244 
COMPENDIUM OF GEOGRAPHY AND TRAVEL 
dammar and gutta-percha—the latter a product of great 
value: all these are largely exported. Considerable 
quantities of beeswax are brought down to the coast by 
the natives, especially in North Borneo; but, excepting 
rattan, by far the most important and valuable article of ex¬ 
port from this district is birds’ nest. Probably not less than 
fifteen or twenty thousand pounds’ worth are annually 
sent to Singapore and China. The nest in size and shape 
may be compared to the vertical half of a small teacup, 
and its appearance is that of having been constructed of 
threads or fibres of gelatine. The best are white and 
glassy-looking, and may fetch as much as fifty shillings 
per lb., but the inferior nests contain many impurities, 
and are perhaps worth not more than two shillings. This 
curious article of commerce is produced by a small swift 
of the genus Collocalia (C. linchi and others), and is used 
by rich Chinese for making soup. Although a few nests 
are sometimes seen built against the sea-cliffs in the full 
glare of the sun, the vast majority occur in caves in the 
limestone rock, and are often in complete darkness. In 
such places the birds build in incredible numbers. Thus, 
the yield from the Gomanton caves is valued at over 
£5000 annually. The collecting is chiefly carried out 
by Buludupi Dyaks, who show the most extraordinary 
skill and daring, obtaining the nests even from the roofs 
of the caves, which are sometimes three or four hundred 
feet or more in height. Long bamboos with a candle 
affixed near the end are used for detaching the lower 
nests. To obtain the others slender rattan ladders are 
pegged against the walls, and skeleton stages of bamboo 
run out in what appear to be utterly inaccessible situations. 
When it is remembered that the work is carried on 
almost in darkness and at such dizzy heights, it is only 
remarkable that there are not more fatal accidents than 
