The whole process is a typical fermentation. A disagreeable odour arises from the fermenting flax, and the liquid after the fermentation is filled with products which make valuable manure. The process has not been scientifically studied until very recently. The bacillus which produces the "retting" is known now, however, and it has been shown that the "retting" is a process of decomposition of the pectin cement. No method of separating the linen fibres in the flax from the wood fibres has yet been devised which dispenses with the aid of bacteria. Jute and Hemp.--Almost exactly the same use is made of bacterial action in the manufacture of jute und hemp. The commercial aspect of the jute industry has grown to be a large one, involving many millions of dollars. Like linen, jute is a fibre of the inner bark of a plant, and is mixed in the bark with a mass of other useless fibrous material. As in the case of linen, a fermentation by bacteria is depended upon as a means of softening the material so that the fibres can be disassociated. The process is called "retting," as in the linen manufacture. The details of the process are somewhat different. The jute is commonly fermented in tanks of stagnant water, although sometimes it is allowed to soak in river water for a sufficient length of time to produce the softening. After the fermentation is thus started the jute fibre is separated from the wood, and is of a sufficient flexibility and toughness to be woven into sacking, carpets, curtains, table covers, and other coarse cloth. Practically the same method is used in separating the tough fibres of the hemp. The hemp plant contains some long flexible fibres with others of no value, and bacterial fermentation is relied upon to soften the tissues so that they may be separated. Cocoanut fibre, a somewhat similar material is obtained from the husk of the cocoanut by the same means. The unripened husk is allowed to steep and ferment in water for a long time, six months or a year being required. By this time the husk has become so softened that it can be beaten until the fibres separate and can be removed. They are subsequently made into a number of coarse articles, especially valuable for their toughness. Door mats, brushes, ships' fenders, etc., are illustrations of the sort of articles made from them.