Phil Pressel designed cameras for the government's top-secret Hexagon project. He's only recently been able to speak about his life's work.

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Creek geologists Janet Sowers and Christopher Richard stand next to a plaque that puts a lagoon in San Francisco's Mission District.

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It took 14 years for stone carvers to create the Mount Rushmore monument, seen here in 1995. Gloria Del Bianco's father, Luigi, led the carving team.

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John Brown's Last Stand: After the raid, John Brown's Fort — part of the U.S. Armory and Arsenal at Harpers Ferry — became the town's only armory building to survive the Civil War.

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