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.
Further information: List of Chinese inventions. The Four Great Inventions (simplified Chinese: åå¤§åæ; traditional Chinese: åå¤§ç¼æ) are inventions from ancient China that are celebrated in Chinese culture for their historical significance and as symbols of ancient China's advanced science and technology.