Sòng Jǐngchāng 宋景昌
Native of Yángzhōu. Active in the late Dàoguāng and early Xiánfēng decades (1830s–1850s). Birth and death years not securely recorded (CBDB id 125613 confirms the name and dynasty but supplies no dates).
A textual-critical scholar associated with the Yíjiātáng 宜稼堂 cóngshū compilation of Yù Sōngnián 郁松年 (Yángzhōu, c. 1842), which recovered and printed several previously-lost SòngYuán mathematical works: 秦九韶 Qín Jiǔsháo’s KR3fc008 Shùshū jiǔzhāng, 楊輝 Yáng Huī’s KR3fc010 Yáng Huī suànfǎ and KR3fc011 Xiángjiě jiǔzhāng suànfǎ, and 朱世傑 Zhū Shìjié’s KR3fc017 Sìyuán yùjiàn. Sòng Jǐngchāng’s principal scholarly contribution was the textual-critical apparatus Xiángjiě jiǔzhāng suànfǎ zhájì 詳解九章算法札記 (KR3fc012), a running notebook of textual emendations and procedural verifications produced as he edited Yáng Huī’s Xiángjiě for the cóngshū. The work systematically collates the recovered Korean Chosŏn recension against the Sòng-fragment survivals in the Yǒnglè dàdiǎn and supplies emendations where the two lines diverge, accompanied by cǎo (procedural-working) verifications of each restored passage.
Sòng Jǐngchāng’s role in the 1842 Yíjiātáng recovery was parallel to 沈欽裴 Shěn Qīnpéi’s and 羅士琳 Luó Shìlín’s roles in the parallel Sìyuán yùjiàn recovery project; the three together constitute the principal scholarly team responsible for the Dào-guāng-era re-introduction of SòngYuán algebra to working Chinese mathematics.