Joseon - Science and Technology

Science and Technology

The Joseon Dynasty under the reign of Sejong the Great was Korea's greatest period of scientific advancement. Under Sejong's new policy Cheonmin (low-status) people such as Jang Yeong-sil were allowed to work for the government. When Jang was very young he built machines to help make work easier, and supervised the building of aqueducts and canals. Jang eventually was allowed to live at the royal palace, where he led a group of scientists to work on advancing Korea's science.

Some of his inventions were an automated (self-striking) water clock (the Jagyeokru) which worked by activating motions of wooden figures to indicate time visually (invented in 1434 by Jang), a subsequent more complicated water-clock with additional astronomical devices, and an improved model of the previous metal movable printing type created in the Goryeo Dynasty. The new model was of even higher quality and was twice as fast. Other inventions were the sight glass, and the udometer.

Also during the Joseon Dynasty Heo Jun, a court physician, wrote a number of medical texts, his most significant achievement being Dongeui Bogam, which is often noted as the defining text of Traditional Korean medicine. The work spread to China and Japan, where it is still regarded as one of the classics of Oriental medicine today.

The highpoint of Korean astronomy was during the Joseon period, where men such as Jang created devices such as celestial globes which indicated the positions of the sun, moon, and the stars. Later celestial globes (Gyupyo, 규표) were attuned to the seasonal variations.

The apex of astronomical and calendarial advances under King Sejong was the Chiljeongsan, which compiled computations of the courses of the seven heavenly objects (five visible planets, the sun, and moon), developed in 1442. This work made it possible for scientists to calculate and accurately predict all the major heavenly phenomena, such as solar eclipses and other stellar movements. Honcheonsigye is an astronomical clock created by Song I-yeong in 1669. The clock has an armillary sphere with a diameter of 40 cm. The sphere is activated by a working clock mechanism, showing the position of celestial objects at any given time.

Kangnido, a Korean-made map of the world was created in 1402 by Kim Sa-hyeong (김사형, 金士衡), Yi Mu (이무, 李茂) and Yi Hoe (이회, 李撓). The map was created in the second year of the reign of Taejong of Joseon. The map was made by combining Chinese, Korean and Japanese maps.

The first soft ballistic vest, Myunjebaegab, was invented in Joseon Korea in the 1860s shortly after the French campaign against Korea. Heungseon Daewongun ordered development of bullet-proof armor because of increasing threats from Western armies. Kim Gi-du and Gang Yun found that cotton could protect against bullets if thick enough, and devised bullet-proof vests made of 30 layers of cotton. The vests were used in battle during the United States expedition to Korea, when the US Navy attacked Ganghwa Island in 1871. The US Army captured one of the vests and took it to the US, where it was stored at the Smithsonian Museum until 2007. The vest has since been sent back to Korea and is currently on display to the public.