1727-1807

Swiss clockmaker and chronometer maker.
Served his apprenticeship with his brother, Jean-Henri, a pendulum maker.
Established in Paris in 1745.
Disciple of Julien Le Roy.
Clockmaker to the Navy (nominated in 1762).
Clockmaker to the King (nominated in 1773).
Member of the Institute (nominated in 1795).
Member of the Royal Society of London.
Became a Knight of the Legion of Honour in the reign of Napoleon I.

Pioneer of chronometry in France (with Pierre Le Roy son). Made his first chronometer in 1754.

1768

Adopted perforated stones (rubies or sapphires) in clockmaking (English specialty initiated by Nicolas Fatio in 1704).

1782

Invention of a spring escapement. Invention concomitant but probably obtained independently from those of John Arnold and Thomas Earnshaw.

1786

Improved the self-compensating balance wheel.

Conducted considerable experimental research, including:

• Essai sur l’horlogerie (Essay on clockmaking) (1763)
• Traité des Horloges Marines (Treatise on Marine clocks) (1773)
• Histoire de la Mesure du Temps (The History of Time Measurement) (1802)

Ferdinand Berthoud is moreover the author of the watchmaking texts of the Encyclopedia of Diderot and d’Alembert.