. . "Photographs" . . . . . . . . . "Engravings" . "Illustrations" . . . "Sindeband collected letters and documents of scientists and inventors, many of them with eponymous names, such as: Andre Ampere, Marie Curie, Wilhelm Rontgen, Alessandro Volta, and James Watt." . . . "Translations" . . . . . . "Articles" . . . . "Diagrams" . . . "Portraits" . "Patents" . . . . .