Keywords: PSM V51 D227 Charles Henry Hitchcock.png Photographic portrait of United States geologist Charles Henry Hitchcock http //www archive org/details/popularsciencemo51newy Popular Science Monthly Volume 51 1897 author PD-old Extracted image from book to grayscale cropped whitespace ineuw http //www archive org/details/popularsciencemo51newy Popular Science Monthly Volume 51 Popular Science Monthly illustrations/Volume 51 Charles Henry Hitchcock Black and white photographic portraits of men Hitchcock Charles Henry |