Aurore After having tackled the building of a marine watch in 1756, Pierre Le Roy, 50 years old, has reached a new step last year. It is said that the chronometer he presented to the Académie Royale des Sciences is as precise and reliable as famous Harrison's H4. ¤ Le Roy already invented the detent pivot escapement, or detached escapement, that he presented the Académie in 1748, the temperature-compensated balance by using bi-metallic components, and lately the isochronou