"And my hand hath found, as a nest, the riches of the people; and as one gathereth eggs that are left, have I gathered all the earth; and there was none that moved the whip, or opened the mouth, or peeped."—Isaiah x.
1051. Why do all birds lay eggs?
Because, to bear their young in any other manner, would encumber the body, and materially interfere with their powers of flight.
As soon as an egg becomes large and heavy enough to be cumbersome to the bird, it is removed from the body. A shell, impervious to air, protects the germ of life within, until from two to twenty eggs have accumulated, and then, although laid at different intervals, their incubation commences together, and the young birds are hatched at the same time.
CHAPTER LIII.
1052. Why have birds with long legs short tails?
Because the tails of birds are used to guide them through the air, by a kind of steerage. When birds with long legs take to flight, they throw their legs behind, and they then serve the same purpose as a tail.