The inhabitants of the Philippine Islands give the designation of salangan swallow to a little coast bird (the halcyon, or kingfisher), celebrated for the singular construction of its nest. These nests have been compared to those which the Greeks and Romans called halcyon’s nests; but this comparison is false, since the marine productions to which they gave this name are not birds’ nests but polypus’s, or the cylindrical covering of the polypi—the halcyonium—a kind of medicament, of which there were several varieties.[XX_103]
All travellers agree that the Chinese, and other eastern nations, have an extreme partiality for the salangan’s nest, as a delicious seasoning for their viands, and that they value it excessively; but they differ strangely as to its nature, its form, and the places where it is found.
According to some, the material of these nests is a froth of the sea, or the spawn of fish, and strongly aromatic. Others say it has no taste. Some pretend that it is a juice gathered by the salangans from the tree called salambouc; some maintain that it is a viscous humour that they give out from the beak at a certain period of the year; and, lastly, many affirm that these birds compose it entirely from the remains of fish-zoophytes.
With respect to the form, some say that it is hemispherical; others that it resembles a shell valve.
As to the places where the salangans build their nests, some observers assure us that it is fixed on the rocks a little above the level of the sea; in the hollows of those same rocks; and, lastly, that they conceal them in holes which they burrow under ground. According to Kœmpfer, these nests, so far as they are known to us, are nothing more than a preparation concocted from the flesh of the polypi.
The celebrated traveller Poivre, while occupied one day in picking up shells and coral near Java, penetrated a rather deep cavern at a short distance from the sea shore, and found the sides of it covered with little nests, in the form of a deep shell, firmly fixed to the rock. These nests were taken on board, and several persons who had been in China immediately recognised them as being identical with those that the Chinese seek with such avidity. The birds which had built them were true swallows, of about the size of the humming bird. Poivre adds that, in the months of March and April, the sea from Java to Cochin China is covered with spawn, which has the appearance of half-dissolved glue, and that he had learned from the Malays and the Cochin Chinese that the salangan builds its nest with this spawn. All agreed on this point. The bird picks it up as he skims the water, or from the rocks where the spawn coagulates. It is at the end of July and the commencement of August that the Cochin Chinese collect the nests, and, as the young birds are hatched in March and April, the species do not suffer by it.
By the subsequent examination of these nests it was found that they presented the form of the half of a hollow, lengthened ellipsoid. They are composed, externally, of very thin laminæ, nearly concentric, and laid one over the other. The interior presents several layers of irregular net-work, superposed one over another, and formed of a multitude of threads of the same matter as the external laminæ, and which cross and re-cross in every direction.
Their composition, which has a slight taste of salt, is of a yellowish white and demi-transparent; it softens in warm water without dissolving, and increases in volume. It is a substantial food, and would be excellent for persons suffering from exhaustion, whose debile stomachs ill perform their functions. Poivre declares that he never eat anything more fortifying than a pottage made with these nests and some good meat.
The salangan nests are of two sorts—the white and the black. It appears that the white nests are those of the same year, and that the black ones belong to an epoch less recent. The birds are engaged about two months in preparing them, and the Chinese do not take them away until the young ones are feathered, and begin to be pretty strong on the wing.[XX_104]