Breguet, “Horloger de la Marine” On October 27, 1815, Abraham-Louis Breguet (1747-1823) was appointed chronometermaker to the French royal navy by Louis XVIII (1755-1824), King of France (1814-1815 and 1815-1824). It was not only a prestigious honour but also an essential state function. At that time, marine chronometers were of vital importance to fleets as they could determine the position of ships at sea. They had to be accurate and resist the constant movement of a ship. Involved in this task, Breguet designed a number of outstanding marine chronometers. They were mounted on special boxes made of mahogany or walnut wood. A gimbal suspension system kept the chronometers level whatever the circumstances. Breguet producing marine chronometers with twin going barrels of a similar type since the early 19th century. Typical features are the two barrels and the lentil-shaped separate plate for the escapement. Despite the complex construction ?? which has, for example a very intricate holder for the balance that can be adjusted with three screws ?? the design allows for a very efficient production process. The train is not fitted between the main plates but sits underneath the dial, which makes it easily accessible. The escapement can be worked on without touching the rest of the movement ?? a locking lever stops the movement as soon as the balance mechanism is removed.