Heraldry, according to their several kinds, represent either the contemplative or active life. They are the emblems of liberty, expedition, readiness, swiftness, and the like, and are therefore more honourable bearings than fishes. Birds must be borne in coat-armour, as is best fitting the propriety of their natural actions. Such as are either whole-footed, or have their feet divided, and yet have no talons, are said to be membered; but the cock, and all birds of prey with sharp and hooked beaks and talons for encounter or defence, are said to be armed. In the blazoning of birds, if their wings be not displayed, they are said to be borne close.

Bird's-Nests, Edible, the nests of a small Indian swallow, which are eaten as a delicacy. These birds abound on the sea-coasts of China and in Java at certain seasons of the year. They build in the rocks, and fashion their nests out of a gelatinous matter which they find on the shore. According to Kempfer, this substance is mollusc or sea-worms; M. le Poivre supposes it to be fish-spawn; and according to Linnæus, it is a kind of medusa or jelly-fish. The nests are hemispherical, of the size of a goose's egg, and in substance much resemble ichthyocolla or isinglass. They are sent to all parts of the world, and are highly prized as a luxury. They abound in Sumatra, particularly about Croe, near the south end of the island. Four miles up the river of that name is a large cave, where the birds build in vast numbers. The nests are distinguished into white and black; but of these the former are more scarce and valuable, being found in the proportion of only one to twenty-five. According to Marsden's account, the white nests sell in China at the rate of 1000 to 1500 Spanish dollars the pecul; the black are disposed of at Batavia for about twenty dollars the same weight, and manufactured into glue. The difference of colour is said to be owing to the admixture of feathers. By steeping for a short time in hot water, the black nests are said to become in a great degree white. The natives enter the caves with torches, and by means of a ladder made of a single bamboo notched, they take the nests, which adhere in masses from the side and top of the rock. The more frequently and regularly the cave is stripped, the greater proportion of white nests is found; for which reason they destroy the old nests, in order that they may find their place supplied by white nests the next season. (See also Crawford's Eastern Archipelago, vol. iii. p. 432; and Count Hogendorp's Coup d'œil sur l'île de Java, p. 291.)