Xǔ Guìlín 許桂林 (zì Tóngshū 同叔, hào Yuènán 月南; 1779–1821; native of Hǎizhōu 海州, Jiāngsū) was a mid-Qīng Confucian scholar, mathematician and astronomer of the Yángzhōu / Hǎizhōu kǎozhèng circle. He is best known for the Xuānxī tōng 宣西通 (KR3fa034 and KR3fa035) — a four-juǎn treatise (with companion single-juǎn digest) which uses the Hóngfàn 洪範 “xuán” 璿 and Yáo diǎn “qīzhèng” canonical passages as the framework for an integrated presentation of the Jesuit-Tychonic-Keplerian astronomy. The work is one of the most influential late-Jiā-qìng / early-Dào-guāng synthesist texts: Xǔ argues, with great philological care, that the Hóngfàn’s “xuánjī yùhéng” 璿璣玉衡 contains in nuce the celestial-and-equatorial coordinate system, the precession-of-the-equinoxes phenomenon, and the qīzhèng planetary apparatus. CBDB id 75781, 1779–1821.