Paper had been invented in China in the 8th century, but it was kept secret for a long time. In Europe hand-made paper was available from about 1450. It was cheaper than parchment but still expensive, and the early printing was a slow process. Therefore, books remained rare. In 1800 the first machines for making paper from wood pulp were invented. New kinds of inks were also invented for various purposes, and machines were driven by steam engines and later by electricity.