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Introduction Balls have been toys practically forever, but the bouncing ball is a more recent innovation. Bouncing balls were originally made of natural rubber, though now bouncing balls can be made of plastics and other polymers or even treated leather.
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The principle is simple and seductively clever: solar lights that store energy during the day and release light at night. These can be purchased ready-made in a variety of colors (yellow, blue and red) but they can also be built at home . A simple, less-technical approach involves buying a conventional solar-powered yard lamp and then essentially harvesting it for key pieces to put in a jar.