The Gujin Tushu Jicheng (), also known as the Imperial Encyclopaedia, is a vast encyclopedic work written in China during the reigns of the Qing dynasty emperors Kangxi and Yongzheng. It was begun in 1700 and completed in 1725. The work was headed and compiled mainly by scholar Chen Menglei (). Later on Jiang Tingxi helped work on it as well. It is also sometimes called the Qinding Gujin Tushu Jicheng (). The encyclopaedia contained 10,000 volumes. Sixty-four imprints were made of the first edition, known as the Wu-ying Hall edition. The encyclopaedia consisted of 6 series, 32 divisions, and 6,117 sections. It contained 800,000 pages and over 100 million Chinese characters, making it the largest leishu ever printed. Topics covered included natural phenomena, geography, history, literature and government. The work was printed in 1726 using copper movable type printing. It spanned around 10 thousand rolls (). To illustrate the huge size of the Gujin Tushu Jicheng, it is estimated to have contained 3 to 4 times the amount of material in the Encyclopædia Britannica Eleventh Edition. In 1908, the Guangxu Emperor of China presented a set of the encyclopaedia in 5,000 fascicles to the China Society of London, which has deposited it on loan to Cambridge University Library. Another one of the three extant copies of the encyclopedia outside of China is located at the C.V. Starr East Asian Library at Columbia University. A complete copy in Japan was destroyed in the 1923 Great Kantō earthquake. One of Yongzheng's brothers patronised the project for a while, although Yongzheng contrived to give exclusive credit to his father Kangxi instead. Compilation The Kangxi Emperor hired Chen Menglei of Fujian to compile the encyclopedia. From 1700 to 1705, Chen Menglei worked day and night, writing most of the book, including 10,000 volumes and around 160 million words. It was originally titled the Compendium or Tushu Huibian (图书汇编). By 1706 the book's first draft was completed, and the Kangxi emperor changed the title to Gujin Tushu Jicheng. When the Yongzheng emperor ascended the throne, he ordered Jiang Tingxi to help Chen Menglei finish the encyclopedia for publication by around 1725. Outline The 6 series are as follows. Heavens/Time/Calendrics (历象): Celestial objects, the seasons, calendar mathematics and astronomy, heavenly portents Earth/Geography (方舆): Mineralogy, political geography, list of rivers and mountains, other nations (Korea, Japan, India, Kingdom of Khotan, Ryukyu Kingdom) Man/Society (明论): Imperial attributes