Chapter 26 Section 3 Longitude and Latitude Determination and Map Surveying and Mapping in the Qianlong Period

Since the Junggar tribe had not yet been included in the territory of the Qing Dynasty, the survey and mapping during the Kangxi period could only reach the Hami area in the northwest. In the 20th year of Qianlong (AD 1755), the Qing army attacked from Uliasutai (now Zabharante, Mongolia) and Barkol (now Barkol, Xinjiang), and invaded Ili, and the north and south of Tianshan Mountains were initially pacified.In the second year, Qianlong ordered He Guozong, the censor of the capital, to lead Westerners to Xinjiang for surveying and mapping.Since February, it has been divided into two routes, the south and the north, with Nu San in charge of the north and He Guozong and Ha Qing'a in the south.Since the rebellion on Tianshan South Road had not been completely subsided, only the Turpan area and the Kaidu River basin were surveyed, and the surveying and mapping was mainly carried out on Tianshan North Road until October of that year.

In the twenty-fourth year of Qianlong (AD 1759), the Qing army conquered Kashgar (now Kashgar City) and Yarkand, and the north and south roads of Tianshan Mountain were completely pacified.In May of that year, Qianlong sent Ming Antu to lead a team to survey and map various places on Tianshan South Road, as far as Tashkent, Samarkand, and Kashmir. It lasted for nearly a year and ended in March and April of the following year. The scope of these two surveys is west of Hami, east and south of Lake Balkhash, and there are at least 90 locations where latitude and longitude were measured.Although the absolute position of each point is not necessarily correct, its relative position is relatively accurate.The difference from the Kangxi period is that the person in charge of surveying and mapping has been completely held by Chinese officials, and Western missionaries have served as their assistants and specific staff. The missionaries who participated include FLArrocha, Espingha (JE- spinha) and Gopil (Antvine Gaubil) et al.

So far, the latitude and longitude measurement of the whole of China has been completed, but most countries in Europe, the birthplace of this technology, have not yet started or completed their own geodetic survey.This shows that China's map surveying and mapping has once again come to the forefront of the world.