1441 (Sejong 23) August Hojo (户曹) to suggest that you install cheukwoogi, cheukwooe In five of the following year the newly established system, and Seoul, and each also made cheukwoogi (道) of gunhyeon (郡县) was installed. Prior to the cheukwoogi originally engineered for each province to determine the distribution of the rainfall was very uncomfortable. In other words, non-flat a few inches deep through the dirt by the rain would have bled to tell me why should investigate to 112, where the soil is dry I do not think jeoteumyi could not figure out exactly what is rainfall. But over a period of cheukwoogi really in them by measuring the depth of pools of rainwater where it is supposed to rain.

The inner diameter cheukwoogi this jucheok (周尺) a 7-inch (14.7cm), height is about 1.5, which ships with the cylinder, the cylinder when it rains the rain water can not get this house is built on leave. The depth of water in the pools cheukwoogi Now [尺] is measured. In other words, major (台) to create a gwansanggam cheukwoogi put on the cars to receive the rain, gwansanggam the ruler to measure the depth of water jucheokeuro direct reports. Central to the gwansanggam local gamyeong each degree (监营) were installed. Initially created by rail, but even after the writing was made of copper, the magnetic region (瓷器) · wagi (瓦器) and was not writing. Made of wood or bamboo, were used jucheokeun.

Sejong the history of science cheukwoogi when the world's most significant thing is the fact that first were used. In Europe, in Rome, Italy, in 1639 the first cheukwoogi Telly B. gas observe the rainfall is hayeotdago. In Paris since 1658, was observed in the UK since 1677. In South Korea, already in May 1442 cheukwoogi rainfall was measured, which for about 200 years, faster than Italy. kumyoung the cheukwoogi 1837 (Paper 3) was created to be designated as Treasure No. 561 houses on the Meteorological Agency said.