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material may be used for making into paper it has to undergo stages of preparation which can be divided into removing all foreign matter and dirt, reduction to fibrous state, bleaching, beating, and lastly converting what is the pulp into paper. If the material has already been manufactured, as in the case of rags, ropes, sails, sacking, and other textiles, the first process is somewhat simpler than in the case of really raw materials, such as esparto, bamboo, or wood. But here again the first and second operations may have been carried out before the papermaker handles the material, for wood, esparto, and bamboo are imported as pulp boards. In the case of esparto the quantity so imported is very small, but the quantity of wood pulp is enormous. It will be advisable to take the materials in order, so that the difference as well as the similarity of treatment may be traced.

Rags are purchased already graded. There are some twenty to thirty grades of rags regularly quoted in the market reports, and the layman might fancy that the papermaker could unpack the bales and proceed to make paper from these graded rags. Unfortunately he finds a large quantity of undesirable material, such as silk, wool, buttons, elastic, and dirt, that must be removed. First the rags are sorted, and cut into pieces of uniform size, the undesirable parts mentioned