At age 100, how the national parks grant 'breathing space'

One hundred years ago today, President Woodrow Wilson signed the Organic Act, creating the National Park Service. To reflect, Jeffrey Brown takes his Bookshelf segment outdoors to Virginia's Great Falls Park. He's joined by Terry Tempest Williams to discuss her new book, which narrates the stories of America's "sacred lands," the power they offer visitors and the challenges of maintaining them.