"So the Bluebirds have contracted, have they, for a house? And a nest is under way for little Mr. Wren?" "Hush, dear, hush! Be quiet, dear! quiet as a mouse. These are weighty secrets, and we must whisper them." Susan Coolidge. * * * * * CHAPTER III THE BIRD BABIES Today, Violet, I shall tell you another secret, but this time the secret is not about flowers, but about something else we love very dearly. I intend to tell you some secrets about the birds. I wonder if you know how much they are like the flowers? You remember, the flowers had a language which we could understand, even if they did not talk out loud. The birds, too, have a language of their own, and they can express themselves better than the flowers, for they have a sign language, and are also able to make sounds. How much we enjoy hearing the birds sing, not only because they make beautiful music, but because they are telling us how happy they are! If birds are in pain or in trouble, their notes are quite different from when they are singing; while, if they or their little ones are in danger, they quickly send forth a note of warning. The young birds, in calling for food, make an entirely different sound, and the answer of the mother bird is a sweet lullaby. One of the ways birds express themselves in sign language is by their feathers. If they are sick, their feathers droop. When they are well and happy, their feathers seem much brighter. In the bird family, as in the flower family, each member has a special work to do. The mother bird and the father bird work together to build the nest, but while the mother bird lays the eggs and then must sit on them for a number of days, the father bird must bring her food and water and sometimes take his turn watching the nest while the mother goes for a little exercise. The mother bird's body resembles the plant, too, for it needs fresh air, food and water. Instead of leaves to take in the air it has lungs, which not only take in the fresh air but also send out the impure air. Instead of the little rootlets to take in the food and water from the ground, the bird has a mouth, and as the bird is not fastened to the ground, but is free to fly or move about, it goes after its food. Instead of sap, it has blood to carry the food to all parts of the body. The birds have ovaries just the same as the flowers, and inside each ovary are a number of little seeds or ovules which by and by will grow into birdies. It takes quite a while for the ovules to ripen, just as it took quite a while for the seeds to ripen, and when they are ripe they must have a nest prepared for them, just as the flowers did. But the birds are not as helpless as the flowers, and are able to make their own nests. So when the ovules (which are called eggs when they are ripe) are ready, the parent birds select a nice place for a home.