The blind may soon have an electrical gadget to help them get around without bumping into obstacles. The basic idea, now being worked on by the Army Signal Corps, is a small box shooting out a narrow beam of light. By turning the beam from side to side, the blind man can feel his way. When the beam hits a lamppost, a fence or any such obstacle, its light reflects back to a lens and is focused on a photoelectric cell. A gentle buzz in an earphone warns him that the obstacle is near....
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