"The trade in these nests, which some years ago was of little importance, has been greatly on the increase for some time. The price is constantly rising in China, and Batavia is the principal market for them. The company having abandoned it, the inhabitants derive sufficient advantage from it to diminish the exportation of specie, which is highly prejudicial. It is now very well ascertained that the species of swallow which builds these nests is not to be found in China. "Linnaeus, in his Systeme Naturel, characterizes this swallow, which he calls the hirundo esculenta, by white spots only on the feathers of the tail. But those birds of Java, which construct the nests in question, have no spots either on their tail or elsewhere. The feathers of the tail are entirely of one colour, that is, grey, approaching to black on the upper, and a lighter grey on the under surface. "Rumph says, in speaking of these apodes marinae, that the feathers of their tail are spotted, and that the breast has black and white spots. "Valentyn in his description of the small swallow which builds the eatable nests, says nothing of spots, and only states that the body is veined white and black. "If these differences are allowed to be essential, it will follow that there must be two kinds of these swallows, the one with a spotted breast, and having white spots on the tail, the other without either. It is possible, even, that there may be a third variety, that called momos, or bocrongitams. These likewise form their nests of part of their food; but mixed with so much impure matter that no use can be made of them. Care is taken, therefore, to drive them away, that they may not injure the nests of the better species. They are readily known from these latter by their superior size, and their legs being provided with small feathers down to the feet. "In the kingdom of Tonquin, and in China, there is a great demand for these nests of the salanganes. They form their most exquisite food, and they attribute to them the property of strengthening the stomach, and of being a powerful aphrodisiac. They are preserved for the tables of the King, and those of the principal nobles who are able to procure them. They are diluted, made into gravy or soup, and mixed with all sorts of choice aliment, and every kind of taste is imputed to them. "In the state in which the salanganes are sold, they bear a close resemblance to the half of a preserved citron, both in size and shape. They are put into small boats, which the people of the country are sufficiently dextrous in piloting through the rocks where the nests are found. The King of Cochin-China retains in his own hands, exclusively, the portion of this trade which belongs to him, as the most precious production of his dominions, and of which the sale is most to be relied on." Note VII.--Page 18.