When the five-day holiday arrived, Yang Chong reported to the military department; Since Yang Chong knew his usefulness, he originally thought that in the future, he would go to the military department every day to order something, so he would find a reason to slip away. Unexpectedly, Shangshutai had a new arrangement, and Yang Chong, as the head of the Ministry of War, was in charge of the Chang'an Division. The staff department is in charge of the maps handed in by the states of the world, as well as the layout of the city gods, towns, fortresses, and beacons, as well as the internal attachment of ethnic minorities along the border, and the staff department of Chang'an is in charge of Guanzhong, Longyou, the Western Regions, and the southwest.

This is the idea of Yuan Wuji, the head of the Ministry of War, Yuan Wuji is the son of Yuan Xiaoju, the prince of Xunyang County, who knew Duan Wenzhen's arrangement from other channels, and deliberately made some modifications, proposing to hand over the work of the Ministry of Duties to Yang Chong. The problem is that the left-behind bigwigs in Chang'an actually agreed to Yuan Wuji's suggestion, and Yao Wei, the general of Zuotunwei, Dong Chun, the general of Zuo Beishen, and Yang Wensi, Nayan, jointly signed and sent the chapter to Luoyang.

Clear-eyed people immediately saw that they gave Yang Chong a chance to do business, that is, they wanted to use Yang Chong to carry out trade with the Western Regions, and by the way, give Yang Chong a stage to confront Pei Ju. However, for their different purposes, the center, under the impetus of Su Wei, Yuan Shou, and Yang Da, approved this piece of music almost in one day, and after reporting to Emperor Yang Guang of the Sui Dynasty for approval, Su Wei was the right servant of the Shangshu and Duan Wenzhen of the military department issued notices respectively; Duan Wenzhen also sent a private letter to Yang Chong, suggesting that Yang Chong should not start a war and direct trade, or focus on spying on intelligence and investigating suspicious people with Duhu and others.

Yang Chong was actually a little tired of the officialdom, and discussed with Yu Wenkai in Luoyang, and learned that he could not resign, so Yang Chong began to want to delve into something academic. After reading Duan Wenzhen's letter, Yang Chong replied with a letter of his own, saying that he had a new idea, redrawing the map of Guanzhong and Longyou; As for spying on intelligence and checking suspicious persons, he can assist Duhu usurpation, but it can't be his main job, and the Western Regions trade will not interfere, his own job is still in the department, Yang Chong made a report on his work plan and brought it to Duan Wenzhen.

The Chang'an Staff Division was originally the location of the entire Ministry of War, and it was heavily guarded on the side of the Military Department close to the palace; The drawings collected in the staff department are all state secrets, so the guards of the staff department are completely under the responsibility of the palace guards, and almost all the craftsmen and officials in the staff department are employees. Before Yang Chong came, the person temporarily in charge was the junior official Yang Qu.

Yang Qu was born in the Hongnong Yang family, and was Yang Su's concubine, because of the recommendation of Yang Su's uncle Yang Wensi, he got this errand, and is now in his thirties; Seeing Yang Chong in the office room, Yang Qu could only sigh that his life was not good, Yang Chong was born in a poor family, and he sat in the position of the head of the military department in a year, from the official of the seventh grade. Yang Chong had read Yang Qu's information in advance, and said with a smile: "Brother Yang has worked hard these days, and I hope to help you a lot in the future." ”

Yang Qu immediately straightened his position, and Shi Li said: "Director Yang, you are here, and the Chang'an Staff Division will definitely be able to shine." ”

Yang Qu is a concubine and a child of the scholar clan, Yang Chong stopped and said, "Brother Yang, this is going to kill me." But I do have something to discuss with you, I wonder if you are free with Pei Lao and Xu Lao? ”

Yang Chong's Pei Lao is called Pei Bang, who is the pillar of the staff department, from the Pei family in Hedong, and his ability to draw with one hand is unmatched; Xu Lao's name is Xu Sanchuan, born in the army, when he was young, he fought with Gao Gong in all directions, and he had a false position of Zhengbapin, and was responsible for reviewing the drawings sent from all over the country. Yang Chong asked, there must be something to do, Yang Qu smiled: "Now the Chang'an staff department is like a fictitious, new drawings from all over the country are sent to Luoyang, everyone has time, I will go to inform." ”

There were six people in total. Pei Bang is in his sixties, a little hunchbacked, with a good complexion and a smiling look; Xu Sanchuan stood straight, retaining the bearing of a soldier; In addition to Yang Qu, the other three were Cao Tong, Ma Ji, and Wu Zhuo, who were responsible for verifying the drawings in other places. Yang Chong first announced that everything would remain unchanged, and then asked a question: "During the Three Kingdoms, there was a six-body map, do you know?" ”

Pei Bang nodded and replied: "The six bodies of cartography were created by Pei Xiu, the ancestor of our Pei family, but unfortunately they were lost, even in the library buildings of the Pei family, there are only a few fragments of pages. It was only after reading the fragments and the preface of the eighteen articles of the "Yugong Geographical Map" that he became interested in the drawing, but unfortunately he was stupid and dull, and he studied all his life and failed to master this method. Director Yang is rumored to be proficient in Gewu, could it be that he knows this way? ”

Although Yang Chong did not know the details, he knew that Pei Xiu's cartographic six bodies were actually the scale, direction, distance, topography, inclination angle, river, etc., which were commonly used in later legislative maps, but Yang Chong had already made up his mind to follow the methods of later maps, and would not let the Pei family get this reputation. Yang Chong smiled: "This official only understands a little bit, why don't we discuss it together?" ”

Yang Chongge's reputation is outside, and his official position is high, so Yang Qu and others naturally have no objections. Yang Chong first talked about the scale, direction and distance, that is, to make the three unified, unified directions, according to the later generations "up the north, down the south, left west, right east"; The unified scale adopts the scale left by Pei Xiu "to divide one into ten miles, and one inch is a hundred miles"; The distance between the two places should be unified in different drawings of the department, and it is not possible to say 200 miles on one drawing and 180 miles on the other.

Regarding Pei Bang's proposal of height, squareness, and straightness, Yang Chong decided that the topography should be distinguished by the thickness of the color and line, and proposed the concept of dividing the circle with 360 degrees to represent the angle. Yang Qu and the others were stunned all of a sudden, and even after Pei Bang pondered it, his beard trembled, and he sighed: "Lord Yang is really a genius, this method is simple and practical, and almost all the mountains and rivers can be displayed on the drawings." ”

Yang Chongqian said: "This official is also an idea, you will first help me to staff whether it can be practical, if it can be used, we will report to the Ministry of War, and the training of all the officials of the staff department will be promoted to the whole country." Pei Lao, Xu Lao, why don't we make a map of Chang'an within a radius of 500 miles and see how it works? ”

Pei Bang and Xu Sanchuan are naturally willing, if this map can be formed, they will be able to leave a name in history like Yang Chong in the future, and Cao Tong, Ma Ji, and Wu Zhuo will even fight for who to investigate now. The three of them are all experts, and they know that as long as the map is handed in, the Ministry of War will definitely approve it, and now who will investigate, in addition to being able to master the first-hand experience, it is indispensable to get a reward from the imperial court, and in the end, Yang Chong will make a decision, Chang'an City will be returned to Cao Tong, the north and west of the city will be returned to Ma Ji, and the east and south of the city will be Wu Zhuo.

Yang Qu was very surprised when he heard this, this Yang Chong is different from the legend, looking at his speech arrangement, he is completely a qualified official, how can he be unruly in the legend. But when he heard Yang Chong's next sentence, Yang Qu knew that he was wrong, because Yang Chong said: "I gave Duan Shangshu a chapter and attached a copy of this drawing, and named this drawing method the Daye Cartography Method." Everyone work hard, and the court will definitely have a reward. ”