Paper manufacture began in Britain in the late C15. It was made by hand at first, from torn-up linen or cotton rags beaten up in water to a pulp. The pulp was sometimes boiled in caustic soda to remove impurities, and sometimes bleached to make fine quality white paper. The pulp was made into paper, a sheet at a time, in a mould made of fine copper wires. The wet paper sheets were then squeezed under a screw press to remove excess water, then hung on ropes in a drying loft. If intended for printing, the sheets were dipped in a gelatine size then dried again. In around 1650 the Hollander roller beater was invented. In the 1820s resin and alum were added at beating stage instead of the separate gelatine size and second drying stage. In the early C19 wood fibres began to replace old rags. Wood pulp and waste paper became the raw materials. Esparto grass from Spain and North Africa was introduced c.1860. Making paper in a continuous length began with the fourbrinier machine in 1807. This was imrpoved in 1820 by a steam drying section patented by Thomas Bonsor Crompton. By about 1830 half the paper made in Britain was made by machine. By 1860 95% was machine made. A typical 1860s paper mill would comprise reservoirs and filter beds for controlling the quality of the water, a rag store, sorting room, rope chopper, dusting house, Hollander beating house, boiling kiers, bleach house, paper making machines, paper cutting machines, glazing house, warehouse, boiler house and a copious water supply usually from a river (William Jones, 1996, Dictionary of Industrial Archaeology).