Chashu 茶疏

Chashu 茶疏 "Comments on tea" is a book on tea compiled during the Ming period 明 (1368-1644) by Xu Cishu 許次紓 (1549–1604), courtesy name Ranming 然明, style Nanhua 南華. He hailed from Qiantang 錢塘 (modern Hangzhou 杭州, Zhejiang), but not much is known about his life. His collected writings, named after his studios Xiaopinshi 小品室 and Danglangzhai 蕩榔齋, are lost.

His short book Chashu is divided into 39 chapters that explain regions of origin, quality grades, methods of harvesting tea leaves, their storage and preparation methods. Although the Chashu focuses on these few points, the descriptions are very detailed. There is one crucial mistake in the text concerning the well on Mt. Jinshan 金山.

The book was first printed in 1607 with the first preface being written by Xu Shiqi 許世奇, and the second one by Yao Shaoxian 姚紹憲. One copy was owned by the library of the Imperial Household Department (neiwufu 内務府), but it was not included in the imperial series Siku quanshu 四庫全書. It is found in the Guang baichuan xuehai 廣百川學海, Chongding Xinshangbian 重訂欣賞編, Jujia bibei 居家必備, Guang baichuan xuehai 廣百川學海本, Baoyantang miji 寶顏堂秘笈 (with the title Xu Ranming Xiansheng chashu 許然明先生茶疏), Xu Shuofu 續說郛, Congshu jicheng chubian 叢書集成初編 and Gujin shuobu congshu 古今說部叢書. It is quoted in the series Chashu quanji 茶書全集 and (in excerpts) in the encyclopaedia Gujin tushu jicheng 古今圖書集成.