Le Roy Invents the Detent Escapement In 1748, the detent escapement was invented by French watchmaker Pierre Le Roy. It was favoured for use in marine chronometers because it had certain advantages. For example, the balance wheel can move freely for the majority of its cycle, thus maximising its isochronous swing. Also, the pallet and escape wheel are almost nearly parallel to one another, thus there is very little friction. Despite these advantages, Le Roy’s design was considered ineffective. It was not until 1775 that the British clockmaker John Arnold improved it. Le Roy’s invention was important, because it laid a crucial foundation for the precision ultimately achieved by marine chronometers. Image Credit Le Roy's detent escapement illustration. Ferdinand Berthoud, Public domain, via Wikimedia Commons
