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Many interesting attempts were made to fly in the air. Men fixed wings onto themselves and jumped from high places. But again and again these attempts failed. Then man made balloons filled with gases lighter than air. But these could not be steered; they went only where the wind carried them. Then when petrol engine was invented the first aeroplane was made. Since then traveling by air has much improved. Aeroplanes have now become much bigger, stronger, faster and safer. Today, new kinds of planes are in use. We have the helicopter, which can rise straight up from the ground, and the jet plane, which travels faster than sound.
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