The Linotype machines were the second revolution in the graphic arts
When Gutenberg in Mainz manufactured the first types of phones in Europe (there are samples in the Gutenberg Museum of Chinese movable type very prior to the development of these in Europe) there was a revolution in the process of creation of books, I step of copying books by hand one by one to be able to compose pages that could be repeated in a way mechanics lack the time to do.
In the year 1886 Ottmar Mergenthaler He invented the Linotype and the second revolution was generated in the production of books, so far the composition of pages manually placing types hand in a "mediator" to form a line and character to character form a page, with his invention Ottmar Mergenthaler allowed the composition of complete lines in a mechanical way with an increase of speed in the production of pages huge in comparison with manual composition.
Linotype was the largest company in the manufacture of equipment for the production of books for years, until digital system stormed the market, but that's another story...
About Linotype has shot even a documentary that shows how they worked these amazing machines.