The first escapement known, used in most clocks until the introduction of the recoil anchor escapement in the third quarter of the 17th century. By the end of the 18th century the verge was rarely made, and many earlier verge-escapement clocks were modernised by fitting an anchor escapement. A tooth of the escape wheel gives impulse to the pallet flag. On completion of impulse, a tooth drops on to the pallet, receiving recoil as the pendulum forward swing continues. When the motion of the pendulum is reversed, the pallet receives impulse until the tooth escapes, and the next tooth drops on to the other pallet, which receives recoil until the pendulum reverse swing is complete, the cycle then continuing. The verge escapement has a undeservedly bad name for timekeeping. A clock in good condition, well maintained, will average one or two mintues of error per week over long periods.