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repeatedly against the surface of the water, until the impuri- 

 ties are washed out. After exposing the fibres for 2 or 3 days 

 in the sun they should be tied in bales and got ready for 

 sale. 



430. The cost of cultivation inclusive of manure comes to 

 about Rs. 30 per acre. The outturn when so much money is 

 spent, ought to come to 15 maunds per acre, which at Rs. 4 

 per maund, would bring a net profit of Rs. 30 per acre. 



Chemistry of jute. Jute may be called a ligno-cellulose, 

 standing midway between cotton which is almost pure 

 cellulose and lignose of woody fibre. Good qualities of jute 

 have the following composition : 



per cent. 



431. The proportion of cellulose in jute is much less than 

 in cotton. In fact, jute-fibre when young is richer in cellulose 

 but gradually by loss of water and CO2 cellulose becomes partly 

 converted into lignose. Like cotton, jute can be dissolved by 

 a concentrated solution of zinc chloride by a mixture of zinc 

 chloride and hydrochloric acid. By dilution and acidification 

 of these solutions, the fibre is precipitated as a gelatinous 

 hydrate to the extent of 75 to 80 per cent, of the original fibre 

 when the solution is fresh. It is important to distinguish 

 between jute and cotton as jute cloths are now commonly 

 sold in the market. Chlorine combines readily with jute, the 

 latter taking up 15 to 16 per cent, of this element. If the 

 Chlorinated fibre be treated with a solution of Sodium 

 Sulphite, a Magenta red colour is obtained, which is char- 

 acteristic only of jute fibre. To distinguish jute from flax 

 and hemp, an aqueous solution of iodine should be used. 

 Jute is coloured deep brown, while flax and hemp are 

 coloured blue or violet. Jute absorbs acids and alkalis from 



