Antique French Green Onyx Clock with Pendulum
You must be a subscriber, and be logged in to view price and dealer details.
Subscribe Now to view actual auction price for this item
When you subscribe, you have the option of setting the currency in which to display prices to $Au, $US, $NZ or Stg.
- Onyx - Onyx is a form of agate, used from antiquity and popular again in the 1920s and 30s. European onyx is generally green, but can be many other colours, and can contain bands of black and/or white.
This multicoloured stone is widely used for table tops, lamp bases and in jewellery. Some types of onyx are also used for cameos of which the upper white layer is cut away to reveal the colour beneath. - Pendulum - The pendulum was discovered around 1602 by Galileo Galilei, and was adopted for time keeping by the Dutch mathematician and natural philosopher, Christiaan Huygens, who excelled in astronomy, physics, and horology.
The pendulum comprises a metal rod usually of brass or steel with a metal disk, known as a bob, at the end. The movement of the pendulum is driven by weights or a spring, and as a pendulum swings in a regular arc, it was found accuracy could be controlled to within a few seconds a week.
Timekeeping can be adjusted by changing the height of the bob on the rod, making the pendulum either swing slower or faster.
The disadvantage of the pendulum was that changes in temperature also changed the length of the pendulum, interfering with the accuracy of the clock, and so in the 18th century two types of mercurial pendulums were invented which countered the movement in the steel rod.
The pendulum was the world's most accurate timekeeping technology until the invention of the quartz clock, regulated by a quartz crystal, in 1927.
This item has been included into following indexes:
-
clocks, material or decoration
- marble or slate 425
- onyx 28
Visually similar items
Rare antique French mantle clock marked for Piolaine a Paris, has key and pendulum (in office), approx 44 cm high, 23 cm wide, 11 cm deep
Japy Freres late 19th century French gilt clock by Phillipe Mourey having hand painted floral porcelain panels, one with a maiden, another painted with a cherub, an enamel face dial, two applied figures of doves on a stepped base flanked by two angels. Hei
Societe Clusienne green marble mantle clock garniture with red marble inlaid detail, of classic French Art Nouveau shape, with a key & pendulum. Height 30 cm
A French late 19th century ormolu clock with 8-day strike movement, numbered 1577 24 8, and stamped A.B., within a five-pointed star, 35 cm high