Three French Sailing Ship Performance Trials
A French naval officer, Lieutenant de Vaisseau Verdub de la Crenne, with two civilians, undertook a series of trials to understand the capabilities of three pre-clipper ships in 1771. The article introduces those who undertook the trials, and the results that were found. The paper explains what can be learnt from three scientific sailing ship performance trials conducted by French naval officers. The first concerns the trials conducted on board the frigate Flore in 1771. The commander, Lieutenant de Vaisseau Verdun de la Crenne’s main aim was to test the chronometers designed by Bouguer and Leroy but he used the voyage as an opportunity also to test Bouguer’s theories on the most efficient bracing angles for square sails. He found clear differences between theory and practice. In 1836 Capitaine de Vaisseau Thomas Letourneur while in command of the Astrée attempted to ascertain the most efficient course to use when sailing down wind. Finally in 1872-3 Lieutenant de Vaisseua Armand Paris on the training ship Jean Bart made a series of observations intended to establish the best sail plan to use in different wind speeds and sea conditions. While it was very difficult to standardise observations to reach conclusions, these observations showed that in light winds old wooden ships sailed better than large steel-hulled vessels with the reverse being the case in heavy weather.