27 October 2014
In the past, marine chronometers were indispensable to navigation, as they were used to determine longitude in the open sea. So they had to be extremely precise (a deviation of just one second translated into an error of position of 500 meters), clearly legible and always reliable over long voyages. They were made by just a few, prestigious clock- and watchmakers: like L.Leroy, already specialized in the sector in the second half of the 18th century, official watchmaker to the French Naval Ministry since 1835 and supplier of numerous merchant and naval fleets until 1980. It is keeping the tradition of these instruments for navigation alive today with the Marine Deck Chronometer: the 43-mm-diameter case in white (or pink) gold, water resistant to 10 atmospheres, contains an automatic mechanical movement with silicon components. The hand-decorated dial features a large second and power reserve indicator. Impeccable in its finishing, its accuracy is attested by the official chronometer certificate of the National Observatory of Besançon.