The “hideous” state of health in which the crew of his fleet is reduced, forces Captain Yves Joseph de Kerguelen-Trémarec to release at Dauphine Island (Madagascar) on February 21, 1774, The island Aiguillon, so called by Benyowski in honor of the Duke of Aiguillon (1720-1782), his protector. It should be pointed out that the island of Aiguillon where this harbor is located, is a rocky and wooded island located at the bottom of the bay of Antongil. It receives successively the names of the island of Forbans by Cossigny, d’Aiguillon by Benyowski, d’Anjou by Hermitte. And from 1960, she is restored her old name of Nosy Mangabe.
Because of the rains and the time taken to mount the tents, he can not disembark his men until 26 February: first 98 men among the most sick and 50 the next day. However, Benyowski can only supply him four oxen in ten days, while he needs one a day for his sick. The reason for this is simple: when the “war machine” and the guns are landed, the local population moves away and does not want to sell anything to Benyowski. “The warrior chieftains held continual assemblies, which they called palaver, to concertate the means of injuring him. Kerguelen then decided to send men directly to the villages along Antongil Bay to try to buy poultry and oxen and he easily obtained the quantity he wanted.
In his “Memory on the Isle of Madagascar named Isle Dauphine”, he specifies that the Bay of Antongil is “the attic or the store of all the neighboring ports”. He explains: “It is from this bay that rice and cattle are drawn. The islanders in this part are farmers. The lands are beautiful, elevated, and watered by rivers on all sides, and nature produces, as it were, all without the aid of art. ” The archivist-palaeographer Jean Valette emphasizes that the richness of the East coast, especially of the Bay of Antongil, has always struck the navigators since the sixteenth century. In 1598, a Dutch captain who declares having seen lights all around this bay, calls Marosy Island “the mountain of fruits”, as it is rich in oranges, lemons, bananas, sugar canes.
Addressing the strategic position of the roadstead of Aiguillon, Kerguelen mentions that the port of Boynes (name given by Benyowski to the village of Ambatomasina in honor of the Minister of Marine) is safe and convenient to receive a beautiful squadron. The harbor itself can put fifty ships of war away from winds and hurricanes. “We see that this harbor and harbor can be very useful in times of war. Squadrons can come and repair after fights or storms. There will be provisions and refreshments. They will be safe there in all seasons, and will not see a squadron perish on its anchors. “
Kerguelen proposes to supply this squadron with seven or eight Bourbon families (“where there are many in poverty”) to raise poultry and to cultivate gardens which are the only thing missing in the bay Antongil. And to make the place impregnable, he suggests building a fort on the island of Aiguillon and another on the Great Earth next to the village of Ambatomasina.
“But to be safe from a hand, it is now only a question of placing twenty-four pieces of big guns and four mortars on the isle of Aiguillon, this can and must be done at The first campaign; Then the commander of the island of Aiguillon with three hundred men will be protected from being attacked by a squadron of six ships of the line, which is about the number which the English employ on the Indian seas in time of war.”
He specifies that the ships of the king will thus be sheltered at the same time from the winds and the enemies. In addition, the crews will find vegetables, food and refreshments. “You can make arack (or arac, a Creole word for a spirituous liquor from fermented rice, Jean Valette), which is given instead of brandy. “He assures that it is also possible to make cured meats and biscuits with corn that is excellent and can be kept for a long time.
However, the place does not have that benefits. Because the port of Boynes is in a bay that is “leeward of the whole island”. Thus, the wind which is always favorable to enter, oblige to tack to go out. “The enemy can anchor throughout the bay about five or six miles from the ground and wait for the buildings to pass. “
As merchant ships are not as good sailboats as warships, they may take a month to get out of the bay. What is detrimental to trade, by the consumption of provisions, the length of the crossings, and the fatigues which are contrary to the health of the crews. And it is all the more unfortunate that one can establish in Antongil Bay a very brilliant trade with the sugar cane and the coffee which grow well there, the indigo which is magnificent there, Other products of export such as cotton, tobacco, incense, amber, rock crystal, silver lead and other precious things that can be supplied inside the country which is unknown to us … “