104 CORDAGE FIBRES 



hydrochloric acid, and ammonia. Untwist the cord or unpick 

 the fabric and untwist the threads so that the fibres separate 

 one from the other. Place the threads thus prepared in a 

 saucer, sprinkle and saturate with the chloride of lime solu- 

 tion. A few drops of hydrochloric acid are then added, when 

 a slight effervescence is produced, the liquid taking a yellow- 

 green colour, and the fibres bleaching almost instantaneously. 

 The yarn is then at once washed and wrung, and then put 

 into a clean saucer and moistened with a few drops of 

 ammonia. The colour of the fibres must then be at once 

 examined, for the jute fibres take a blue red colour, whilst the 

 flax or hemp takes a yellow tint streaked with pink. 



Jute may also be distinguished from flax and hemp by 

 testing in an aqueous solution of iodine. Under this test the 

 jute fibre assumes a deep brown colour, while to flax and 

 hemp fibre a blue or violet colour is given. 



Jute also gives the lignin reaction of a yellow colour when 

 treated with iodine and sulphuric acid. 



