Verge escapement
![Verge escapement and balance wheel from an early pocketwatchVerge and foliot escapement from De Vick clock, built Paris, 1379, by Henri de Vick](/Images/godic/202502/19/Verge_watch_escapement2640.png")
![](/Images/godic/202502/19/De_Vick_Clock_Verge_&_Foliot2640.png")
![One of the earliest existing drawings[4] of a verge escapement, in Giovanni de Dondi's astronomical clock, the Astrarium, built 1364, Padua, Italy. This had a balance wheel (crown shape at top) instead of a foliot. The escapement is just below it. From his 1364 clock treatise, Il Tractatus Astrarii.](/Images/godic/202502/19/Verge_escapement_Giovanni_di_Dondi2640.jpg")
![Salisbury cathedral clock, 1386?, England, shows what the first verge clocks looked like. The few original verge clock mechanisms like this surviving from the Middle Ages have all been extensively modified. This example, like others, was found with the original verge and foliot replaced by a pendulum; a reproduction verge and foliot was restored in 1956 (visible top center).](/Images/godic/202502/19/Salisbury_Cathedral,_medieval_clock2640.JPG")
The verge (or crown wheel) escapement is the earliest known type of mechanical escapement, the mechanism in a mechanical clock that controls its rate by allowing the gear train to advance at regular intervals or 'ticks'. Its origin is unknown. Verge escapements were used from the 14th century until the mid 19th century in clocks and pocketwatches. The name verge comes from the Latin virga, meaning stick or rod.