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52 fibre as is consistent with the necessary cohesion, but of course manufacturers prefer to keep special methods to themselves. At the paper machine little or no shake is given, and very light pressure is given throughout, just sufficient to smooth the paper down. Strength is not aimed at, but the paper must be strong enough to resist the handling it will receive in ordinary use.

Most blotting papers are made in demy, with a standard weight of 38 Ib. per ream of 480 sheets. There are blottings made of wood pulp, but these are far below the rag papers in efficiency. Soda wood pulp makes a very fair blotting paper, but sulphite wood is not so absorbent as soda pulp paper. Wood pulp blottings are usually made in thin substances for interleaving diaries and similar books, where repeated use will not be required. Enamelled blotting papers are made by pasting enamelled (coated) papers to the ordinary blotting paper and rolling down. These blottings can be obtained in a variety of colours, both the blotting and surface paper being varied in colour. Coloured blottings are made of the usual ingredients, with added colouring matter.

Duplicating, impression, and multi-copying are different names for the same papers. They are used for the various duplicating machines of the cyclostyle and mimeograph patterns, where a number of copies of written or typewritten matter is required quickly. A very thin ink is used, and it is necessary that it should be absorbed very speedily. These papers are practically unsized, contain a large proportion of esparto for the better qualities, and a certain quantity of mechanical wood in the cheaper sorts. A very large range of these papers is obtainable: laid or wove, white, cream or tinted, with rough or moderately smooth finish. For copies produced by the same process, where