Harrison invents the gridiron pendulum In 1726, John Harrison created his Harrison of Barrow wooden regulator. This is one of a pair of regulator clocks by Harrison featuring his groundbreaking invention, the gridiron pendulum. This is a temperature-compensated pendulum designed to overcome the limiting effects of temperature fluctuations on pendulums. By laying the separate metal rods in a gridiron pattern, as shown in the above image, each of the two metals would counter the other’s reaction to any temperature change. The mercury pendulum that George Graham invented in 1721 was also a temperature-compensated pendulum designed to solve the same problem. Image Credit Harrison's gridiron pendulum. Still from animation created by John Redfern © The John C Taylor Collection Limited
