Tortoise Shell Mantle Clock with Gilt Bronze Mounts
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.
- Tortoiseshell - Tortoiseshell is a translucent material that comes from the horny carapace of a certain types of turtles, including the hawksbill turtle. It is often therefore mounted on a colour underground - often red - or inlaid with gold or silver thread, as seen in Boulle furniture.
The texture and colour nuances of the material are extremely important. Heated tortoiseshell can easily be formed into various shapes. Like other natural materials, tortoiseshell becomes more beautiful with use. In a time before plastic, tortoiseshell was widely used for small objects such as combs and powder compacts.
In 1973, the trade of tortoiseshell worldwide was banned under CITES (The Convention on International Trade in Endangered Species). Prior to importing or exporting items containing tortoiseshell a CITES permit must be obtained. Tortoiseshell items cannot be traded on Ebay.
"Faux tortoiseshell", another case of man initiating nature, is made from old-style plastics such as celluloid and cellulos and is coloured with red, yellow and brown spots to imitate the genuine article. It is commonly used in glasses frames, musical instruments and costume jewellery. - Faux - A French word meaning "false", but when used in decorative arts, the intention is not to deceive, but to simulate the decorative effects of the more expensive material it is imitating. The term " faux bois" meaning "false wood" refers to a furniture item that has been decorated with a marked grain (woodgrain finish) to imitate a more expensive timber.
- Bronze - An alloy of copper and tin, traditionally in the proportions of about 9 parts of copper to 1 part of tin.
The discovery of bronze in Western Asia in the 4th century enabled people to create metal objects which were superior to those previoulsy possible because of its strength and hardness, and it has been used throughout the world for weapons, coins, tools, statuary and other decorative items.
It is very fluid in a molten state, and its hardness, strength when set, and non-corrosive properties makes it most suitable for casting sculpture. - 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:
Visually similar items
A small Louis XVI style gilt bronze mounted Boulle mantel clock, 19th century, 31 cm high
A large boulle mantle clock in the Louis XV manner, 20th century, German, with maker's mark for Fhs, the eight day movement clock of shaped form with a decorative pressed brass dial, enamel cartouches and Roman numerals, surmounted by a pagoda top and a ha
A 19th century French Boulle Mantel Clock. It has an eight-day gong striking movement with a cartouche Roman numeral dial mounted in a scarlet tortoiseshell and cut-brass boulle marquetry and a gilt metal mounted case. 33 cm high
Sonceboz Swiss bracket clock with an enamel face painted with Roman numerals, seconds numbers in fives from five to sixty and the twelve signs of the Zodiac, marked marked Huguenin, A. Neuchatel, with a wall hung shelf. Height of clock - 43 cm