It was not until the Industrial Revolution in the first half of the 19th century that book printing changed radically. The metal press perfected by Didot in 1783 and the steam-powered system invented in 1807 replaced hand-operated machines. Paper was produced in rolls and no longer sheet by sheet. Ink rollers were introduced in 1819 and flat-bed cylinder presses in 1812. In 1847, the invention of the high-speed rotary press revolutionized the 19th-century printing industry. Operating mechanical presses had become a highly specialized job.
The first modern printing press was built in Philadelphia in 1846. It printed 95,000 copies an hour – no comparison with the 300 copies printed daily on the hand-operated machines three quarters of a century earlier! The race, which had begun with the rotary press, gained momentum with Megenthaler’s invention of linotype in 1887. With this new technique it was possible to compose entire lines at a time, instead of setting texts letter by letter. In other words, 6,000 to 9,000 characters an hour were set, compared with 1,000 to 1,500 previously.
In the mid-20th century, photocomposition, a method of composing text by photographing characters on film, further revolutionized printing.
Nowadays books are a small fraction of all printed matter (newspapers, magazines, brochures…). But it is globalisation and multimedia, with the advent of electronics and new means of controlling space and time, typical of the information society of the late 20th century, that have introduced a radical change in the production, dissemination and delivery of the written word. The constraints inherent in books have disappeared. There are now ways of consulting documents on CD-Roms and the Internet by browsing and creating hyperlinks. Remote transmission and access to a growing number of networks and databases provides endless possibilities of interacting and modifying texts online.