Late Yuan Dynasty: I am the true emperor

Chapter 572 Innate Earth and Wood Sacred Body Xu Da
Just as land prices in several provinces south of the Yangtze River plummeted, forcing landlords to donate land to the imperial court, this year's mathematics special examination was proceeding in an orderly manner.

The complex application problem about blast furnaces in April was just a matter of whether or not one was qualified to officially participate in the Enke competition. To put it bluntly, it was a preliminary test, but even though it was just a preliminary test, many people were still eliminated.

Many scholars who were eliminated in the first round were naturally unwilling to accept defeat, feeling that the math questions were too difficult and that no one could possibly pass. Given the difficulty and the elimination rate, even if some math whizzes were to pass the exam, it was estimated that they would not be able to fill the 340 places required by the imperial court.

Moreover, even some of the candidates who passed the preliminary test gave very messy answers on their test papers. Many gave the result directly but did not provide the solution process. Some even drew a bunch of vertical and horizontal lines on their test papers, which is the traditional Chinese counting rod.

Regardless of the circumstances, as long as you can provide the correct answer, whether or not you have a solution process, you will pass this test and can go to one of the six test centers across the country to take the official exam.

Some people might ask, if you only give the answer and not the solution process, what if it was copied by cheating?
Lu Jin was indifferent to this, even if the answers were copied, because with math, you either know it or you don't, and the tests will get harder and harder in the future, so you'll be exposed sooner or later.

Even if you manage to pass all the tests by cheating, there will still be a placement test when you're assigned to a class. They might give you other test questions of the same difficulty that you can't answer? Heh, we can settle the score then.

As for those candidates who didn't even pass the preliminary exam, they naturally couldn't help but complain. However, at this time, the samples of primary and junior high school mathematics textbooks issued by the imperial court were distributed. At first, only one set was distributed to each prefecture, and then people from the counties under its jurisdiction were sent to the prefectures to copy them. The counties then distributed them to ordinary scholars. This was also at Lu Jin's request to distribute the mathematics textbooks first so that aspiring students could study at home.

Some scholars who already lived in the prefectural city had the advantage of proximity to the source and, upon seeing the set of elementary and junior high school math textbooks, immediately expressed their regret. Some even privately complained to the emperor, wondering why His Majesty hadn't distributed the books sooner, especially the geometric formulas. If they had learned those earlier, how could they not have calculated the volume of a biconical blast furnace?
Some people even drew out the double-cone blast furnace body from the exam question on the spot, and then recalculated using the formulas in the book. They quickly calculated the volume. When they then solved the application problem from the preliminary exam again, they found it very simple. Why didn't they think of that before? They were filled with regret.

Others looked completely bewildered because they suddenly realized that even though the textbooks provided formulas for them to apply, they still couldn't calculate them. This is because calculating the value of a cone requires the mathematical constant pi (π) of 3.14, but they didn't know how to use multiplication to calculate decimals. This was a problem because they hadn't even mastered the basics.

However, most people are still grateful for the set of mathematics textbooks passed down from the imperial court, because it is not only related to the special imperial examinations, but more importantly, it is really very practical.

Especially the lowercase numbers (Arabic numerals), various calculation symbols, vertical calculations, formulas, etc., this stuff is very practical and the calculations are very fast. Even if it's not for exams, it won't hurt for ordinary people to learn more.

The local officials also told the scholars who came to copy the books that once schools were built in various places and modern education was implemented, not only the special examinations, but also the regular mathematics examinations would test these subjects in the future. They also said that the questions in the special mathematics examinations would be more difficult than those in the textbooks, so everyone should prepare early.

Everyone gasped in shock. If it was even harder than that, who could possibly pass the exam?
However, Lu Jin didn't care about that. The reason why the questions were so simple this time was because most of the scholars in the country had not studied mathematics. Once mathematics education was widespread, how could such simple questions still be given?

To put it bluntly, the mathematics special subject he created wasn't for ordinary people, but specifically for geniuses. You should think of this mathematics special subject as a science competition in later generations; it's not a regular college entrance examination.

The mathematics education system of the new China was designed by Hua Luogeng, and Qian Xuesen also suggested shortening the school system.

Qian Xuesen believed that a person's intellectual peak is at the age of 20. Therefore, in order to make full use of this advantage, children should start school at the age of 4, finish primary and junior high school at the age of 8, graduate from university at the age of 16, then have a year of internship, a year of professional study, graduate with a master's degree at the age of 18, and graduate with a doctorate on average at the age of 20.
Although, in the end, this suggestion was partially adopted. Of course, this method of cultivating geniuses could not be fully popularized, but it still left a way for those geniuses to advance. This is the system of "skipping grades", "competitions", and "gifted youth class".

The special examination organized by Lu Jin was actually another way to select geniuses, in addition to the formal imperial examination system. Therefore, the exam questions would naturally become more and more difficult. Moreover, after the popularization of education, the special examination would not only test mathematics, but also physics and chemistry.

Therefore, when everyone heard that the formal imperial examination for mathematics would also test the content of these textbooks, and that the special examination would become increasingly difficult, someone immediately suggested that they form several mathematics societies, which were actually self-study mutual aid groups.

The imperial court has only issued textbooks, allowing scholars to copy and study them on their own, but there are no professional mathematics teachers to teach them. Moreover, most scholars have varying levels of mathematical understanding. The best solution at this time is to establish private learning societies where everyone can gather together to study, exchange learning experiences, and whoever understands the contents of the book first can then teach it to others.

Besides, there are relatively few books now, so those who didn't have time to copy the textbooks can copy them at the school in the future, instead of having to keep running to the government to copy them.

As soon as these words were spoken, many people responded immediately, and mathematics societies sprang up all over the country. When some private schools and academies owned by gentry and wealthy families heard the news, they also sent people to the government to copy the books and then take them to their own academies and private schools to teach their children.

Some booksellers saw a business opportunity and first obtained samples from the government, then reprinted the textbooks and sold them everywhere. When selling them, they claimed that these were the designated textbooks for the imperial examinations in the future, and for a time, sales were quite good.

Meanwhile, while the provinces south of the Yangtze River were busy establishing mathematics societies and recruiting immigrants, the immigration project in the north was also not stopping.

It is worth mentioning here that although Lu Jin and the historical Zhu Yuanzhang both promoted large-scale immigration, their overall immigration policies differed significantly.

The situation in the south was largely the same, with immigrants moving from the most populous regions, Jiangxi and Hubei, to places like Sichuan, Yunnan, and Guizhou. However, the immigration policies in the north were quite different.

The two most populous provinces in the north are Shanxi and Shandong, with a combined population of over ten million. Historically, Zhu Yuanzhang mainly relocated the population of Shanxi and Shandong to Henan in the Central Plains, and also some to Hebei. This was a migration from the outer border areas to the center. However, Shandong did the opposite, relocating the population from the border areas to the outermost areas, leaving Henan relatively empty.

For example, this year, the north also sent ten divisions, totaling 135,000 people. Among them, Shanxi sent four divisions, three of which moved to the Hetao region and one to Xilin Gol in southern Inner Mongolia; Shandong sent three divisions, all of which moved to Liaoning, Jilin and other places; Jiangsu also sent three divisions, which moved north along the Grand Canal to the Grand Canal in Hebei.

In this timeline, apart from the Central Plains Campaign when Lu Jin moved five agricultural reclamation divisions there in one go, no population has been migrated to Henan since then. Therefore, Henan is still sparsely populated.

This is where the overall strategy differs.
In the original history, because Zhu Yuanzhang let Xiao Tieguo escape, the Ming Dynasty was constantly facing the counterattack of the Northern Yuan. In addition, Henan was already overgrown with weeds and nine out of ten houses were empty due to natural disasters and wars. Therefore, Zhu Yuanzhang decided to relocate people from the border areas to populate the Central Plains, while building high walls and storing grain in the border areas to build the northern border defense and prevent the Northern Yuan from moving south again.

During this process, Xu Da practically transformed into a natural-born master of civil engineering, working himself to the bone to build cities in the north. He not only created the Shanhaiguan Fortress defense system that would later become famous throughout the world, but he also scaled down and reinforced the capital city of Beijing. He even built Datong and Taiyuan in Shanxi into impregnable fortresses, to a level of absurdity that gave the attacking side a real headache.

However, one point needs special attention: the Hetao region.

The Hetao region is where the Yellow River bends northward. Here, the Yinshan Mountains to the north protect it from the cold air of the grasslands and the sandstorms of the desert, while the Helan Mountains to the west also provide shelter, creating a plain nestled between mountains and water. Based on its natural geographical layout, the Hetao region can be roughly divided into three areas: the Qiantao (Hohhot, Baotou, etc.), the Houtao (Bayannur region), and the Xitao (Yinchuan Plain) adjacent to the Helan Mountains.

The temperature and latitude here are similar to those in Liaoning, so theoretically it is suitable for farming. However, the rainfall is a bit low. According to the later geographical standard that 400 mm of annual precipitation is suitable for farming, none of these three places meet the standard for farming.

The best-condition areas are the former (Baotou and Hohhot) regions, with an annual precipitation of 300 to 350 millimeters, barely reaching 400 millimeters. However, the western Yinchuan Plain and the rear Bayannur region are much worse off. The Yinchuan Plain has an annual precipitation of only about 200 millimeters, and Bayannur is even lower, with only about 150 millimeters.

However, all three areas have water from the Yellow River for irrigation, which solves the problem of water for farming, so these three areas are indeed suitable for cultivation.

In particular, the Qiantao region was incorporated into the territory of the Zhao state during the Spring and Autumn Period. The Zhao Great Wall was built on the Yinshan Mountains. The Han Dynasty also established the Yunzhong Prefecture here. It has been known since ancient times as the "Jiangnan beyond the Great Wall" and "the Yellow River brings a hundred harms, but only benefits the Qiantao region".

However, in the early Ming Dynasty, Zhu Yuanzhang never managed this land. He only established Dongshengwei at the border of the Hetao region closest to Shanxi, and then never paid any attention to the Hetao region again, leaving it to its own devices.

As a result, the Hetao region was later occupied by the Mongols. Altan Khan initially grazed his livestock in the Houtao (Bayannur region), and later he went further to the Qiantao (Hohhot) region. He also recruited Han Chinese refugees and displaced military households to farm in the Hetao region, and the taxes he collected were even lower than those of the Ming Dynasty, so many people from Shanxi took the initiative to go and seek refuge there.

At the same time, he recruited a large number of Han Chinese artisans to start handicrafts to make weapons and armor. He even built a city in Hohhot, which was initially called Guihua City. In the late Qing Dynasty and early Republic of China, it became Suiyuan. In the People's Republic of China, it became Hohhot. In other words, the predecessor of the city of Hohhot was established by Altan Khan.

After this fellow occupied the Hetao region, he indeed caused a great disaster during the Jiajing era. The two sides disagreed over the tribute issue, and Altan Khan directly sent troops to Datong, threatening the Ming Dynasty to open up trade. As a result, the general of Datong bribed Altan Khan and asked him to attack another place. So this fellow went to Gubeikou and broke through the pass, besieging Beijing. He looted the area around Beijing for eight days, and the Ming Dynasty was forced to agree to a treaty under duress and agree to open trade. This event is known in later generations as the Gengxu Incident.

This incident clearly demonstrates the importance of the Hetao region to the northern defense system. If you don't control this area, it will naturally fall into the hands of the Mongols. Putting the enemy so close to you is obviously not a good thing.

However, Lu Jin couldn't understand why Zhu Yuanzhang had neglected the Hetao region and instead set up nine border guards. He had placed three of his sons in Xuanfu, Datong, and Taiyuan in Shanxi, creating a series of defense zones. He even placed two more sons in Gansu and Ningxia.

However, the Hetao region was the only exception. The Qiantao, Houtao, and Xitao (Yinchuan Plain) areas were all excluded, completely excluded from the Ming Dynasty's northern defense zone. It's absurd that such an important region as the Hetao was abandoned by Zhu Yuanzhang.
Lu Jin couldn't understand Zhu Yuanzhang's thought process, so he simply stopped thinking about it. What Zhu Yuanzhang didn't want, he wanted.

So ever since the Northern Expedition destroyed the Yuan Dynasty and recovered southern Mongolia, Lu Jin had been continuously migrating people from Shanxi to the Hetao region. In Lu Jin's view, Henan was the heart of the Central Plains, and now that southern Mongolia had been taken over, and the Guanzhong region of Shaanxi was also under the control of the Ming Dynasty, there were no enemies around Henan. Therefore, the priority of migration was not high.

Anyway, the meat will rot in the pot, and the land can't just grow legs and run away. Henan is a well-connected place connecting ten provinces. Even if no one migrates to Henan, it can recover slowly in the future thanks to the population gathering effect of the Central Plains. But if you don't take care of places like Hetao and Inner Mongolia now, they will really be gone in the future. This is the difference between Lu Jin and Zhu Yuanzhang's immigration strategies.

Currently stationed in the Hetao region is the 119th Division of the 47th Army, led by Xu Da. In this timeline, Xu Da also displays his innate talent for civil engineering, leading Shanxi immigrants in a frenzy of city building in the Hetao region.
In this timeline, Lu Jin successfully launched a northern expedition in the first year of the founding of the Ming Dynasty. The following year, the country began to relocate people to the Hetao region. The first migration involved three divisions. According to the old system of three regiments under each division, one regiment was equivalent to one county, and the three divisions were equivalent to nine cities.

Therefore, in just one year, Xu Da led the immigrants to occupy the entire Qiantao region, and built two prefectural cities and three passes in Qiantao. Among them, a new city was built in the location of Hohhot in later generations, which was named Yunzhong Prefecture. Of course, these new cities are still only rammed earth structures and have not yet been covered with bricks.

Regarding the location of the city, it was not entirely a coincidence. Hohhot's location was not only adjacent to the Dahei River, which facilitated agricultural irrigation, but also had a valley in the middle of the Yinshan Mountains to the north of Hohhot, which led directly from the Qiantao area to the grasslands north of the Yinshan Mountains. This mountain pass was later called "Shirdeng Pass".

In other words, since the front of the Hetao region can reach the grasslands north of Yinshan through this mountain pass, the enemies on the grasslands can naturally also enter the Hetao region through this mountain pass.

Therefore, Xu Da, like Anda Khan, chose to build a city here. Anda Khan mainly did so for convenient transportation, while Xu Da built a city nearby to block the mountain pass.

He not only built a new Yunzhong Prefecture, but also constructed a small pass at the location of Shildeng Pass, named Qingyun Pass. Behind the pass, a new county called Qingyun County was established. The name is a straightforward geographical name, meaning the county that faces Yunzhong Prefecture through the gap in the Daqing Mountains.

Although Qingyun Pass is small, it is exceptionally sturdy. This small pass effectively controls the mountain pass. In the future, a group of internal guards will be trained from among the immigrants and stationed here for a long time, so there will be no need to worry about enemies entering the Hetao region from here.

In addition to Yunzhong Prefecture and Qingyun County, the Yuan Dynasty originally had three county seats on the east side of Qiantao, namely Dongsheng Prefecture, Yunnei Prefecture and Feng Prefecture. These three counties were also retained by the Ming Dynasty of Lu Jin.

Now, three more counties have been added: Zhonggu County (Dalad Banner), Wuling County (in memory of King Zhao Wuling), and Heihe County (on the banks of the Heihe River). This brings the total number of counties in the former Tao region, excluding the area surrounding Baotou in later generations, to eight. Each county currently has only 4500 people, the size of a regiment. In the future, more women will be moved here to breed and multiply, and the population will soon increase.

Zhonggu County is located in a narrow area formed by the western foothills of Daqing Mountain and the Yellow River. The narrowest point where the mountains and the river meet is only five or six miles apart, making it very suitable for building a pass. If a city wall is built here, the main passage between the rear and front areas can be blocked. In this way, even if the enemy attacks from the rear area (Bayannur), the pass here can hold them off for a while, buying time for reinforcements to be dispatched from the rear.

So Xu Da built a fortified pass here, named Zhonggu Pass, meaning the most fortified place in the middle of the front line. The pass was called Zhonggu Pass, and Zhonggu County was located to the east of the pass. In the future, the people here could be used to guard the pass nearby.

Then, after passing Zhonggu Pass and continuing west, you will reach the Baotou region of later generations. Xu Da also built a new prefecture city in the location of the later Baotou, named Jiuyuan Prefecture, which, like Yunzhong Prefecture in Hohhot, was a restoration of the ancient place name.

In addition, Wu'an County was newly established to the east of Jiuyuan (Baotou). To the west of Jiuyuan, at the junction of the Qiantao and Houtao areas, which is also the narrowest point between the Wula Mountains and the Yellow River, Xu Da built Xisheng Pass here, corresponding to Dongsheng County in the far east. To the east of Xisheng Pass, Xisheng County (Urad Front Banner) was newly established. Between Xisheng County and Jiuyuan, Wuding County was also newly established. In total, one prefecture and three counties were added around Baotou, including Baotou itself.

Thus, in just one year, Xu Da controlled the entire Qiantao region (Hohhot, Baotou, etc.), adding nine new county seats. Combined with the original three counties, the entire Qiantao region had a total of 12 counties from east to west, as well as three passes, basically stabilizing this arable land in the border region.

At the beginning of this year, three more divisions of new immigrants set off from Datong, Shanxi, heading west through the Xikou (Shahu Pass) towards the Hetao region. Xu Da led them westward from Xisheng Pass. Now that the Qiantao region was almost full, he wanted to lead this group of immigrants to continue to occupy the Houtao (Bayannur) region, where he would establish nine new counties and restore the rule of Shuofang Commandery over the Houtao region during the Western Han Dynasty.

Use fortress tactics, filling the entire Hetao region city by city!
(End of this chapter)