LATE 18TH CENTURY

‘Inclined plane’ clocks appear to have been invented during the first half of the seventeenth century by one of the Isaac Habrechts, (either Isaac I (1544-1620) or Isaac III (1611-1686)). The clocks were certainly popular in France during the second half of the eighteenth century. In the 1770’s the Parisian clockmaker Bazile Legros supplied such clocks to Marie-Antoinette and to the Prince de Condé. Later Gaspard II Comte de Servière (1676-1745) of Lyon continued the theme and devised numerous variations which his grandson Nicolas Grollier de Servière later published in ‘Recueil D’ouvrages Curieux de Mathematique et de Mecanique’.
The principle of these clocks is the use of a counterweight within the drum case, linked to the center wheel of the movement and its train of wheels which thereby stops it rolling down the slope.