Mao Gong Ding, the bronze tripod cauldron, was excavated at the end of the Daoguang period (1821−50) in Qishan County, Shaanxi. Dings were used widely as ritual vessels and became hierarchical symbols during the Zhou dynasty (circa 1046−256 BC). This is the most famous ding, originally belonging to Mao Gong. There are 497 characters on the inside of the vessel, the longest bronze inscription known to this day. The inscription records the history of the late Western Zhou (circa 1046−771 BC), specifically the reign of Emperor Xuan in the ninth century BC, the service of his uncle the duke of Mao as head of government, and a list of the duke’s honors and rewards. It was a national treasure. The rubbings from the ding in the National Library of China date back to the Xianfeng and Tongzhi periods of the Qing dynasty (1851−74), when they originally were made by Chen Jieqi (1813−84) or his pupil. The images are natural and lifelike, giving a three-dimensional impression. This is a set of full-framed rubbings and is very valuable. Before the work came to the library, it was in the collection of Chen Huaisheng (1928−62). It includes a handwritten inscription by Luo Zhenyu (1866−1940) in large seal style. Chen Jieqi was the first professional collector of full-framed Mao Gong Ding inscriptions, and his rubbings can be considered comparable to the first edition of a rare book.