Cast Iron Armorial Wall Clock

• Movement - The technical name for the workings of a clock or watch, and does not include the dial or case.
• Armorial / Armourial - Bearing a coat of arms. Coats of arms came into general use by feudal lords and knights in in the 12th century, and by the 13th century, arms had spread beyond their initial battlefield use to become a flag or emblem for families in the higher social classes of Europe. They were inherited from one generation to the next. When a family crest is used on individual items of silver or furniture it is an indicator of the aristocratic standing of the family represented.
  
  Armorials were also used to decorate mass produced ceramic souvenir ware by such companies as Goss, Carlton & Shelley, and in these cases the coats of arms displayed were of boroughs and cities.
• 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, type
  • dial 274
  • wall 829