10 INTRODUCTION. 
fish in the brook, along the margin of which a fam. 
ily of sandpipers were hunting down aquatic insects 
while some swallows which skimmed along on the 
wing were ready to dart upon the flies which es- 
caped from these swiftfooted pedestrians; he saw 
bank-swallows burrowing in the bank to shelter 
their nests from bad weather and worse enemies; he 
saw a heron take her patient stand at a bend of the 
river to watch for a passing fish, and, after a suc- 
cessful capture, fly off with her prey to her nest in 
the woods; and he saw a troop of starlings as nu- 
merous as a swarm of bees; the same phenome- 
non which nearly three thousand years before had 
afforded Homer a fine poetical simile for a troop 
of fugitive warriors. ‘So it is,” the narrative con- 
cludes ; ‘one man walks through the world with 
his eyes open, and another with them shut; and 
upon this difference depends all the superiority of 
knowledge the one acquires above the other.” 
There are few persons, even of the well-informed, 
who, like the schoolboy with “his eyes open,” 
take an interest in such common occurrences as 4 
wheatear hopping over stones, or a swallow hawk- 
ing for flies over a brook. A taste for natural ob- 
jects must be awakened and cultivated before en- 
joyment can be derived from the casual observation 
(if study be a term too strong and repulsive) of the 
works of creation, either in their picturesque and 
poetical aspects, or in their beautiful adaptation to 
their various purposes. But when an interest in 
natural productions has been once excited, we may 
confidently promise that the sources of pleasure will 
become exhaustless, and every walk, however short, 
will produce, like the ramble of the curious school- 
boy, something which has not been observed be- 
fore. 
When Alexander Wilson, the celebrated writer 
on the Birds of the United States, commenced his 
arduous task of examining every bird of that country 
