Earthenware, originally a rice steamer, equivalent to the modern steamer. Each piece of earthenware by the upper and lower parts of the composition, the upper part is called "cauldron, holding food to be steamed; its bottom is" grate, there are a number of ventilation holes; the lower part of the "鬲,used to boil water. Most of the bronze earthenware vessels of the Shang dynasty is a cauldron, the earthenware vessel, a cast, and are single, that is, a cauldron and an earthenware vessel.