UNTIL a little more than one hundred years ago, the chief power used in the production of food, clothing, and shelter was hand power. Cattle and horses were used to cultivate the fields. Windmills and water wheels were employed to grind corn and wheat. But most tools and machines were worked by hand.
THIS book contains twelve stories of great inventions, with a concluding chapter on famous inventors of today. Each of the inventions described has added to the comforts and joys of the world. Each of these inventions has brought about new industries in which many men and women have...
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