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ferent flavor. By degrees a more scientific method is being 

 adopted. It is gradually becoming the custom to heat the alcohol 

 and then add the desired bacteria in pure culture. 



Maceration Industries. The separation of linen from the flax 

 stem is a process usually brought about by bacterial activity. 

 The valuable linen fibers and the coarser wood are so bound to- 

 gether by a cementing substance that it is seldom possible to 

 separate them by mechanical means. In order to decompose 

 this binding material several methods may be employed, the prin- 

 ciple of each being to subject the stems to suitable heat and mois- 

 ture to encourage bacterial growth. A fermentation is thus started 

 which softens the gummy substance holding the fibers together 

 and permits their separation. This " water-retting " process is 

 supposedly brought about by anaerobic bacteria. 



The same principle is applied in the manufacture of jute and 

 hemp and in the preparation of cocoanut fiber. In the tanning 

 of leather, the preparation of sponges, and the curing of tobacco 

 bacteria also play a large part. 



