Mechanisation of this finishing process in the 11th century made life much easier for the fuller. Water power was used to work fulling stocks, a machine with two large wooden hammers raised on tappets. The cloth was contained in a trough – the stock – and was repeatedly beaten by the rising and falling hammers. Such hammers did generate heat and heavily felted
cloth was produced. It took several hours to get the right degree of felting. The piece shrank by about one third of its length and one quarter of its width.
By the 13th century, fulling stocks were in use in this area wherever a river provided sufficient water power. Fullers earth continued to be used for coarser cloths but during the18th century, oil soap was used for finer ones. Some clothiers ran their own fulling mills which was often the base of their operations. Ladydown fulling mill was built in 1726 and water power was still used until well into the 19th century.
The patent for a rotary fulling machine was obtained by John Dyer, a Trowbridge engineer in 1833. The two ends of a piece of cloth were lightly tacked together so that the cloth could pass continually around rollers which generated friction and thus heat. Later a synthetic detergent was used instead of soap or fullers earth.
The wet cloth was stretched and dried on a tenter rack. Wooden frames were built outside the mill but near to it, to prevent valuable cloths being stolen.
Blunt headed nails were driven at intervals into the frames and the selvedges of the cloth were pulled evenly and hooked onto the nails. Hence the expression being on tenter hooks!
From 1727 until 1770, all cloths were measured by inspectors and ‘sealed’.
After mechanisation, a tenter machine was used to dry the cloth. It also removed creases and straightened the fabric. The cloth was still stretched to the correct width on tenter hooks.