Born a peasant in 1400s Korea (during the Joseon dynasty), Jang's great intelligence and skill saw him rise to a position in the royal palace. A scientist, inventor and astronomer, he created advanced celestial globes to measure astronomical movements, researched printing presses and water clocks, worked with a team to invent Korea's first sundial and their first rain gauge, improved metallurgical knowledge that enabled Korean weaponry to develop, and created the world's first water gauge. After a sedan chair he built for the king broke, he was imprisoned and later expelled from the palace, after which records of him cease. TimeWatch prefers it that way.
Jang Yeong-sil on Wikipedia
Joseon Dynasty on Wikipedia