Gout causes a painful, swollen joint that's so severe that the weight of bed sheets can cause distress. There may also be more than one joint affected with gout. With gout, uric acid -- a normal chemical in the body -- forms crystals that deposit in the joints, causing inflammation and pain.
China has been the source of many innovations, scientific discoveries and inventions. This includes the Four Great Inventions: papermaking, the compass, gunpowder, and printing (both woodblock and movable type). The list below contains these and other inventions in China attested by archaeology or history.
China underwent an industrial revolutionâmass-producing quantities of raw materials like salt and iron on a scale that wouldnât be seen in Europe until the 18th century. During the Song, Chinaâs âfour great inventionsâ were widely used: The compass, gunpowder, paper-making, and printing. Science, technology and engineering reached new heights (such as ship and bridge building, hydraulic engineering, and architecture).