'''' () was a type of Korean fire arrow rocket, used during the era of the Joseon Dynasty (1392–1897). Multiple sin'gijŏn could be launched by (multiple rocket launcher).
==History== During the late 14th century, in order to gain ascendancy at sea against Japanese pirates ( or ), fire arrows called () were used, which would become the predecessor of the sin'gijŏn''. The Koreans had tried to acquire rockets and gunpowder and their production methods from China. The Chinese, however, regarded the technology of gunpowder as a state secret and restricted access to it and trade in its nitrous raw materials (which could only be found in China). The Koreans therefore sought to acquire the manufacturing secrets of gunpowder for themselves and, in 1374 (–1376), Ch'oe Musŏn was able to bribe a Chinese merchant to obtain the secret formula for manufacturing gunpowder, as well as limited technical knowledge about Chinese firearm and cannon technology. He also successfully extracted potassium nitrate from the soil and rocks from Japanese trade routes, and developed Korea's first gunpowder.
Discovered by embedding cosine similarity (sentence-transformers MiniLM, 384-dim).