A good large French 19th century Repeat, alarm, striking carriage clock, c.1870, in heavy gilded brass case with recessed square corner pillars and concave moulded borders on bracket feet. Silvered dial mask with cutout face, Arabic numerals and subsidiary alarm dial. Signed D CHAILLIAUT BORDEAUX. Silver platform with bi-metallic balance and lever escapement. (stops and starts).
- Gilding - Gilding is a method of ornamentation whereby a thin sheet of gold metal is applied to items made of wood, leather, ceramics, glass and silver for decorative purposes.
For furniture including mirrors, the sheet of gold is usually applied over a coating of gesso. Gesso is a mixture of plaster of Paris and gypsum mixed with water and then applied to the carved wooden frames of mirrors and picture frames as a base for applying the gold leaf. After numerous coats of gesso have been applied, allowed to dry and then sanded a coat of "bole", a usually red coloured mixture of clay and glue is brushed on and allowed to dry, after which the gold leaf is applied. Over time parts of the gilding will rub off so the base colour can be seen. In water gilding, this was generally a blue colour, while in oil gilding, the under layer was often yellow. In Victorian times, gilders frequently used red as a pigment beneath the gold leaf.
Metal was often gilded by a process known as fire gilding. Gold mixed with mercury was applied and heated, causing the mercury to evaporate, the long-term effect of which was to kill or disable the craftsman or woman from mercury poisoning. The pursuit of beauty has claimed many victims, not the least of which were the artists who made those pieces so highly sought after today.
- Lever Escapement - A lever escapement is a type of escapement mechanism used in mechanical clocks and watches to regulate the timekeeping of the movement. It was invented by British clockmaker Thomas Mudge in the 18th century and is now widely used in modern mechanical timepieces.
The lever escapement consists of three main parts: the escape wheel, the pallet fork, and the lever. The escape wheel is a wheel with teeth that is driven by the clock or watch's main spring or weight. The pallet fork is a two-pronged component that is positioned so that it can engage with the teeth of the escape wheel, and the lever is a small, L-shaped component that is attached to the pallet fork.
When the escape wheel turns, one of its teeth pushes against one of the pallet fork's prongs, causing the fork to pivot. As the pallet fork pivots, it releases the tooth and engages with the next tooth on the opposite side of the escape wheel. At the same time, the lever, which is connected to the pallet fork, rocks back and forth, allowing the escape wheel to turn at a regulated rate.
The lever escapement is prized for its accuracy and reliability and is commonly used in high-end mechanical watches. It allows for precise timekeeping by ensuring that the movement of the watch or clock is regulated and consistent, and its compact size makes it an ideal choice for use in small, portable timepieces.
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