SWALLOW. 295 



four miles up a river of that name ; but they are not peculiar to the 

 above places, being common from Java to Cochin China, on the 

 north ; and from the point of Sumatra west, to New Guinea east, 

 where the sea is said to be covered with a viscous substance like half 

 melted glue, which the bird is supposed to take up from the surface 

 with its bill during flight, or pick it from the rocks when left there 

 by the waves. 



So far we have given the accounts furnished to us by various authors, 

 in which there appears nothing unsatisfactory or contradictory to our 

 supposition, that the bird in question may make the above mentioned 

 sea slugs their principal food, however directly or not it may con- 

 tribute to form the nest ; much light, however, has been thrown on 

 this matter by the researches of Sir E. Home,* who has investigated 

 the structure of the stomach of a bird of this kind, said to fabricate 

 edible nests ; and producing a conviction, that the materials for foran- 

 ing the said nests are produced from the glands of the stomach of 

 the bird itself, which are of a peculiar structure, and totally different 

 from those of the Common Swallow, or others of that Genus; and by 

 no means merely carried in the mouth of the bird, to be deposited 

 against the sides of the place to which the nest is fixed, as in the case 

 in respect to the mud from which the nest of the European Martin is 

 constructed. 



The best nests, or those of a pure white, and free from mixture, 

 sell in China from 1000 to 1500 dollars the pickle;f the black or dirty 

 ones for only 20 dollars. These last arise from age, or being mixed 

 with dirt or feathers, and the gatherers beat down all the black ones 

 they can get at, in hopes, that from the necessity of the birds making 



* Philos. Trans. Vol. for 1817, p. 335. pi. xvi. But his bird can scarcely be the same 

 with either of the two here described ; as it is said to be twice as large as our Swallow ; there- 

 fore must differ materially from any, which have come under our observation, and unfortu- 

 nately the description of the plumage of the bird is omitted. In size it seems to be nearest 

 to the Klecho. 



f Pickle, or Pekul, is about 125 pounds, or as Dampier says, 300 picks are equal to 

 396 pounds English weight.— See Voy. ii. 132. 



