There are a few surviving examples of books printed in the late Song Dynasty using movable type printing. This includes Zhou Bida's "Notes of The Jade Hall" () printed in 1193 using the method of baked-clay movable type characters outlined in the "Dream Pool Essays". Yao Shu (1201–1278), an advisor to Kublai Khan, once persuaded a disciple Yang Gu to print philological primers and Neo-Confucian texts by using what he termed the "movable type of Shen Kuo". Wang Zhen (fl. 1290–1333), who wrote the valuable agricultural, scientific, and technological treatise of the "Nong Shu", mentioned an alternative method of baking earthenware type with earthenware frames in order to make whole blocks. Wang Zhen also improved its use by inventing wooden movable type in the years 1297 or 1298, while he was a magistrate of Jingde, Anhui province. The earlier Bi Sheng had experimented with wooden movable type, but Wang's main contribution was improving the speed of typesetting with simple mechanical devices, along with the complex, systematic arrangement of wooden movable type involving the use of revolving tables. Although later metal movable type would be used in China, Wang Zhen experimented with tin metal movable type, but found its use to be inefficient.