<P> Cable clocks are wound by inserting a special crank (called a "key") into holes in the clock's face and turning it . Others, however, are chain - driven, meaning that the weights are suspended by chains that wrap around gears in the clock's mechanism, with the other end of the chain hanging down next to the weight . To wind a chain - driven longcase clock, one pulls on the end of each chain, lifting the weights until the weights come up to just under the clock's face . </P> <P> In the early 20th century, quarter - hour chime sequences were added to longcase clocks . At the top of each hour, the full chime sequence sounds, immediately followed by the hour strike . At 15 minutes after each hour, 1 / 4 of the chime sequence plays, at the bottom of each hour, 1 / 2 of the chime sequence plays, and at 15 minutes before each hour, 3 / 4 of the chime sequence plays . The chime tune used in almost all longcase clocks is Westminster Quarters . Many also offer the option of Whittington chimes or St. Michael's chimes, selectable by a switch mounted on the right side of the dial, which also allows one to silence the chimes if desired . As a result of adding chime sequences, all modern mechanical longcase clocks have three weights instead of just two . The left weight provides power for the hour strike, the middle weight provides power for the clock's pendulum and general timekeeping functions, while the right weight provides power for the quarter - hour chime sequences . </P> <P> The Oxford English Dictionary states that the popular 1876 song My Grandfather's Clock is responsible for the common name "grandfather clock" being applied to the longcase clock . </P> <P> The song was composed by an American songwriter by the name of Henry Clay Work who discovered a long grandfather clock in The George Hotel in Piercebridge, in County Durham in England . When he asked about the clock, he was informed that it had two owners . After the first owner died the clock became inaccurate and when the second owner died, the clock stopped working altogether . The story inspired Henry to create the song . </P>

Where did the term grandfather clock come from