A sheet of paper consists of vegetable fibers of different sizes, twisted and intertwined with each other and finally squeezed together to make a sheet with a surface smooth enough to write or print on.
Originally it was discovered that if a mixture of wood pulp and water was spread on a sieve, the water would drain away and leave a deposit which, when dry, could be peeled off as a sheet of paper.
Although the Chinese had been using paper since A.D. 105 it was not introduced into Europe until the 15th century. The raw materials used for modern hand-made paper are cotton and linen rags. Such paper is very expensive to produce.
Machine-made paper is processed in paper mills from esparto grass, wood and straw, and is much cheaper. The materials for both types of paper-making have to be put through the same basic procedure of repeated washing and bleaching to get rid of impurities.
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