Gezhi jingyuan 格致鏡原

Gezhi jingyuan 格致鏡原 "Mirrored contexts for thorough investigations" is an encyclopaedia compiled during the Qing period 清 (1644-1911) by Chen Yuanlong 陳元龍 (1652-1736), courtesy name Guangling 廣陵, style Qianzhai 乾齋, Gaozhai 高齋 or Guangye Jushi 廣野居士, posthumous title Wenjiangong 文簡公, from Haining 海寧, Zhejiang. Chen's collected writings are called Airitang shi 愛日堂詩 and Airitang ji 愛日堂集. He compiled several collections on rhapsodies, Lidai fuhui 歷代賦彙 (and some supplements), and the "brush-notes-style" collections (biji 筆記) Bizhou ji 敝帚集, Dengying ji 登瀛集, Quesao ji 卻掃集, Huanzhao ji 環召集 and Nangai ji 南陔集.

In 100 juan or fascicles, the Gezhi jingyuan assembles all kinds of literary sources concerning material objects. These are categorized into 30 themes, with 886 sub-chapters. The quotations are mainly taken from the Confucian Classics and writings on history, but also, and to a lesser extent, from miscellaneous writings, novels, "wild histories", or dictionaries. The title is derived from the Neo-Confucian concept of thorough investigation to perceive the Heavenly order, which is inherent in all objects. Most objects are described with a lot of sources, but there are also some, to which not a lot of material is provided, like the armillary sphere (huntianyi 渾天儀), the water clock (kelou 刻漏), or the houqi 候氣 apparatus to determine the onset of spring. The sources are indicated in all cases.

There is a print from 1717 created by Master Chen 陳氏 in Guangzhou, a reprint by the same person from 1735, a print by the Shanghai Tongshu Press 上海大同書局 from 1888, and one by the Jishan Press 積山書局 in Shanghai from 1896. The Gezhi jingyuan is included in the series Siku quanshu 四庫全書.