Anchor escapement to only 4°-6°. In addition to the improved accuracy due to isochronism, this allowed clocks to use longer pendulums, which had a slower 'beat'. Lower air drag meant they needed less power to keep swinging, and caused less wear on the clock's movement. The anchor also allowed the use of a heavier pendulum bob for a given drive force, making the pendulum more independent of the escapement (higher Q), and thus more accurate. These long pendulums required long narrow clock cases. Around 1680 British clockmaker William Clement began selling the first commercial clocks to use the anchor escapement, tall freestanding
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