The purpose of the carding operation is to open out the fibres in the wool. Originally, carding was done by hand with two leather surfaces, much like butter pats, the inner faces of which were studded with wire nails. Between these two surfaces the wool was rubbed until all the fibres were opened out. In woolen manufacture carding is more violent and seeks to lay the fibres in all directions. Worsted carding aims to separate the fibres, but also to keep them as closely parallel as possible. [Illustration: _Woolen card. Feed end_] [Illustration: _Woolen card. Condenser end_] [Illustration: _Back Washing_] [Sidenote: _The Card_] The carding machine is somewhat similar to that used for cotton (see page 22). The wool is automatically fed between the feed rollers, which revolve in opposite directions and are armed with heavy teeth. From the feed a roller known as the licker-in starts the wool on its course over a number of cylinders, each of which is surrounded by several toothed rollers known as workers. Each worker has a smaller companion roller, revolving at a higher speed, which derives its name of stripper from the fact that its function is to take the wool off the worker and deliver it to the next worker. The last roller, known as the fancy, raises the wool off the cylinder to be caught by the doffer. The doffing-comb lifts the wool in a filmy sheet of fibres, which is condensed into a thick untwisted rope by passing through a funnel on to the balling-head. This rope, which is about an inch and a half in diameter, is known as a sliver. A certain length of it is automatically rolled into balls and these are taken into the back-wash room. From a loose unrelated mass the wool has now been transformed into a continuous strand of more or less uniform diameter. [Illustration: _Gilling before combing_] 3. BACKWASHING AND GILLING A back-wash machine takes several of the carded slivers and combines them into one. The slivers pass through several baths which rinse them thoroughly and are then slowly drawn through a drier. The process is quite similar to scouring, except that it is very much less violent. [Sidenote: _Combining and Drawing Slivers_]