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Rh being put aside as useless, and the seams cut open or thrown out. Standing at a bench, the top of which is wire netting, the sorter takes rags from a pile, and cuts them on a scythe-like knife which stands out obliquely from the bench. A large amount of dust escapes through the netting, and the rags are sorted into bins as more suitable for one class of paper than another. The rags are next taken to the willow or dusting machine, where they are subjected to violent treatment, the teeth of the machine carrying the rags against other teeth, giving them a thorough shaking and loosening the dust, which falls away. As they are cleaned, the rags are taken to the top of the building by a travelling band and dropped into the mouth of a boiler prepared to receive them. For rags a special spherical rotary boiler is employed, and when a charge has been filled in, a definite quantity of a solution of caustic soda in water is added. The lid is securely fastened, steam is passed in, and the boiler is kept rotating slowly for about eight hours. When the dirt in the rags has been thoroughly loosened the rotation is stopped, steam is shut off, the dirty water is run off, clean water is run in. The boiler is again revolved, the rags rinsed, and then the lid is removed and the boiler emptied by continuing the revolution.

Next comes the washing and breaking, both of which may be carried out in the beating engine. The beating engine, of the Hollander type, consists of a large vessel with rounded ends, with a central division running down the length of the engine. Two cylinders revolve: one, a very heavy cylinder known as the beating roll, reaches to the bottom of the engine and bears a number of knives on its surface, which knives, in conjunction with a bedplate also bearing knives, break the rags into smaller fragments and open the threads,