Before wool can be spun into yarn for knitting or weaving into cloth, it first must be brushed, or carded. This tedious task was successfully mechanized in the second half of the 18th century by several British inventors, principally Richard Arkwright and James Hargreaves. By the late 1780s carding machines began to be built in the United States, carding as much wool in minutes as a hand-carder could do in as many hours. By 1811 the federal government estimated that on average every town had at least one carding mill where farm families could bring their wool and pay to have it carded. This made the domestic production of cloth much easier by removing this time-consuming step. As textile factories multiplied in the 19th century, however, people stopped making their own cloth at home, and custom carding mills declined. Today, of course, there are no longer thousands of neighborhood carding mills in America catering to people who make their own cloth at home by hand. The same technology, however, is still used in modern cotton and woolen factories.

Since 1773, carding machines have had the same basic design as they do today. They consist of a series of round brushes that align wool fibers as the wool passes from one end of the machine to the other. Each cylinder is covered with bent iron wires, which grab wool in one direction and release it in another.

Clean but tangled wool is fed into the machine from a conveyor belt, called a feed apron. Two small cylinders--called licker-ins—transfer the wool from the apron to the tumbler, which deposits it on the large main cylinder. This cylinder carries the wool through the machine. Along the way, it is removed by workers. Strippers then take it from the workers and deposit it back on the main cylinder. Near the end of the machine, a fancy with long bristles fluffs the wool up on the main cylinder so that a doffer can remove it. The wool is rolled up into rolls or silvers for spinning as it passes between a fluted cylinder and a concave shell.