Chester Carlson Invents Machine To Copy Documents
The model department of the United States Patent Office in Washington is illuminated here and there with the original models of the very great...
Charles Babbage Invents Mechanical Calculator
The model department of the United States Patent Office in Washington is illuminated here and there with the original models of the very great...
English Gentleman Invents Photography
The model department of the United States Patent Office in Washington is illuminated here and there with the original models of the very great...
Professor W.C. Röntgen Discovers X-Rays
The model department of the United States Patent Office in Washington is illuminated here and there with the original models of the very great...
Ferry Boatman Challenges Steamboat Monopoly
The model department of the United States Patent Office in Washington is illuminated here and there with the original models of the very great...
Printer Invents Typewriting Machine
The model department of the United States Patent Office in Washington is illuminated here and there with the original models of the very great...
