Escapement wheels, which because they lacked a balance spring had no natural "beat", so there was not much incentive to improve the escapement. The great leap in accuracy resulting from the invention of the pendulum and balance spring around 1657, which made the timekeeping elements in both watches and clocks harmonic oscillators, focused attention on the errors of the escapement, and more accurate escapements soon superseded the verge. The next two centuries, the "golden age" of mechanical horology, saw the invention of perhaps 300 escapement designs, although only about 10 stood the test of time and were widely used in clocks
Coaxial escapement beat movements, he has also noted that they aggravate the problem of sliding friction in the escapement (at the escape teeth and pallets). Higher beat movements produce increased speed and pressure at these critical surfaces." Coaxial escapement The coaxial escapement is a type of modern watch escapement mechanism invented by English watchmaker George Daniels. Invented around 1974 and patented in 1980 by English watchmaker George Daniels, the coaxial escapement is a modification of the lever escapement with some features of the detent escapement. Considered by some to be one of the most significant horological advancements since the invention of the