Popular Patents is a fascinating look at more than 80 inventions with detailed information about each invention's historical evolution, a biographical sketch of the inventor, and a brief description of how the invention was made. The introduction contains brief histories of U.S. patent laws, U.S. Patent and Trademark Office, and U.S. patent models. The book contains entries to over 80 inventions including: air conditioning, anesthetic, barbed wire, billiard ball, carpet loom, color film, condensed milk, diesel engine, dirigible, frozen food, halftone printing plate, jet engine, Linotype, machine gun, motion pictures, phonograph records, revolver, smokeless gunpowder, submarine, telegraph, television, triode vacuum tube, typewriter, vulcanized ribber, xerography, and zipper. The book has incorporated within the text either a copy of the patent drawing or the first page of the patent for each of the above inventions. It concludes with a bibliography and an index.