It has been long disputed whence this industrious little warbler obtains the material for his nest, and it was in all probability the circumstance that it was generally believed to consist of particles of sea-weed, fish-roe, and marine animalculæ of the _medusa_ class, which secured for these nests such a celebrity among Chinese gourmands. A German naturalist, Professor Troschel of Bonn, affirms however, on the strength of an analysis of these nests, that the notion hitherto prevalent as to the component parts of these nests is entirely erroneous, as they consist of nothing else than a thick, glutinous slime, secreted from the salivary glands, which, at the period when the Indian swallow builds its nest, swell out into large whitish masses. This slime, which is susceptible of being drawn out in long filaments from the bill of the animal, is quite analogous to gum Arabic. Whenever the bird is desirous of constructing its nest, it causes this salivary substance, which at that period is copiously secreted, to adhere to the crags, till its elegant nest is finished. One of the days during which the frigate lay in Nangkauri harbour, the geologist of the Expedition made an excursion in a native canoe along the coasts of Kamorta and Tringkut, as these islands at the points where the shores are precipitous furnish the only possible geognostic facilities, the forest or the thick covering of vegetation in the interior of the island quite concealing the geological conformation. Our Chinese friend Bing-Hong aforesaid accompanied him in the capacity of interpreter. When the geologist had got some distance from the frigate, he found that the natives had not abandoned their villages, and to this one alone of our fellow-travellers, manned and rowed along by natives, did some of the women become visible. They were as tall as the men, and quite as loathsome in appearance, the mouth similarly disfigured by betel-chewing, but the hair cut short. Around the body they wore a petticoat of red or blue cloth, reaching from the loins to the knee.