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A balloon is conceptually the simplest of all flying machines. The balloon is a fabric envelope filled with a gas that is lighter than the surrounding atmosphere. As the entire balloon is
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![A balloon is conceptually the simplest of all flying machines. The balloon is a fabric envelope filled with a gas that is lighter than the surrounding atmosphere. As the entire balloon is A balloon is conceptually the simplest of all flying machines. The balloon is a fabric envelope filled with a gas that is lighter than the surrounding atmosphere. As the entire balloon is](https://c8.alamy.com/comp/2B033DK/a-balloon-is-conceptually-the-simplest-of-all-flying-machines-the-balloon-is-a-fabric-envelope-filled-with-a-gas-that-is-lighter-than-the-surrounding-atmosphere-as-the-entire-balloon-is-less-dense-than-its-surroundings-it-rises-taking-along-with-it-a-basket-attached-underneath-which-carries-passengers-or-payload-although-a-balloon-has-no-propulsion-system-a-degree-of-directional-control-is-possible-through-making-the-balloon-rise-or-sink-in-altitude-to-find-favorable-wind-directions-2B033DK.jpg)
A balloon is conceptually the simplest of all flying machines. The balloon is a fabric envelope filled with a gas that is lighter than the surrounding atmosphere. As the entire balloon is
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A balloon is conceptually the simplest of all flying machines. The balloon is a fabric envelope filled with a gas that is lighter than the surrounding atmosphere. As the entire balloon is
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