104 THE ARCHITECTURE OF BIRDS. 
shipping is 30,000 tuns. In the Archipelago, at the 
prices already quoted, this property is worth 1,263,519 
Spanish dollars, or 284,290/. The value of this 
immense property to the country which produees it, 
rests upon the capricious wants of a single people. 
The value of the labour expended in bringing birds’ 
nests to market is but a trifling portion of their price, 
which consists of the highest price which the luxu- 
rious Chinese will afford to pay for them, and which 
is a tax paid by that nation to the inhabitants of the 
Indian islands. There is, perhaps, no production 
upon which human industry is exerted, of which the 
cost of production bears.so small a proportion to the - 
market price.”* 
Auruovuen we have considered birds as miners, as. 
ground-builders, as masons, as carpenters, as plat- 
form-builders, as basket-makers, as weavers, as tai- 
lors, as felt-makers, and as cementers, we have not 
dwelt at much length upon any fancied analogies 
between their arts and those of the human race. 
The great distinction between man and the inferior 
animals is that the one learns almost every art pro- 
gressively, by his own experience operating with the 
accumulated knowledge of past generations, while 
the others work by a fixed rule, improving very 
little, if any, during the course of their own lives, 
and rarely deviating to-day from the plans pursued 
by the same species a thousand years ago. It is 
true that the swallow, which doubtless once built its 
nest in hollow trees, has now accommodated itself 
to the progress of human society by ehoosing chim- 
neys for nestling; and it is also to be noticed that, 
in the selection of materials, a great many birds, as 
we have already shown, accommodate themselves 
* Crawfurd’s Indian Archipelago, val. iii, 
