Derek Roberts, Precision Pendulum Clocks: France, Germany, America and Recent Advancements, Atglen, 2004, p. 86, figs. 30-4).