Regarding currency, Xu Ping's idea was to advance step by step towards paper currency in the capital, and to experiment with various auxiliary coins with it in the surrounding states and governments, and finally form a complete monetary system. Use new currencies to replace local iron coins in the country, etc. to complete the unification of currency and promote the completion of the national market.

The first step is to small iron coins, which delves the tentacles of the commodity economy to the countryside, connecting the scattered farmers with the large market across the country. The second step is to transition from shopping vouchers to paper money, accumulate experience, and change the thoughts of people at that time.

Thoughts are the most difficult to change. It is difficult to convince a person with your mouth, let alone convince many people. Xu Ping can only do it bit by bit with the least shocking method, waiting for the day when it comes naturally.

After talking about the situation of Xiaotieqian and the new tea law on Jingxi Road, Guo Zi said: "Deputy envoy, this time the subordinate officials came and went between Tangzhou and Ruzhou several times. They saw the former site where the Xianghan Cao Canal was dug decades ago, and it was abandoned there. It was a pity."

Xu Ping naturally studied this major project, and the three departments also managed the ditches. After listening to Guo Zi's words, Xu Ping said: "Of course, Cheng Neng only saw the benefits of opening the canal, but underestimated the difficulty of the project, and it would not be possible in the end. The mountains between Tangzhou and Ruzhou are continuous, which is one of the first things. Another way to connect the Huai River and the Yangtze River is to connect the Huai River, which is not that easy."

"In fact, Cheng Neng is not a whim and is empty talk. There is a pass between Tangzhou and Ruzhou, Fangcheng, and Dushui is very close to Lishui. It is only 10 or 20 miles apart, so it is not impossible to open a canal."

Xu Ping smiled and said, "Cheng Neng thought so back then, so he repeatedly assured Xiling that he would insist on opening the canal. I have also learned about the terrain there. The difficulty is not the canal that dozens of miles away, but the mountains that pass in the middle, which are the watershed of the South Han River and North Huai River. If the dam is started to lift water from south to north, there will be nowhere to leak water in the middle mountain. When the rainy season is continuous, the flood will inevitably blow the dam. Moreover, the dam collapses all and it will be out of control. He just opened the southern canal. In fact, the water supply in the north is average. Without major supporting projects, it will eventually fail."

"Xiaguan didn't think about it in detail. He just saw the ruins excavated that year and had already arrived at the Fangcheng Pass. He felt a little regretful. Just a few miles later, he would be connected to the water system in the north of the mountain."

Xu Ping shook his head: "It's not that a few miles away. Cheng Neng couldn't even measure the height of the terrain of each river back then. He thought about the water in the canal and then started the dam and shattered it. This matter involved a lot. When the three departments accumulated financial and material resources in the future, they could do it. Don't think about it now."

There is a remnant of Funiu Mountain between Tangzhou and Ruzhou. There is a pass in Fangcheng County. It has been a strategic location since ancient times. From the intersection of Jianghan area to the Central Plains, Chu State built the Great Wall here in the Spring and Autumn Period. The terrain of this pass is very low, and the two tributaries of the Han River and Huai River are very close here. Since the Han Dynasty, people have always wanted to communicate the north-south water system from here.

During the Taiping Xingguo period of Emperor Taizong, Cheng Neng, the transferee of Jingxi Road, wrote a letter asking to open a canal here to communicate the canal transport between the Han River and Ru River, and connect the two major water systems of the Yangtze River and the Huai River. As a result, when the canal was built to the Fangcheng Pass, heavy rain fell, destroying the dam built downstream, causing huge losses of personnel and materials, and the project was stopped. It was dug again ten years later, but it still failed.

The route of opening the canal this time is very reasonable. The South-to-North Water Diversion will still be chosen here after a thousand years, but the actual construction difficulty exceeds the limitations of the times.

There was no useful measuring instrument at that time. There was no idea about the elevation of each section of the canal and how deep the canal should be opened. According to the idea of ​​opening canals on a flat ground, the water depth could be opened by one meter. Because the terrain was too high and the water level could not reach the water level, the dam was used to increase the water level step by step. However, I did not expect that the mountains to cross in the middle were the watershed between the Yangtze River and the Huaihe River system. There was also the Yellow River system not far to the west. The hydrological situation was quite complicated and I had no ability to figure it out at that time. The method of using dams to lift water level was actually included in the watershed water into the canal. Once the flood season came, there was no way out, and it was almost inevitable that the dam was washed away.

To successfully open a canal in such a place, you must understand the local geographical and hydrological conditions. It is impossible to rely on hard work and hard work. The Bian River around Kaifeng Prefecture has connected the Yellow River and Huai River water systems, which has led to chaos in the water system. It is impossible to introduce the Han River water system without a comprehensive plan. It is impossible to make the surrounding area of ​​Kaifeng Prefecture a large depression that accommodates the surrounding water systems. In this way, even if the arable land in this area is completely abandoned, it is difficult to cultivate the farmland in Xu Ping's own farm.

The Yellow River and Huai River water systems in the Central Plains often fight. In some places, the basins belonging to them are ambiguous. It is very cautious to dig a new canal. When the canal guides water in, it must have a smooth route before guiding the water out. Otherwise, the groundwater water system is disordered and will affect a large-scale agricultural production.

Guo Zi didn't know much about the Xianghan Cao Canal. Seeing that Xu Ping had already gained an in-depth understanding and thought it was not suitable now, he would not talk about it anymore. It was indeed difficult to estimate the project situation.

Turning back, Guo Zi said: "In fact, what Xiaguan wants to say is not the Xianghan canal, but the Luo River entering the Bian River. This time, he went to Jingxi Road, and walked through the post road from Zhengzhou to Henan Prefecture. After passing Zhengzhou and entering Mengzhou, Xiaguan found that Biankou was not far from the Luo River entering the Yellow River. If the civil servants were recruited, the canal could be opened in a few months and the Luo River could be replaced by the Yellow River as the source of the Bian River. The Yellow River water was muddy and the Luo River was clear. After guiding Luo into Bian, it could save many civil servants who dredge the river channel."

Xu Ping was stunned when he heard this. He had never studied this project himself, and there was no trouble with water disorder in doing so. He just used the water from the tributary of the Yellow River to replace the water from the main stream, so that the Bian River will no longer be affected by the silt of the Yellow River.

After thinking for a while, Xu Ping asked, "This is indeed feasible? There is nothing important about the Qiaodaoxiang Army from Yongzhou now. If it is feasible, it will not take much effort to requisition the civilians of several states around it."

Guo Zi said: "Xiaguan went back and forth twice along the route, and checked clearly. There must be no obstacles to opening the canal. Moreover, there are many ponds along the way, so we can adjust the amount of canal water and not be afraid of droughts and less water in the Bian River. It is expected that if the canal is about 100 miles away, the clear water of the Yiluo River can be used instead of the Yellow River water into the Bian River, and we will no longer be afraid of sediment and sediment deposits affecting the canal transportation."

The current Bian River diversion from the Yellow River, which is closed in winter and opens again in spring. Due to the uncertainty of the Yellow River channel, the location of the Biankou where the water is diverted every year is not fixed, causing countless troubles. Moreover, the Yellow River has a lot of mud and sand, and the Bian River has to be dredged every year, otherwise it will affect the canal transportation. That's it. After passing the capital and before leaving the Kaifeng Prefecture, the Bian River has a bit of a hangover on the ground. The river water is nearly meter high above the ground outside the dike, and it is quite terrible once the dike breaks.

After thinking about it over and over again, Xu Ping said to Guo Zi: "You write a detailed note for me about this matter. I will go with you to read it along the way in a few days. If there is really no obstacle, you can build it. Now there is a bridge and road army here. They are the best at doing these things. It is best not to complete it before entering the scorching heat."

This project not only cleared the Bian River, but also communicated with the water transportation in Luoyang, which was indeed of great benefit.

(Note: The history of Luo’s entry into Bian was proposed by Guo Zi, but he died before the start of construction and did not reiterate his merits.)
Chapter completed!