In California’s Death Valley National Park in 1915, a prospector named Joseph Crook visited the dried lake-bed of Racetrack Playa and stumbled upon scores of boulders that had apparently moved across the surface, leaving very obvious trails. With...
In California’s Death Valley National Park in 1915, a prospector named Joseph Crook visited the dried lake-bed of Racetrack Playa and stumbled upon scores of boulders that had apparently moved across the surface, leaving very obvious trails. With...