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 sources of supply are the wastes of other industries, and wastes which have no other uses.

The classification may take place as follows: (a) waste—rags, sails, sacking, ropes, textile wastes, waste paper; (b) plant stems and wood—straw, esparto, bamboo, papyrus, hedychium; (c) pulps or half-stuffs—straw, esparto, delta cellulose (or reed pulp), bamboo, chemical wood, mechanical wood.

Rags are the cast-off fabrics of the civilised world. Having served their purpose in administering to the comfort of mankind, they are sorted, graded, and offered in the market for papermakers. For the manufacture of paper for bank-notes new linen cuttings are used, but this is an exceptional material for a special purpose. Sail cloth, bagging, sacking and ropes, made from hemp, jute, manilla hemp, having reached the waste market, are regenerated in the mill as paper. Waste paper of all kinds is sorted and re-made into paper or boards.

Esparto is the principal material that finds its way to the papermaker in its original state. It is a wiry grass, growing extensively in Spain and Africa, and is harvested and packed in bales for export. Straw is generally imported as half-stuff. Bamboo, papyrus, and hedychium are being used in quite a small way in this country, but may be extensively used in the future.

Straw, esparto, reed pulp, and bamboo are obtainable as half-stuff or pulp, that is, they are already divested of the portions of the plant which are non-fibrous, and therefore useless to the papermaker. Wood pulp is the chief material converted into paper, and may be prepared as chemical or mechanical. Chemical wood pulp is prepared, after removing the bark from the felled trees, and cutting the logs into chips, by boiling with caustic soda solution (soda pulp), with a mixture