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 known it, there are big shadows that puzzle grown up people. Everything in the world has a shadow that follows it, even our big earth and the moon. Sometimes we can see the shadows of the earth and the moon.

It is Just like this. Did your papa ever make shadow rabbits on a wall? He lifted his folded hands between the lamp light and a wall, so that a shadow of them was thrown on the wall. Then, with his fingers and thumbs, he made a little rabbit's snub nose and twitching ears. A shadow is the same shape as the solid object that makes it. It is made only when the object gets between a bright light and a screen upon which the shadow can be thrown. Your body makes a shadow on the earth when you get between the sun's light and the earth. When the moon gets between us and the sun, the moon's shadow is thrown on the earth. That is a big, beautiful shadow! The moon hides the sun, and throws its own shadow over the half of the earth the sun happens to be shining on. The hiding of the sun is called an eclipse; the effect of it is a vast shadow on the earth that makes our sky as dark as night. You know it is always cooler in the shade or shadow of a house or tree than in the sun. In this enormous shadow of the moon the earth grows colder. Dew is formed. Flowers close their cups. Surprised chickens go to roost at midday.

There is an eclipse of the sun by the moon once a year, but most years the eclipse is only partial, and we see it only if it happens in our daytime. There is an eclipse, or hiding of the moon, once in the every twenty-eight days that it takes the moon to go around the earth. just once, on the journey, the earth gets between the sun and the moon. Then the earth's shadow is thrown on the moon. The eclipse of the moon, too, is very seldom complete, and we do not see it at its best unless it happens at night, and when the moon is full and the sky clear. You can watch the earth’s shadow pass over the moon in a total eclipse with the naked eyes. But for an eclipse of the sun you will need smoked glass or blue or gray spectacles, for all around the black, hidden center of the sun, there will appear a dazzling corona, or crown, of the sun’s thick envelope of burning gases and far-thrown light rays.

WHY DOES A BEE HUM?
Hm! Hm! Let’s see. A bee isn’t the only thing that hums. A wheel, turning r rapidly, whirs. A teakettle "sings" when the water boils. A violin string quivers with a musical note that slowly