After Liu Tan finished writing these twelve characters, he drew a summary symbol and wrote the six characters of the drawing. Then, seeing Wei Guan also stood up, he pressed his hands repeatedly and said, "You sit down first. Don't worry, I won't hold you accountable."
Wei Guan looked at Liu Tan's expression carefully and sat down cautiously.
After he sat down, Liu Tan asked, "Do you understand?"
Wei Guan was a little hesitant, a little afraid that if he said he didn't understand, it would make Liu Tan unhappy.
Liu Tan seemed to see his hesitation and pointed at the blackboard and said, "Tell the truth."
Wei Guan said honestly: "I don't understand."
Liu Tan circled the word "cartography" and asked, "Do you understand this?"
Wei Guan took a look and didn't quite understand at first, but suddenly he remembered that Liu Tan had told him before that he wanted him to draw maps and make cartography... Isn't that what he meant?
He quickly replied, "I understand. This is the method used to draw maps."
Liu Tan nodded with satisfaction. Talking to smart people is less stressful.
He said, "You haven't come across these concepts before. No, or rather, no one in the entire Han Dynasty knows them except me, so it's normal that you don't understand. Now I will explain the meaning of these words to you."
He drew a circle on the scale factor and said, "This represents the ratio of length to size. From reality to drawings, it must be reduced to a certain extent. However, before that, there are no regulations on how much reduction or the difference from reality. Therefore, when drawing maps, the length and area of real objects are ten times that of the ones on the map."
After hearing this, Wei Guan was still a little confused. He had little contact with maps, so naturally he didn't know how to draw this.
Liu Tan seemed to see through his confusion and quickly said, "Write down these definitions first. I'll explain them systematically to you first, and then we'll go through them in detail later."
Wei Guan could only suppress the doubts in his mind and honestly picked up the pen to write down these definitions on paper - at this time, the paper he used was still unimproved paper.
After Liu Tan finished explaining the ratio, he continued, "The so-called accurate observation is to determine the relative position of landforms and land features. Daoli is the distance between two places by road. Gaoxia is the relative height. Fangxie is the slope of the ground. Yuzhi is the conversion between the actual height and the height on the map. Have you written down all of this?"
Wei Guan said seriously, "I've written it down."
These things are relatively simple, or in other words, they have few words, and since he memorizes them while writing, it is not difficult to remember them.
Liu Tan put his pen down and asked, "Is there anyone who can understand?"
After carefully examining it, Wei Guan said, "I can all see some of the meaning, but I can't put it into words. However, I can see that after Your Highness establishes this set of rules, the relationship between maps and reality will become more accurate and easier to understand. Your Highness is truly talented!"
Liu Tan felt relieved. Fortunately, he didn't meet a stupid student. Fortunately, he had taught classes in place of teachers when he was studying for his master's degree. Otherwise, he really didn't know how to teach.
Wei Guan was extremely excited. He had already realized that this set of map-making rules was very simple and clear, and the maps drawn would be clearer. If there was no war, it would be fine. But once the war broke out, such maps would surely shine.
Although a cartographer may not become famous, he will definitely be reused.
And because Liu Tan had been so cautious in asking him to sign the documents and even restricted his personal freedom, he suddenly realized what was going on.
If it were him, he would do the same.
Wei Guan studied very hard. He knew very well that Liu Tan, who developed this system, would not be able to draw the map himself. So at that time, only he, who had learned this system, would be the most suitable person and might even be recruited by the court.
So even though Wei Guan was a little cautious at the beginning, fearing that asking too many questions would annoy Liu Tan, after he discovered that Liu Tan actually had a good temper and plenty of patience, he began to pay attention to every detail.
Liu Tan was actually pleased to see him like this. Cartography is a meticulous job that requires attention to detail. Otherwise, if there is a problem with one detail, it may cause problems with all the coordinate positioning.
After thoroughly understanding the six principles of cartography, Liu Tan taught him the method of drawing in a plan.
In fact, Ji Li Hua Fang is more like an auxiliary means of drawing the six bodies of cartography, in order to achieve more accurate positioning.
And once he has mastered the art of calculating distance and drawing directions, it means that Wei Guan should now be able to officially draw maps.
Of course, Liu Tan couldn't let Wei Guan go out to draw a map right away. The first task he gave Wei Guan was to draw a map of Shiheyuan.
When Wei Guan heard this order, he was so scared that he fell to the ground.
Shihe Garden is a royal garden, and it was given by the emperor himself. If he wants to draw a map, he must look at every place, even the most remote ones.
As we all know, royal nobles usually have some secrets that they don't want others to know. What if he discovers one of the secrets and is silenced?
Wei Guan was so frightened that he repeatedly declined. At first, Liu Tan didn't understand why he was so timid. Miao Rui couldn't bear it any longer and whispered, "Your Highness, Shi He Garden was built by His Majesty's personal order. It would be bad if he knew too much."
Liu Tan understood as soon as he heard it. After thinking about it, he simply sent Wei Guan to the farm. This time he did not let him draw the whole map. He asked him to draw the villages first, one village at a time. Except for his palace, he could draw every place, but he had to give him the finished map within ten days.
Wei Guan didn't understand why Liu Tan stipulated ten days, but he still took his bedding and ran to the farm to start drawing the picture.
However, in fact, it was because at this time, there were only ten days left before Liu Tan went to Wusun.
If Wei Guan's mapping fails to meet the standards within ten days, Liu Tan may really have to roll up his sleeves and do it himself.
Fortunately, Wei Guan did not disappoint his expectations. He finished painting a village in only five days instead of ten.
Of course, this is also because the drawing is relatively simple. Liu Tan did not ask him to draw a three-dimensional view. It is good enough if he can draw the top view clearly.
Wei Guan handed in his "homework" somewhat nervously. Liu Tan was quite satisfied after taking a look at it. The only problem was that the grid affected the visual experience too much.
No matter how thin the line is, it is easy to overlap with certain roads, rivers, etc. If you want to copy it completely onto another piece of paper, you don’t have the ability to make paper as thin as a cicada’s wing. This requires continuous improvement in technology.
Wei Guan couldn't help but feel a little frightened when he saw Liu Tan frowning. He was really worried that his map was not up to standard.
Liu Tan looked up and saw Wei Guan's frightened expression. He couldn't help but smile and said, "Well done."
Wei Guan's eyes suddenly lit up, and he looked at Liu Tan expectantly and asked, "So... am I considered a successful apprentice?"
Liu Tan nodded and said, "Of course, even if I were to draw, I wouldn't necessarily be able to achieve this level. I just find that the method of drawing squares doesn't seem to be very effective. There are too many lines, which can easily disrupt judgment."
Wei Guan immediately said, "I've basically mastered the relationship between size and proportion, so I can do it without a grid!"
Liu Tan shook his head. He couldn't expect everyone in the world to be like Wei Guan. This method must be promoted. Regardless of whether he could get maps from other countries, the Han Dynasty definitely needed its own maps.
Moreover, he was not afraid that the Huns would learn this method. Even if they could learn it, did they have paper?
Liu Tan held the paper and thought for a long time, and finally decided to start on the drawing board. He directly made a square frame with a wooden board, and then used thin lines to draw a grid in the middle according to the proportion, and then made a wedge so that it could be placed together with the drawing board. In this way, there was a grid as a judgment when drawing, and at the same time, the grid would not stay on it after the drawing was completed.
The only drawback is that there will be some ink missing in the areas with grids, but this lack can basically be ignored, and you can just add a few strokes when the time comes.
In order to make it easier to carry, Liu Tan's drawing board was not very big. He asked Wei Guan to draw one picture at a time and then piece them together into a complete picture.
Wei Guan looked at the things prepared for him and felt that Liu Tan had high expectations for him. It seemed that he didn't just want him to draw a map of Chang'an City. He couldn't help but ask, "Your Highness, what place do you want me to draw?"
Liu Tan said, "In two days, I will be leaving for Wusun. You will come with me and draw all the places you pass along the way. However, after you leave Yumen Pass, you will have to leave the group. I will send people to protect you and a guide to show you the way. I want you to draw a clear map of the road from Yumen Pass to Wusun. Wusun is not far from the Xiongnu, so you should try to get close to them and draw a map of that area as well."
Wei Guan never expected that Liu Tan wanted him to draw a map of the Western Regions. The road to Wusun was fine at the beginning, but when he heard that he had to go closer to the Xiongnu, he felt weak in the knees.
Wei Guan swallowed his saliva and said, "Your Highness, I...I am not capable of shouldering such a heavy responsibility."
Liu Tan looked down at him and said, "Don't you want to make a name for yourself? If you can draw this map, the Emperor will surely be delighted. I never treat anyone who has made a contribution unfairly. The Emperor might even meet you then. You will be the Han Dynasty's number one cartographer. Fame and fortune will be within your grasp, and all this will require you to take a small risk."
Wei Guan was slightly tempted. Liu Tan smiled when he saw him like this and said, "Besides, I want the map. I won't let you die, nor will I really let you go to the Xiongnu. I just want you to get closer. If there is any danger, my people will naturally escort you back."
Wei Guan lowered his head to think for a while, then suddenly raised his head and said firmly, "I will obey your Highness's orders!"
Liu Tan smiled and asked him to go down and prepare. After Wei Guan left, he recalled it and always felt that what he had just said seemed like a tempting villain.
But in fact, what he said was the truth. He finally had such a talented person, how could he let him die?
After asking Wei Guan to pack up his things, he continued to practice his riding skills.
These days he has been taking time to practice riding, but the progress is very slow. So far, he can only ride a horse for a walk. Once the horse starts running, he gets nervous. When he gets nervous, he can't help but use force with his legs, and when he uses force, the horse feels pain, and when the horse feels pain, it runs faster, and then he gets even more nervous.
This is simply a vicious cycle, but he has no way to stop it.
In the end, Li Buyan felt a little headache and simply said, "Otherwise... Your Highness can take a carriage after leaving Chang'an."
Liu Tan also wanted to, but finally made a difficult decision: "I have to wait until the next day to change the car."
This... is fine.
On the day of the wedding, Princess Danyang dressed up in red to bid farewell to the emperor and empress.
He didn't know if it was Liu Tan's illusion, but he always felt that Liu Che's face was expressionless and without any emotion. Chen Ajiao's eyes were slightly red, but she held on.
Liu Che's words of encouragement to Princess Danyang were merely official. Turning to look at Liu Tan, his expression became deeply concerned. "This journey will be a thousand miles, so you must be careful. I've sent the Imperial Chariot Commandant Huo Guang to accompany you. If there's anything urgent, you can discuss it with him."
Liu Tan was shocked when he heard this: "Why didn't you tell me earlier? How could such a great man go to the Western Regions? If something happens along the way, I can't afford the compensation!"
Continue read on readnovelmtl.com
