PAPER FIBRE PLANTS. 139 



Roussa Grass (Andropogon Martini^ Gramirieoe). This is one of a 

 number of Indian grasses belonging to this genus, the fibres of which 

 have been used for paper-making. 



Neamur grass oil is also extracted from this species. 



Tussock Grass or Mat Grass (Xerotes longifolia, Juncacese). This 

 plant is a native of Australia, and belongs to the Rush family. The 

 name Xerotes has been given to it on account of the aridity of the 

 situation in which the plant grows, viz., a dry, open, and sandy country. 



The leaves are considered a good substitute for Esparto grass. They 

 are linear in form and of a leathery texture, but toothed at the apex and 

 margins. The shoot or culm of this plant has been used for making 

 baskets by the Yarra tribe, South Eastern Australia. Specimens are 

 shown in No. 2 Museum of the Royal Gardens, Kew. 



Wood Pulp. This is rather confused and mixed up with paper- 

 making. Wood pulp is prepared from Spruce Fir and Pine trees growing 

 in Norway, Sweden, and America. The trees are cut down and deprived 

 of their bark as much as possible, the ultimate cleanness of the pulp 

 depending on the completeness with which this is carried out. They are 

 next cut up into logs of a suitable size and the knots taken out, after 

 which they are immersed in a liming solution. 



There are two methods of manufacturing wood pulp; the one 

 mechanical, applied to spruce (Abies) and pine (Pinus) : the other 

 chemical, in which all kinds of wood are used. 



The mechanical process of wood-pulp manufacture consists in grind- 

 ing the wood under water into pulp by edge runners, followed by treat- 

 ment in a beating engine, the water abstracting most of the soluble 

 impurities of the woody fibre, such as its gummy and gelatinous parts. 

 Then the pulp is put through a kind of paper-making machine, and after 

 undergoing a process of bleaching, is made into sheets. 



The chemical process used in preparing wood pulp consists in boiling 

 the wood, previously broken up into small pieces, with soda, sodium 

 sulphite or sodium sulphate, whereby the impurities in the wood are 

 more completely eliminated and a finer kind of pulp obtained. Chemical 

 wood pulp is known in the trade as soda pulp or sulphite pulp or sulphate 

 pulp. 



The first is generally of a brownish colour, and is used for making 

 brown papers. The sulphite pulp is of a good white colour, and is con- 

 sidered the best of the wood pulps. Sulphate pulp is rather darker in 

 colour than sulphite pulp ; it is only made in small quantities. After 

 boiling with chemicals, the wood is made into a pulp by treatment in a 

 grinding mill and beater, and then it is made into thin sheets in an 

 ordinary paper-making machine. 



