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 makes a long fall "hard." The earth is struck with greater force. The gain in speed would be multiplied many times each second, instead of being added to at the rate of just thirty-—two feet, if it were not for the resistance, or pushing back of the air. The air is a cushion. If it wasn’t for the air raindrops, and especially hard hailstones, would hit us with the force of bullets.

ARE THE STARS INHABITED?
When you look up at the stars at night don't you wonder if people like ourselves live upon any of them? Some of the stars we know are far away suns, much larger than the sun that lights and warms our earth. A few of them are planets that, like the earth, circle around our own sun. If you were on one of these planets the earth would appear to you as one of the stars in the sky. We cannot really know if people live on the other planets. But we can think of all the reasons why we are able to live on the earth. We have light and heat from the sun, air to breathe, water to drink and to make plants grow. The plants and animals and minerals on the earth are suited to our needs for food and clothing and shelter. If anyone or all of these things differed from what they are we, too, would have to be different, or we could not live here. So if people exactly like ourselves are living on any other world, that world would have to be very much like the earth. Astronomers have not found any other planet that is just like our earth in these things that are so necessary to people made as we are.

The question as to whether there is animal life at all on other worlds, is quite different. On this earth of ours are thousands of varieties of living creatures. They can live in the deepest sea, on the highest mountains, in the coldest and the hottest countries, and on many kinds of food. It would be very strange, among so many worlds, if ours was the only one that would support life. We do know that other worlds are made of the same elements as our own. They have lime and iron and salt and hydrogen, and other things in them that are necessary to life. On our earth, plant and animal life have been developed and fed out of these elements. So it seems only reasonable that where these are present living creatures should be able to exist. On the little red planet Mars, that is nearest us and that we can best study, we have many reasons for thinking that intelligent beings do live. But for many reasons they must be different from us. Mars is smaller than our earth and older. It is