<Tr> <Td> </Td> <Td> This section does not cite any sources . Please help improve this section by adding citations to reliable sources . Unsourced material may be challenged and removed . (April 2015) (Learn how and when to remove this template message) </Td> </Tr> <P> A printing press, in its classical form, is a standing mechanism, ranging from 5 to 7 feet (1.5 to 2.1 m) long, 3 feet (0.91 m) wide, and 7 feet (2.1 m) tall . The small individual metal letters known as type would be set up by a compositor into the desired lines of text . Several lines of text would be arranged at once and were placed in a wooden frame known as a galley . Once the correct number of pages were composed, the galleys would be laid face up in a frame, also known as a forme., which itself is placed onto a flat stone,' bed,' or' coffin .' The text is inked using two balls, pads mounted on handles . The balls were made of dog skin leather, because it has no pores, and stuffed with sheep's wool and were inked . This ink was then applied to the text evenly . One damp piece of paper was then taken from a heap of paper and placed on the tympan . The paper was damp as this lets the type' bite' into the paper better . Small pins hold the paper in place . The paper is now held between a frisket and tympan (two frames covered with paper or parchment). </P> <P> These are folded down, so that the paper lies on the surface of the inked type . The bed is rolled under the platen, using a windlass mechanism . A small rotating handle is used called the' rounce' to do this, and the impression is made with a screw that transmits pressure through the platen . To turn the screw the long handle attached to it is turned . This is known as the bar or' Devil's Tail .' In a well - set - up press, the springiness of the paper, frisket, and tympan caused the bar to spring back and raise the platen, the windlass turned again to move the bed back to its original position, the tympan and frisket raised and opened, and the printed sheet removed . Such presses were always worked by hand . After around 1800, iron presses were developed, some of which could be operated by steam power . </P> <P> The function of the press in the image on the left was described by William Skeen in 1872, </P>

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