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Pendulum Clock
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here to see our selection of Pendulum Clock.
 Pendulum
clocks were invented by Christian Huygens in 1656. He used the model
of the pendulum that Galileo Galilei had introduced earlier. These
pendulum clocks, first invented back in 1656, were the most accurate
clocks up until 1930. Today, even good pendulum clocks are likely
to be off by about one minute every week.
To work well, the length of pendulum must stay constant, even when
the temperature changes. Therefore, most pendulum clocks have pendulums
made of both brass and steel because these two metals have differential
expansion - John Harrison used these metals to make a zero-expansion
pendulum. More modern pendulum clocks use a low-expansion alloy
like invar.
Lowering or raising the pendulum bob (the weight at the end of
the pendulum rod) can greatly change the time that your pendulum
clock keeps. If you raise the pendulum bob, the clock will keep
time faster. Lowering the pendulum bob will cause the clock to keep
time slower. Even having a dirty pendulum may cause your pendulum
clock to keep the wrong time - grime can interfere with airflow.
The time that pendulum clocks keep has improved over the years
since their invention in the 17th century, but they have never become
perfect. In the 20th century, W.H. Shortt invented a twin pendulum
clock. The twin pendulum clock had an accuracy up to one hundredth
of a second per day. In a twin pendulum clock, the pendulum’s
movement is monitored by electrical devices which drive a slave
pendulum which impulses the master pendulum.
Overall, there are many parts that make up a pendulum clock and
make it work - there are escapements and gear trains, phototubes
and electromagnets, and more, not to mention the hands of the clock
and all of the other gears.
Pendulum clocks may not be as great of timekeepers as newer quartz
clocks and atomic clocks, etc., but pendulum clocks can still be
found in many homes - pendulum clock have a classic look about
them that people just love. There are many pendulum clocks that
have been passed down for generations or will be passed down for
generations.
Pendulum clocks may not be able to keep time quite as well as other
clocks, but they can keep time quite excellently if you reset the
time every week or two. A pendulum clock only requires a little
bit of upkeep to receive such beauty in a timepiece. Every home
deserves to have a pendulum clock.
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