The Deadbeat Escapement: George Graham's 1715 Triumph

When listening to a grandfather clock, you hear the distinctive cadence of passing seconds. But if you watch the second hand closely on an antique timepiece from the 1680s, you will witness something strange: as each second ticks, the hand jumps forward, recoils slightly backward, and then stops.

This phenomenon—known as anchor escapement recoil—plagued early pendulum clocks until English watchmaker George Graham introduced the deadbeat escapement in approximately 1715.

The Problem with Robert Hooke's Recoil Anchor In 1671, Robert Hooke invented the anchor escapement. Two curved pallets rocked on an arbor above a toothed escape wheel. While an enormous improvement over older verge escapements, the sloping faces of Hooke's pallets forced the escape wheel to rotate backward by a fraction of a degree each time a tooth caught a pallet.

This backward push (recoil) disturbed the natural harmonic motion of the pendulum. Every tick pushed energy back through the entire wheel train, causing friction and rate variations whenever drive weights wound down.

Graham's Elegant Deadbeat Solution George Graham realized that pallets should have two distinct geometric surfaces: 1. **The Dead Face (Locking Phase):** An arc curved with its center point exactly on the pallet arbor axis. When an escape tooth strikes this face, the wheel locks completely dead—neither advancing nor recoiling—while the pendulum completes its swing. 2. **The Impulse Face (Driving Phase):** A beveled incline that gives the pendulum a gentle push just as the pallet releases the tooth.

Because the escape wheel stops dead on each beat without bouncing backward, Graham called his invention the "deadbeat" escapement.

Why Regulator Clocks Became the World Standard Graham's deadbeat escapement allowed pendulum regulator clocks to achieve an unheard-of accuracy of less than one second of error per week. For the next two hundred years—until the invention of quartz crystals and atomic clocks—astronomical observatories around the globe, including the Royal Observatory at Greenwich, calibrated their star-transit sightings using deadbeat regulator clocks.

When you switch between Continuous Sweep and Mechanical Tick modes on our main analog clock, you are choosing between modern electronic glide and George Graham’s 300-year-old deadbeat horological legacy.