verhead huge bats flitted round us, while on every side the tiny
chirp of innumerable birds was taken up and echoed from seemingly a
thousand voices throughout the cavern. Above the head of the Chinese
appeared a number of nests, something in the shape of large deep spoons
without handles, split in half longitudinally, smaller than the ordinary
swallow's nest. They were placed, without any order apparently, on
every spot where a slight projection of the rock afforded a foundation.
The Chinese, like their friends on board the junk, began to abuse us for
coming to interfere with their occupation. Mr Hooker, however, soon
pacified them, and offered them some money for a few of the nests, that
we might examine them. This brought them at once into good humour, and
they very readily sold us a dozen or more of the nests, though I thought
the price for birds' nests a very high one. A number of birds like
swallows were flying in and out of the cavern. They had the flight of
swallows; indeed, Mr Hooker said they were a species of swallow. They
were about the size of robins or sparrows; their breasts white, their
wings grey, and their backs and the feathers of their tails shining
black. On examining the nests which we had purchased, we found that
they were composed of a gelatinous substance something like isinglass.

"This is the substance," Mr Hooker told us, "that the Chinese make into
broth. They are packed, however, just as they are cut from the rock,
and carried to China. There they are cleansed from all extraneous
substances, and are then boiled or stewed, every particle of dirt being
thus more completely removed; and then, with a mixture of spices, they
make a transparent, delicate-looking jelly, although, without the
spices, they have little or no flavour."

"But where can they obtain this jelly-like substance?" asked Emily.

"I believe it is produced from a mollusc of some sort, on which the
birds feed. When they require to build their nests, they disgorge the
gelatinous portion for the purpose; and as this substance possesses the
nutritive qualities of animal matter, I have little doubt that it is
produced from these molluscs," said Mr Hooker.

Not only within the cavern, but on all available and tolerably sheltered
spots outside, we saw a number of the sea-swallows' nests. We pulled
close under one cliff, where we could distinguish clearly a bird sitting
in its nest--we concluded on its eggs--and looking v