On the 20th April, symptoms of dysentery showed themselves amongst the crews. Two days later therefore the vessel set sail, and it took seven good days to get beyond the straits of Madura. They returned along the north coast of Lombok, and passed through the Allas Straits, between Lombok and Sumbawa. The first of these islands, from the foot of the mountains to the sea, presents the appearance of a green carpet, adorned with groups of trees of elegant appearance, and upon its coast there is no lack of good anchorage, whilst fresh water and wood are plentiful. On the other side, however, there are numerous peaks of barren aspect, rising from a lofty table-land, the approach to which is barred by a series of rugged and inaccessible islands, known as Lombok, the coral-beds and treacherous currents about which must be carefully avoided. Two stoppages at the villages of Baly and Peejow, with a view to taking in fresh provisions, enabled the officers to make a hydrographical chart of this part of the coast of Lombok. Upon leaving the strait, Bougainville made an unsuccessful search for Cloates Island. That he did not find it is not very wonderful, as during the last eight years many ships have passed over the spot assigned to it upon the maps. The "Triads," on the other hand, i.e. the rocks seen in 1777 by theFreudensberg Castle, are, in Captain King's opinion, the Montepello Islands, which correspond perfectly with the description of the Danes.

Bougainville had instructions to survey the neighbourhood of the Swan River, where the French Government hoped to find a place suitable for the reception of the wretches then huddled together in their convict-prisons; but the flag of England had just been unfurled on the shores of Nuyts and Leuwin, in King George's Sound, Géographe Bay, the little Leschenault inlet, and on the Swan River, so that there was no longer any reason for a new exploration. Everything in fact had combined to prevent it; the delays to which the expedition had been subjected had indeed been so serious that instead of arriving in these latitudes in April, they did not reach them until the middle of May, there the very heart of winter. Moreover, the coast offers no shelter, for so soon as the wind begins to blow, the waves swell tremendously, and the memory of the trials which the Géographe had undergone at the same season of the year was still fresh in the minds of the French. The Thetis and the Espérancewere pursued by the bad weather as far as Hobart Town, the chief English station upon the coast of Tasmania, where the commander was very anxious to put in. He was, however, driven back by storms to Port Jackson, which is marked by a very handsome lighthouse, a granite tower seventy-six feet high, with a lantern lit by gas, visible at a distance of nine leagues.