1820 James Oatley Colonial Australian Cedar Longcase Clock

• Back Plate - On many types of clocks, the movement operates between two plates, usually made of brass, one at the back, and the other at the front, which forms a mount for the dial.
  
  On English bracket, mantle and table clocks the backplate was often visible through a glass door or panel from the late 17th century, and could be profusely engraved with scrolling decorations, flowers, foliage, birds, and figures. The engraving could also include the maker?s name.
  
  The amount of engraving reduced and became simpler as the 18th century progressed, and by 1800, had been reduced to a border, often with the maker's name in the centre. By the early 1800s all decoration had ceased, and only the maker's name was added, and by the Victorian era, most bracket, mantle and table clocks had no engraving.
• Hood - In longcase clocks, the hood is the wooden case that surrounds the works and dial, and includes the glass front, which is usually hinged, so the door can be opened to wind the clock or adjust the time. In 18th and 19th century longcase clocks the hood usually slides forward for removal, allowing access to the works.
• Maintaining Power - A horological term to describe a subsidiary driving force such as a spring or additional weight in a clock, which keeps the movement going while the mainspring is being rewound.
• Casuarina - Casuarina, is also known as beefwood (because of its appearance) she-oak, swamp oak, river oak, forest oak and Botany Bay wood. It is a native Australian hardwood, red brown in colour with dark flecks.
• Important - Important is a word used in the antique trade to indicate an object should be ranked above other similar objects, and is therefore more valuable.
  
  The object could be considered important because it is by a famous designer or maker, has been shown at a major exhibition, is of exquisite workmanship, is rare or is a "one-off", was made for an important patron, and so on.
  
  Even further up the pecking order are objects that are described in catalogue descriptions as highly important or extraordinarily important.
• 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.
• Movement - The technical name for the workings of a clock or watch, and does not include the dial or case.
• Date Aperture - A date aperture is a cut out section in the face of a watch or clock, displaying the day of the month.

This item has been included into following indexes:

• clocks, grandfather / longcase, country of origin
  • Australian 13
  • Regency 14
• clocks, grandfather / longcase, period or age - 18th century, other 111
• Oatley, James (Australia) - clocks, maker or retailer 3