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A list of Benjamin Franklin's inventions reveals a man of many talents and interests. It was the scientist in Ben that brought out the inventor. His natural curiosity about things and the way they work made him try to find ways to make them work better. Ben had poor vision and needed glasses to read. He got tired of constantly taking them off and putting them back on, so he decided to figure out a way to make his glasses let him see both near and far. He had two pairs of spectacles cut in half and put half of each lens in a single frame. Today, we call them bifocals.