De la Mesure du temps, ou supplément au traité des horloges marines, et à l'essai sur l'horlogerie ...
Ferdinand Berthoud's 1787 Paris treatise on time measurement, a supplement to his work on marine clocks, printed for Mérigot, Didot fils and Jombert jeune for clockmakers and navigators. Its engraved plates show clock and chronometer trains drawn in elevation, with lettered gears, fusees and escapements. A designer could draw on their dense, precise linework and the mechanical diagram conventions of Enlightenment engraving.















