My desire to learn every thing concerning these people, and the strict look-out which it had been necessary to keep upon them, prevented me attending to any other business during their stay. According to Pobassoo, from whom my information was principally obtained, sixty prows belonging to the Rajah of Boni, and carrying one thousand men, had left Macassar with the north-west monsoon, two months before, upon an expedition to this coast; and the fleet was then lying in different places to the westward, five or six together, Pobasso's division being the foremost. These prows seemed to be about twenty-five tons, and to have twenty or twenty-five men in each; that of Pobassoo carried two small brass guns, obtained from the Dutch, but the others had only muskets; besides which, every Malay wears a cress or dagger, either secretly or openly. I inquired after bows and arrows, and the _ippo_ poison, but they had none of them; and it was with difficulty they could understand what was meant by the _ippo_. The object of their expedition was a certain marine animal, called _trepang_. Of this they gave me two dried specimens; and it proved to be the _beche-de-mer_, or sea cucumber which we had first seen on the reefs of the East Coast, and had afterwards hauled on shore so plentifully with the seine, especially in Caledon Bay. They get the _trepang_ by diving, in from 3 to 8 fathoms water; and where it is abundant, a man will bring up eight or ten at a time. The mode of preserving it is this: the animal is split down one side, boiled, and pressed with a weight of stones; then stretched open by slips of bamboo, dried in the sun, and afterwards in smoke, when it is fit to be put away in bags, but requires frequent exposure to the sun. A thousand trepang make a _picol_, of about 125 Dutch pounds; and one hundred picols are a cargo for a prow. It is carried to Timor, and sold to the Chinese, who meet them there; and when all the prows are assembled, the fleet returns to Macassar. By Timor, seemed to be meant Timor-laoet; for when I inquired concerning the English, Dutch, and Portuguese there, Pobassoo knew nothing of them: he had heard of Coepang, a Dutch settlement, but said it was upon another island. There are two kinds of trepang. The black, called _baatoo_, is sold to the Chinese for forty dollars the picol; the white, or grey, called _koro_, is worth no more than twenty. The _baatoo_ seems to be what we found upon the coral reefs near the Northumberland Islands; and were a colony established in Broad Sound or Shoalwater Bay, it might perhaps derive considerable advantage from the trepang. In the Gulph of Carpentaria, we did not observe any other than the _koro_, or grey slug.