It had been observed by ships of the First Fleet of convicts from England under the command of Arthur Phillip who was just leaving for Port Jackson after deciding that Botany Bay was unsuitable for settlement.
[8] His reading included Pierre Bulliard's Dictionairre Elementaire de Botanique (1783) and the works of Henri-Louis Duhamel du Monceau (1700–1782) who published works on forestry, naval architecture (especially relating to timber), agriculture, fruit tree cultivation, seed conservation and insect pests affecting seeds.
The first landfall was the Canary Islands, then the Cape of Good Hope followed by Van Diemen's Land (in Recherche Bay, Tasmania, named by d'Entrecasteaux after the flagship of his expedition ), then New Caledonia, Admiralty Islands, the Dutch colony of Ambon (where Delahaye exchanged seeds with the Dutch governor) then to south-western Australia discovering and naming Esperance Bay (d'Entrecasteaux now commemorating his second ship).
The next destination was Tonga where Delahaye collected breadfruit for transport to the Isle de France (now Mauritius), then to New Caledonia (where Kermadec, captain of the Espérance died), past Vanikoro Island (unaware that this is where La Pérouse had been shipwrecked) then through the Solomons, Trobriand Islands and finally, just before the death of d'Entrecasteaux in July 1793 from scurvy, surveyed the coasts of eastern New Guinea and northern New Britain.
The expedition was now under the new command of d'Auribeau the ships arriving at Sourabaya, Java, in 1793, to be told that France was now at war with European countries including Holland, Britain and Spain, also that Louis XVI had been guillotined and a French republic was now declared.
Its purpose was as a source of food and propagation material for the indigenous people, and also as a supply of provisions for future visiting European vessels.
[13] This was the first European garden on mainland Tasmania, planted just north of where the ships were anchored and, until recently, was last sighted by Lady Jane Franklin in the 1840s.
Delahaye's journal reports that he planted celery, chervil, chicory, cabbages, grey romaine lettuce, different kinds of turnip, white onion, radishes, sorrel, peas, black salsify and potatoes; he also had large quantities sewn in the woods, thrown at random where they might grow.
This time Delahaye tried explaining to the Aboriginal people, referred to today as the Lyluequonny, that the tubers, when cooked in fire embers, made fine eating.
[16] Calling in on the Adventure Bay side of Bruny Island Delahaye examined and tended the two pomegranate, one quince and three fig trees planted by Bligh's expedition in 1792.
[19]Archaeological work had failed to find artefacts and recognizable phytoliths, also the site seemed too close to the sea – even though the dimensions, layout and orientation approximated published descriptions by both Delahaye and Labillardière.
It is believed to be located in woodland near an intermittent stream, approximately 1 km north of Bennetts Point and 120 m inland (approx AGD66 E492782 N5180132), which is about 70-100 metres to the south-east of the stone structure discovered in 2002 (Galipaud et al 2007: 58 and 129).
[20]After several weeks of productive botanising in Recherche Bay, in 1793 the expedition ships set sail for Tongatapu (main island in the kingdom of Tonga) where Delahaye had specific instructions to collect quality breadfruit plants for transport to the Isle de France.
The plants he selected were maintained in specially designed rectangular wooden chests with drainage holes and a frame that would hold glass or grills to assist temperature regulation.
[17] Accordingly, in Tonga he collected 200 breadfruit plants, emulating similar work of David Nelson, gardener-botanist to British Captain Bligh on the Bounty.
[22] He then cared for the plants at sea eventually delivering them to Jean-Nicolas Céré at the Jardin des Pamplemousses on the Isle de France.
[24] When the collections from the expedition were finally returned to Paris they filled 36 trunks[25] and among the living plants brought back were two breadfruit trees.
[12][31][32] On 16 August 1879 the Museum National d'Histoire Naturelle purchased his herbarium, 84-folio catalogue and journal from the antiquarian bookseller Pironin for 295 francs.
[29] A manuscript of his seed collections is held in the Museum library (Notes des graines récoltées dans le voyage autour du monde).