In the 1930s, wallpaper designs changed dramatically. Before machines were introduced, wallpaper was block-printed by hand. The process was slow and expensive, so manufacturers sought new methods to increase production. In Darwen, Lancashire, Potters & Ross, a cotton printing company, devised a machine that made it possible to produce a large volume of intricately detailed wallpaper. The machine featured rollers inked with ink from troughs underneath.