Regulator clocks
Also known as pendulum clocks, were first conceived of in the 17th century, but these early pieces had escapements that made them inaccurate time keepers. Pendulum clock timekeeping improved with the invention of the anchor escapement in the early 18th century.
However, with the quest for even better timekeeping, the weight-driven regulator clock was invented in 1715 and is credited to George Graham who used the deadbeat escapement invented in 1675 by Richard Towneley. To increase accuracy additional features such as calendars and planetary positions were excluded, and each of the clock’s hands was worked by a different mechanism. Further improvements were made by John Harrison and other clockmakers and by the middle of the 18th Century, their clocks were accurate to within a few seconds per week.
Pendulum clocks were very expensive as they were handmade by individual craftsmen and featured ornamentation and decoration to show their value as status symbols. This changed in the 19th Century when new production techniques meant that parts could be manufactured in factories making them cheaper to produce and so more widely available.
The form particularly flourished in Vienna where regulator wall clocks were considered to be so accurate that they were used as the main timepieces in important public places such as post offices and railway stations.
Pendulum clocks remained the world standard for accurate timekeeping for over 270 years until they were replaced with the quartz clock in 1927.