Seth Thomas NSW Railway Wall Clock with Hexagonal Case
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.
- 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 oak cased drop dial wall clock, beech case, HAC movement. Height 31 cm
Early 20th century schoolhouse wall clock with dial marked Ansonia, 56 cm high
A quartz movement mantel clock, 15 cm high
An American regulator wall clock, circa 1900, Ansonia clock Company, New York, 'Regulator A' model, the large circular dial clock with Roman numerals and blue steel hands set within an octagonal frame above a shield style glazed section, with applied lette