Note:  Do not rely on this information. It is very old.

Felt

Felt, a fabric produced by the adhesion of the fibres of hair and wool, without any process of weaving. Hair has a serrated surface, the barbs pointing towards the upper extremity, so that when a mass of hair is subjected to pressure the barbs of one hair become firmly fixed in the indentations of another lying in the opposite direction. Wool felts more easily than ordinary hair owing to its tendency to curl, but the natural grease must be previously abstracted. Felting is probably an older invention than weaving; it was used at a very early date by the Armenians and Tartars in the manufacture of clothing and tent-covers, and is mentioned by Xenophon, Pliny, and Marco Polo. Moisture, as well as pressure, is necessary in felting, and heat is also serviceable. Thus in the manufacture of carpets, articles of clothing, and similar commodities, the process is as follows: - The wool is first of all carded out into a number of fine laps of the required length and breadth; these are then placed one upon the other until the desired thickness is obtained. The mass of wool is then moistened and passed between rollers, some of which are heated internally with steam. This is the final stage in the production of the felt.