"Ferdinand Berthoud (18 March 1727, in Plancemont-sur-Couvet (Principality of Neuchâtel) – 20 June 1807, in Groslay (Val d´Oise)), was a scientist and watchmaker. He became master watchmaker in Paris in 1753. Berthoud, who held the position of Horologist-Mechanic by appointment to the King and the Navy, left behind him an exceptionally broad body of work, in particular in the field of sea chronometers." - (en.wikipedia.org 30.05.2020)
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