554 AUXILIARY FOREST INDUSTRIES. 



even boats, hollow beams for huts, underground tubes for 

 telephone wires, frames for doors and windows, oars, etc. 

 The spokes of railway-carriage wheels are replaced by fill- 

 ings with compressed cellulose. Antiseptic wood-cellulose of 

 silver-fir is used for binding wounds. Cellulose is used for 

 floor-cloth and oil-cloth, for packing material specially used 

 for the despatch of gunpowder, and for many other purposes. 

 It is also used for insulating electric conductors, and experi- 

 ments have been made to prepare gun-cotton from cellulose. 

 Silk is also made from cellulose. 



Chardonnel and Lehnert have a patent for converting 

 sulphite-cellulose made of 'sprucewood into nitrocellulose by 

 treating it with nitric acid. It then resembles collodion and 

 is drawn through fine glass tubes, which press it into 

 extremely fine threads ; 12 to 14 of these threads are 

 spun into a silk thread. The danger of an explosion is 

 avoided by denitrifying the collodion. This artificial silk is 

 even more lustrous than natural silk and can be dyed readily. 

 Most of the cheap silk goods now in the market are made of 

 artificial silk. 



A watery solution of cellulose in combination with soda and 

 carbon-bisulphide is named viscose and used as a substitute 

 for glue ; when this is heated a hard amorphous substance is 

 produced, viscoid, which in various colours is used instead of 

 costly celluloid. True celluloid is produced by heating and 

 pressing nitro-cellulose and camphor ; this transparent sub- 

 stance is used as a substitute for tortoise-shell, ivory, 

 caoutchouc, etc., or for counterfeiting these substances. 

 Celluloid may be rendered uninflammable, and is then called 

 pegamoid. 



(b) Sugar and Alcohol. As cellulose has the same 

 chemical composition as starch it has been proposed to manu- 

 facture from it sugar and alcohol. The wood in small pieces, 

 wood-pulp or sawdust, is acted on by acids and boiled for 

 some time under pressure in order to convert it into sugar 

 and by means of diastase to ferment it into alcohol. Although 

 no successful results are known to have been obtained, it 

 appears as if a great transformation in the manufacture 

 of alcohol will result and that inferior wood-assortments 



