Dams are not something you can build if you want to, and if you don't do it well, it will cause huge damage to the ecology.

Weishui is seaworthy, but the water level of Weishui is not deep, otherwise, it would not have dried up and stopped flowing in the past few years.

Building a dam inevitably re-divides the water level of Weishui, and with plains on both sides, the biggest problem is that if a dam is built, it is possible to backflow the river.

The second is that after the dam is built, ships on the Weishui River will not be able to navigate.

The upstream of the dam is at most up to the dam, and the downstream is not accessible to boats at all.

Therefore, a peerless project like the Three Gorges cannot be carried out by itself, and there is no condition to do it here.

"Extend outward, dig a new channel, then dig a reservoir, store water on it, and set up a dam at the other end, with the front coming in and the rear returning." Li Yuanji took advantage of the situation to draw a simple diagram on the ground.

If the river can't be cut off, then build a reservoir, as long as it is set up properly, its efficiency is not much smaller than building a dam directly in Weishui, and more importantly, it will not destroy the ecological balance, let alone cause ships to be unnavigable.

But in any case, it is obviously unreasonable to want to do some earth-shattering project in ancient times, and there are not so many opportunities.

When there is no heavy construction machinery, all the work can only rely on manual digging a little bit, a hook machine can dig a few times, and an adult laborer needs to work for a day to catch up.

In such an era of extremely low efficiency, it is obviously not particularly appropriate to rely on manual digging of reservoirs.

Anyway, if this project really starts, 10,000 laborers, to say the least, will have to work for a year to barely complete.

And the further down the soil goes, the more laborious it becomes, and sometimes you will encounter stones or something, which is even more difficult.

Fang Xuanling pursed his lips, thought about it for a while, and finally spoke: "Your Majesty, this method is also inappropriate, if it is not good, when a few canals and reservoirs are completed, the railway will be paved to Luozhou." ”

"I'm just proposing an idea, you can use your imagination to see how to solve this problem." Li Yuanji put on a disgusted expression, is it really appropriate for you to dismantle the stage like this?

Fang Xuanling's face was embarrassed, and he knew that he wouldn't speak.

Li Yuanji is infinitely missing the electricity of the future, that's really a good thing, it's a pity that he doesn't have anything, as for the steam engine, the principle is proposed by himself, although he doesn't understand it, but the general direction is right, a few laymen are studying it in confusion, who knows where it has been?

Next, Li Yuanji personally watched the whole process of making the rails.

First, the iron ore is made into molten iron with high-quality coke and the latest improved blast furnace, and then some other raw materials are added to make it further refined, and after many repetitions, it becomes molten steel, and then it is poured into the abrasive, and the preliminary shape is set, taking advantage of its heat, it first enters a coke oven and continues to heat it to keep its temperature not lowered, but it will not melt.

The other end is put into the hydraulic stamping machine, powered by the river water, constantly turning the gears little by little, the original shape of the rails that have been stuck, step by step is squeezed step by step, through more than 50 gears, and finally made into shape.

There is no need for manpower to push, what people have to do is just to put the rail on the press at the very beginning, and then it's OK, the hydraulic force drives the gear, and the gear will drive the rail to go forward automatically.

The process of making rails is not complicated, but the simple process also indicates that the quality cannot be superior, but in any case, the horse-drawn train is still no problem.

A section of steel rail is about 20 meters long, which is already the limit, and even dozens of people need to move it together.

In this era where everything depends on hands, it is actually good to be able to do this.

"Continue to increase investment in the academy!" Before leaving, Li Yuanji commanded Fang Xuanling with a feeling in his heart.

Technology changes life, and I have not really realized the meaning of this sentence until now.

Different from the era of the fart people in later generations, now it is completely different feelings.

Although today's these, in the current era, have proved that Datang's technology and other means are far superior to others of the same era, but this is far from enough.

Li Yuanji's requirements are not high, according to the current progress, it is enough to make Datang's industrial level reach the level of the early years of the Republic of China in his lifetime.

Talent is the most important thing.

Professional things are done by professional people, and Li Yuanji does not interfere too much in too many things.

But even so, for Li Yuanji, this emperor is also very tired, so tired that he wants to pick a son.

But the son below is still so young, and even if he gives way now, there is no one to take over, so he has to stay in this position for a long time.

……

To the west of Chang'an City, a huge team is slowly advancing.

This team is mixed, and there are many people who are dressed differently, but the leader is the Tang people, and they are also equipped with the Tang Army to protect the whole process.

The whole team is large and small, adding up to more than 500 vehicles, so large that people feel spectacular when they see it.

It's just a pity that along the way, in addition to the fatigue of the long journey, these people inevitably have some disappointed expressions on their faces.

All the way from the Western Regions, I have experienced a lot of cities on the way, most of these people have traveled to and from Chang'an, and they have also seen those cities, but every time they see them, they are more dilapidated than the last time they saw them.

Although this is only a superficial phenomenon, it is undeniable that Datang's national strength has indeed decreased a lot.

Gaochang Wang Lu Wentai dared to provoke the Tang Dynasty, which was nothing more than a trip to Chang'an and saw the current situation of Chang'an, so he was relieved and bold to dare to hook up with the Turks.

Although the Tang people slapped him in the face with facts, who knows what is inside?

Although disappointed, they don't have the courage of Lu Wentai, even so, they still don't dare to have any contempt for the Tang Dynasty, the 50,000 army is in the Western Regions, even if they are united, they are by no means the opponent of the Tang Army.

What does 50,000 Don troops mean? It means that if the Turks do not fight with all their strength, these 50,000 Tang troops are enough to sweep the entire Western Regions.

"Ahead is Chang'an, the envoy has already sent someone to inform you, you can rest tonight." Wang Xuance pointed to Chang'an City, which could be seen faintly in front of him, wiped the tiredness on his face, and said with a smile.

Changan? It's just bigger, and it's not much more luxurious than other places.

This point has almost formed a concept in everyone's hearts, but it is also undeniable that the cultivated fields that can be seen everywhere along the way still make them envious.

In the Western Regions, this kind of scene is impossible to see, and the Western Regions are short of water, so it is doomed that farming cannot be a long-term solution, and can only rely on grazing to live.

In fact, after the influence of the Central Plains Dynasty, the life of the Western Regions has gradually changed, from the beginning of grazing to the combination of agriculture and grazing.

At the gate of Chang'an City, officials from the Ministry of Rites came to receive them, but in order to show the prestige of the Tang Dynasty, the Ministry of Rites and the Waiter did not appear, but were greeted by the main guest of the Ministry of Rites.

It's not that Datang looks down on these people, but it's not necessary.

Although the Tang Dynasty is not as strong as the national strength of the former Sui period, compared to these countries in the Western Regions, it is still a behemoth, and it is still not something they can provoke.

Moreover, today's Datang is no longer the Datang in the early years of the founding of the People's Republic of China, and the Datang every day is constantly improving.

Therefore, Datang has the capital to look down on them, and has the courage to let a host and guest from the five grades to receive them.

With a simple shudder, the Ministry of Rites officials led this huge team to Taipingfang.

It has become the reception center of Datang, as the most luxurious and prosperous place in the whole Chang'an, and it is naturally a good window for Datang to show to the outside world.

Abu Adu frowned deeply since he entered Chang'an, and remembered that the last time he came to Chang'an, the crowd here was not so dense.

Of course, density is only one thing, and I always feel that the people here are different from what I saw before.

But where is the difference, Abu Adu is difficult to compare for a while.

In short, the prosperity of Chang'an is completely different from what they see on the surface.

"This ...... Why are there so many people here? About to enter the Taiping Fang, Abu Adu couldn't hold back any longer, and pulled the Ministry of Rites official next to him and asked.

The feeling of the Taiping Fang is completely different from other places, the brand new houses and courtyard walls, and even before he enters it, he already feels that it is definitely another paradise.

But shouldn't the Ministry of Rites find a better and quieter place to receive them?

"Hehe, Taipingfang, as a Li Fang built by His Majesty himself, now integrates commerce, diplomacy and economy, and at the same time, it is also the location of the reception of the Tang Dynasty, which has the most luxurious hotel in Chang'an." The official said with a smile, contemptuous in his heart, and secretly said You dirt buns, don't you know what the hotel is? Speaking out scares you to death......

These guests from the Western Regions were observing, and many people were also observing them.

However, unlike the guests of the Western Regions staring at one place for a long time, the people just glanced at it casually, or looked at it twice, and then they would go about their own business, and no one would stay on them for too long, which also made Abu Adu very curious and strange.

Of course, they know the treatment of foreign countries in Datang, even if they don't know anything, no one dares to ask more now.

Everything is inferior, only the Tang people are high.

This is not just a bluff, if you are not convinced, you can give it a try and see what the results are.

However, the earth bun is the soil bun, and the moment they entered the Taiping Fang, including Abu Adu, all the guests from the Western Regions were stunned, and they had never seen such a luxurious place......