Chapter 61 Section 12 The Scientific Activities of Emperor Kangxi

Aixinjueluo Xuanye [ye page], the holy patriarch of the Qing Dynasty, was commonly known as Emperor Kangxi because his year name was Kangxi.He is the Holy Master of the Qing Dynasty. He reigned for 61 years and established the foundation of the Qing Dynasty.He is both civil and military, erudite and talented, especially in science and technology, and made great contributions to China's science and technology at that time. Therefore, it is not an exaggeration to call him an outstanding scientist in the Qing Dynasty. In 1661, eight-year-old Kangxi became emperor. In 1667, at the age of 14, he came to power.At the beginning of his accession to the throne, he faced a fierce struggle between the Chinese and Western calendars.After the "Shixian Calendar" was promulgated in the second year of Shunzhi (1645 A.D.), some old-fashioned people continued to oppose it, but they failed because Tang Ruowang was deeply favored by Emperor Shunzhi.In the seventeenth year of Shunzhi (1660 A.D.), Yang Guangxian, a health official in Xin'an, made another attack, accusing Tang Ruowang of "stealing Zhengshuo's power to the West" with the words "According to Western New Law" on the cover of "Shi Xian Li". In 1664, three years after Kangxi ascended the throne, Yang Guangxian wrote again, accusing Tang Ruowang of treason, advocating that "it is better to have no good calendar in Zhongxia than to have Westerners in Zhongxia".Obai, who was in charge of the government at that time, imprisoned Tang Ruowang and another Jesuit Nan Huairen (F. Verbiest) who worked in Qintianjian.Coincidentally, in April of that year, the capital suffered an earthquake and the palace suffered another fire. This was regarded as a warning from heaven in ancient times, so the Empress Dowager ordered her to be released.However, the "Shixian Calendar" was also abandoned, and the old calendar "Datong Calendar" and "Hijli Calendar" were restored. Yang Guangxian, who did not understand the calendar at all, was appointed as the supervisor of Qin Tianjian. Tang Ruowang passed away in 1666. In 1669, Nan Huairen wrote a letter criticizing the errors of the old calendar, demanding that Tang Ruowang's case be brought to light, and the dispute between the old and new calendars arose again.

At that time, none of the officials in the court knew the calendar, and Kangxi faced the difficult problem of adjudicating right and wrong.Kangxi, who was only 16 years old, fully demonstrated his ingenuity, and ordered the two parties in dispute to "predict the shadow of the sun at noon, and test whether it agrees or not".He also ordered 20 people, including the University Scholars, to go to the Beijing Observatory to test the accuracy of the beginning of spring, the time of rain, the positions of the moon, Mars, and Jupiter, etc., as proposed by both parties.As a result, Nan Huairen's predictions were in line with each item, but the calculations made by Shang Shu were all wrong.As a result, Kangxi deposed Yang Guangxian, appointed Nan Huairen as the deputy supervisor of Qin Tianjian, and compiled the calendar.Kangxi was greatly shocked by this incident, and he made up his mind to learn scientific knowledge. "Whenever there is spare time, he concentrates on astronomy and calendar for more than 20 years, so he knows the general situation and does not cause confusion." He went south one after another. Missionaries such as Huairen, Zhang Cheng, and Bai Jin learned astronomy, mathematics, physics, medicine, geography, and artillery manufacturing. At the same time, they also learned traditional calendar knowledge from Mei Wending, a famous Chinese mathematician at that time. , Become a monarch who is proficient in Chinese and foreign science and technology.

He used an instrument with a telescope to make topographic surveys in the field, and measured the height of mountains and the distance between any two points; He used a quadrant to measure the height of the sun at noon, and then calculated the altitude of the local North Pole; He used the measurement results of the sundial to calculate the length of the shadow at noon that day; He once predicted the solar eclipse on February 28, 1690, and led his ministers to the observatory to verify the correction on that day; In 1689, when he toured Jiangning Prefecture in the south, he studied the presence of Canopus according to the altitude of the local North Pole, and then corrected the mistakes in the records of the Canopus in Linhuang (in Rehe), the capital of Liao Dynasty, in "History of Liao·Mu Zongji";

... Under the advocacy of Emperor Kangxi, Western modern science and technology spread rapidly in China, and its influence expanded rapidly. China's inherent science and technology also took this opportunity to have a certain degree of revival. Among Kangxi's scientific activities, the most representative ones are the compilation of "The Essence of Mathematics and Physics" and the surveying and mapping of national maps.