216 MISCELLANEOUS FIBRES 



into pulp, and the quality of the product, including the 

 length, strength and felting capacity of the fibres, 

 and the colour of the pulp and the ease with which it 

 can be bleached. 



The chief fibres at present employed in the paper 

 industry are cotton., flax, hemp, jute, Manila hemp 

 and other cordage fibres, wood pulp, esparto, and 

 straw. 



In the case of cotton, the raw material consists 

 mainly of rags and waste from the spinning mills ; 

 during recent years the " fuzz " or short fibre on the 

 husk of the cotton seed has also been employed. Flax 

 is used in the form of linen rags, spinning waste, 

 and scutching refuse. The hemp employed consists 

 similarly of spinning waste, scutching refuse and old 

 cordage. Ramie waste is sometimes used for special 

 kinds of paper to which it imparts considerable 

 tenacity. Jute waste of several kinds is used, such 

 as the butts or root-ends (page 138), waste from the 

 textile factories, and old sacking. Manila hemp and 

 other rope-making fibres (such as Sisal hemp and New 

 Zealand hemp) reach the paper-mills chiefly in the 

 form of old ropes ; these are disintegrated by 

 machinery and treated with caustic soda or lime. 

 Manila hemp furnishes strong, tough papers. 



Wood Pulp. Enormous quantities of wood are 

 now employed for conversion into wood pulp for 

 paper-making. The soft, coniferous woods, such as 

 the various kinds of fir, pine and spruce are used in 

 Scandinavia and Canada, whilst poplar and timber 

 of certain other dicotyledonous trees are employed in 

 the United States and certain parts of Europe. 



Wood pulp is of two kinds, mechanical and chemical. 

 In the manufacture of mechanical wood pulp, the 

 trees after being felled are sawn into blocks about 

 2 feet long. The bark is then removed and the wood 

 is ground by forcing the blocks by hydraulic pressure 

 against rapidly revolving grindstones over which a 

 continuous stream of water is caused to run. The 

 ground wood is carried by the water into a pit below 

 the grinder and the coarser pieces are removed by 

 passing it through a series of strainers. The pulp is 



