In 1767 he sailed near Rockall, or Rokol. Although he may not have approached within sight of it, or even within 150 miles, he appears to have had good information regarding it. His charted position for it was only 16 miles north of its actual position and he accurately described its appearance[1] and the nearby Helen's Reef: "East of Rokol, ¼ league away, there is a submerged rock over which the water breaks".[2] In 1771, he published a map of the area.
Discovery of the Kerguelen Islands
In early 1772, he was assigned command of the third French expedition sent in search of the fabled Terra Australis with the fluytsFortune and Gros Ventre. The expedition discovered the isolated Kerguelen Islands north of Antarctica in the southern Indian Ocean and claimed the archipelago for France before returning to Mauritius. He was accompanied by the naturalist Jean Guillaume Bruguière. On a follow-up expedition to the Kerguelen Islands in 1773, he was accompanied by the astronomer Joseph Lepaute Dagelet. Kerguelen, a supporter of slavery, used "Blacks in difficult moments in order to preserve his white crew".[3]
In his report to Louis XV, he greatly overestimated the value of the Kerguelen Islands; consequently, the King sent him on a second expedition with the 64-gun Roland and the 32-gun frigate Oiseau, but was again unsuccessful in finding Terra Australis. By now, it had become clear that the Kerguelen Islands were desolate and quite useless, and certainly not Terra Australis. Upon his return, Kerguelen was court-martialled in Brest on 15 May 1775 by a council of war presided over by Vice-Admiral Anne Antoine, Comte d'Aché for transporting 200 slaves on Roland from Madagascar to sell in French colonies in defiance of Louis XV, who had issued regulations ordering French Navy officers not to trade in slaves. At the court-martial, his defence lawyer minimised Kerguelen's slave-trading activities by stating that it was only "Eight or nine negroes that the pilot’s assistant bought on Kerguelen’s behalf". Although several other naval officers, many of whom were stationed at Rochefort, had traded in slaves, he was found guilty on 25 May 1776 and sentenced to six years imprisonment.[4][5]
Martin-Allanic, Jean-Étienne (1964). Bougainville Navigateur et les Découvertes de son Temps (in French). Paris: Presses Universitaires de France. ISBN9787240006214. OCLC729759706.
