How is Milton's description of birds realistic? Meanwhile the tepid Caves, and Fens and shores
Their Brood as numerous hatch from th' Egg that soon
Bursting with kindly38 rupture forth disclos'd
Their callow39 young, but feather'd soon and fledge40 420
They summ'd their Pens41 and soaring th' air sublime
With clang despis'd the ground, under a cloud
In prospect; there the Eagle and the Stork
On Cliffs and Cedar tops their Eyries42 build
Part loosely wing the Region, part more wise 425
In common, rang'd in figure wedge their way,
Intelligent of seasons, and set forth
Their Aery Caravan high over Seas
Flying, and over Lands with mutual wing
Easing their flight; so steers the prudent Crane 430
Her annual Voyage, borne on Winds; the Air
Floats,43 as they pass, fann'd with unnumber'd plumes:
From Branch to Branch the smaller Birds with song
Solaced the Woods, and spread their painted wings
Till Ev'n, nor then the solemn Nightingale 435