FELT, from Dutch vitt, a fabric made from wool, or wool and hair, or fur, without weaving, by rolling, beating and pressure, generally with the use of lees or size. The process of felting is similar to that of fulling. The fibres of fur, hair or wool are rough in one direction only, and thus they can glide among each other in such a way that when the mass is agitated the anterior extremities slide forward in advance of the body or posterior half of the hair and serve to entangle and contract the whole mass to gether. Articles of felt, such as rugs, carpets, clothing and hats, have been made from remote antiquity, and are still made and widely used among various Asiatic peoples. Modern uses of felt include also carriage linings, piano forte hammers, surgical dressings, etc. Legend ascribes the invention of felt to Saint Clement, who found that carded wool placed in his shoes to protect his feet while on a pilgrimage worked into a felt by the pressure and moisture; but it has a much earlier origin, being apparently known in Homer's time. The Saracens used it for tents, and it was probably introduced into Europe at the time of the Crusades. In Europe and America felt cloths are also made for sev eral purposes, the finer kinds especially for carpets and tablecovers, which may be dyed or printed and finished in various ways. The first mechanical process for the making of felt was invented about 1820 by the American J. R. Williams. Various details have since been added, but the main principle remains the same. The wool is carded into laps of the length and breadth of the web to be made. Layers of
these are placed one above another until the desired thickness is secured, the outer layers being generally of finer texture than the inte rior. The whole is now passed between rollers partly immersed in water. In the machinery by which felt fabrics are produced, rollers with a rubbing and oscillating movement have gen erally an important action. The materials com monly used for felt hats are the furs of the rabbit and other animals and the wool of sheep. The latter material is employed for common and medium hats, only the finer felt hats being made from fur. The hats after being stiffened are dyed. They now undergo the operation of blocking, in order to give them their proper shape. Coarse varieties of felt are used for covering steam boilers and cylinders, steam-pipes, and otherwise as non-conductors. Asphalted felt is a coarse felt saturated with pitch, asphalt or coal-tar and used for covering sheds and other buildings, and a superior kind called inodorous felt is used for lining damp walls. Another kind is asbestos felt. For some of these the process of manufacture is similar to that employed in making paper. In the United States the felt industry has about 45 establishments, producing goods valued at approximately $12,000,000 yearly. The principal products are felt cloths, boot and shoe linings, upholstery felts, trimmings and lining felt, felt shirts and belts for paper manufacture. Con sult "Felt and in Murphy's 'The Tex tile Industries' (Vol. II, London 1912). See HAT.