The earliest documents were written on clay tablets, and then on parchment, made from the skin of sheep or goat, or vellum, made from calf skin. A writing material made from the stem of the papyrus plant was also known to the ancients. These material were however quite inadequate for the huge volume of printedmatter that was made possible by Guetenberg`s inventions.
The answer was paper invented by the Chinese nearly 200 years ago, but not widely known in Europe until the 12th century. Paper can be made from virtually any fibrous material. The commonest in use today is wood pulp, but recycled material such as rags or waste paper are also used.
After felling, trees are turned into chips and then digested into pulp using sodium sulphate. The pulp is bleached and then flows through a narrow slit on to a moving screen that allows the water to drain away. The paper is then pressed to remove more water and dried by steam heated cylinders. Finally the paper is treated with pigments such as clay to give it a smoother finish, or given a glossy surface with chalk or titanium dioxi