Editing Carillon (section)

===Mechanization with clock and playing drum===
Carillons may also feature an automatic mechanism by which simple tunes or the [[Westminster Quarters]] are played on the lower bells.{{sfn|Lehr|2005|pp=59–60}} The mechanism on European carillons is often a playing drum, which is a large metal cylinder connected to a clock mechanism.{{sfn|Lehr|2005|pp=87–88}} Metal pegs are screwed onto the outside of the drum. When the clock mechanism sets the drum in motion, the pegs catch onto levers, connected to hammers that rest just a short distance from the outside of the bell. The hammers are briefly raised, and then fall onto the bell as the peg continues to rotate away from the lever.{{sfn|Lehr|2005|p=88}} The pegs are arranged such that simple tunes can be programmed to play at specific quarter hours.{{sfn|Lehr|2005|pp=90–95}} In North America, automatic playing drum systems are not common; instead, carillons may have pneumatic systems which ring the instrument.{{sfn|Lehr|2005|p=98}}