Anchor escapement clocks. During the 19th century the deadbeat form gradually took over in most quality clocks, but the anchor form is still used in a few pendulum clocks today. The anchor escapement is reliable and tolerant of large geometrical errors in its construction, but its operation is similar to the old verge escapement, and retains two of the major disadvantages of the verge: The above two disadvantages were removed with the invention of an improved version of the anchor escapement: the deadbeat or Graham escapement. This is often erroneously credited to English clockmaker George Graham who introduced it around 1715 in
Escapement of this escapement over the lever are of an uncertain value. In an effort to attract publicity, in recent decades some high end mechanical watch makers have introduced new escapements. None of these have been adopted by any watchmakers beyond their original creator. Based on patents initially submitted by Rolex on behalf of inventor Nicolas Déhon, the constant escapement was developed by Girard-Perregaux as working prototypes in 2008 (Nicolas Déhon was then head of Girard-Perregaux R&D department) and in watches by 2013. The key component of this escapement is a silicon buckled-blade which stores elastic energy. This blade is flexed