Voyage fait par ordre du Roi en 1768 et 1769 à différentes parties du monde, pour éprouver en mer les Horloges marines inventées par M. Ferdinand Berthoud. Paris: Imprimerie Royale, 1773.
Volume 1 only (of 2). 4to (190 x 250 mm). [4], lxxx, 804 pp. Period calf gilt. Lacking all 5 maps, wormhole through gutter, damp- and waterstains to final 50 leaves, binding worn, contents working loose.

FIRST EDITION, charting a key moment in the longitude race. Ferdinand Berthoud, Pierre Le Roy and John Harrison were competing to develop the perfect marine chronometer. The Comte de Fleurieu, Lieutenant of the Royal Ships, took Berthoud's marine clocks nos 6 and 8 on his voyage to Martinique, Santo Domingo, Porto Rico, Havana, Jamaica, Colon, New Orleans, New York, Boston, and Newfoundland. He returned to Aix on October 11, 1769. Berthoud's design of a box to contain the chronometer became the standard, and using his timepiece Fleurieu was able for the first time to calculate highly accurate positions of the ports visited. Rare at auction. Sabin 24750.