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 on tl1e other side, and it couldn't shine through the solid earth, now, could it?

Turn the orange-earth over and over, slowly, on the hatpin. That is the way the earth turns. The sun is always shining on one-half of it, but the light half is constantly changing. As the earth always turns eastward toward the sun, the sun seems to travel westward. It takes just one day, or twenty-four hours, for the earth to turn over once, and give all parts day and night. So, when it is noon in the United States the little Chinese boys and girls on the dark side of the earth are fast asleep. And when they are hurrying to school very likely we are undressing to go to bed.

This is a little harder to understand. Perhaps you don't know that the date does change—but if it didn't, then when it is Sunday on one side of the earth it would be Monday on the other.

Turn your orange-earth over slowly and watch the light rays strike one side after another. Remember, day is always beginning somewhere. It is always noon somewhere, always night, and it takes twenty-four hours for any one spot on the earth to go through all the changes of morning, noon, evening, midnight.

Since this is true, the people of the great trading nations had to agree on a place where a new day should begin for everybody. You see they needed to date letters and telegrams, newspapers and business papers of all sorts. It wouldn't do to have a date-changing line pass through a big city, or even through a country where many people lived. For it would make no end of trouble to say it was Monday on the west side of a busy street, and Tuesday on the east side. A place was chosen to run a date line north and south, away out in the middle of the Pacific Ocean. Cut a line on the skin of the orange-earth from where the hatpin goes in, at one end, to where it goes out at the other. We’ll call that the date line; although, as a matter of fact, the real dateline is not straight up and down, but zigzags about among islands. It goes half way around the earth, up and down the very widest ocean. Now continue the line around, dividing the earth into two halves. On the line exactly opposite the date line stands London, the greatest trading and banking city on earth, with 6,000,000 people living in it. There, time and dates are very important, so the trading nations agreed to keep London time—that is, to date everything