Liu Che was a little surprised when he received Liu Tan's letter. It had been more than seven days since Liu Tan last wrote back. Calculating the messenger's pace, it could even be said that Liu Tan sent two letters almost one after the other.

He remembered that the last time such a thing happened was when the Xiongnu Left Commander sent an envoy to request internal and external assistance to kill the Chanyu Wu Shilu, but Liu Tan wanted to kill first and report later.

Thinking of this, Liu Che's expression suddenly became a little subtle. Although he was very happy that his son wrote to him, but...even Liu Che couldn't bear it if something happened all the time.

The bottom line is that the Han Dynasty had too little control over the Western Regions, and Liu Che felt that he was out of reach of everything that happened to Liu Tan there.

Liu Che was already middle-aged and had been emperor for so many years, and there were not many things that could make him feel this way.

So he looked at the letter on the desk, stared at it for a long time before slowly opening it.

Then I was almost broken by the first sentence.

Originally, Liu Che was leaning on the back of the throne and reading slowly, but when he saw the first sentence, he sat up straight and his eyes were fixed on the gold mine.

He suddenly remembered that he had just mentioned that a huge box was delivered along with the letter.

Liu Che originally thought that Liu Tan had found some beautiful stone, or some local specialties and sent them to him, but according to what was said in the letter, it might be a huge gold nugget!

Liu Che turned to Bu Fan and ordered, "Go and get the box that Tan'er brought back, and by the way, call over... the Shaofu."

Liu Che originally wanted to ask Bu Fan to call the Grand Minister of Agriculture, after all, such matters should be handled by the Grand Minister of Agriculture, but after thinking about it, he decided to ask someone to call the Minister of the Imperial Household.

According to the laws of the Han Dynasty, any gold mine discovered must be nationalized, but there is one group that is an exception - the royal family.

After all, the whole world belongs to their family, and no one can say anything if Liu Che wants to take the gold mine for himself.

Bu Fan immediately had the box delivered, and at the same time asked someone to call the Shaofu over.

The box arrived faster than the Shaofu, and was opened in front of Liu Che. The dog-head gold simply placed inside was shining with dazzling light. Liu Che was also a worldly man, but dog-head gold was very rare. Even if it was not pure gold, its charm was hard to resist.

This one point alone was enough to make Liu Che like it - it was naturally formed.

Liu Che examined it carefully for a long time and suddenly said, "Does this piece of gold... look like a horse's leg?"

Bu Fan bent down and said, "It does look like a horse's leg."

Liu Che was delighted: "Good, good, this is a warning from heaven. The envoys we had previously selected to be sent to Dayuan can now set off."

Liu Che had always been obsessed with the Ferghana horses. He had already selected the envoys to go to Dayuan, but he had not let them go because he wanted to wait for Liu Tan to come back and inquire in detail about the situation in the Western Regions.

But now Liu Che estimated that his son might not be able to return in the short term. What's more, Liu Tan also sent someone to deliver a newly drawn map of the Western Regions. Although it was not complete, considering that the map came back early because the situation was urgent at the time, Liu Che would not be too harsh on him.

Bu Fan immediately went down to pass on the order. At this time, Shaofu Ji Hang came quickly, saluted Liu Che and said, "Your Majesty, I pay my respects to you."

Liu Che said, "Tan'er has discovered a gold mine in the Western Regions. The extent of the mine is unknown at this time. You should quickly select experienced individuals to go to the Western Regions to assist the Fifth Prince in mining."

The Shaofu was still wondering why the emperor suddenly summoned him. The vernal equinox had passed and the summer solstice was still far away. There were no major festivals that required the Shaofu to be busy.

Then, he was caught off guard by Liu Che. After hearing this, his brain was a little slow to react. He was stunned for a few seconds before stammering, "Fifth...Fifth Prince...discovered a gold mine?"

Liu Che admired Ji Hang's bewildered expression, and finally felt more at ease. He nodded and said indifferently, "Tan'er is lucky, but the location is a bit remote, so it's best to choose someone quickly."

Ji Hang responded woodenly. After he left the hall and was exposed to the sunlight outside, he finally reacted and gasped.

A gold mine was discovered in the Western Regions. What is the Fifth Prince going to do?

There are very few gold mines exposed on the ground. According to His Majesty's instructions, it is speculated that they were not discovered from the ground, otherwise we could have judged a little by looking at the ground. So...did the Fifth Prince go to the Western Regions to dig deep into the ground?

Ji Hang left with a heart full of doubts.

Liu Che was still admiring his horse leg gold. Well, even though Liu Tan called it dog head gold, Liu Che still stubbornly thought it was horse leg gold. This was God's sign that this trip to Dayuan to exchange for the Ferghana horses would be very smooth.

After admiring it, Liu Che began to think about what to do with this gold mine.

Liu Tan had actually written it very clearly before. The city was built mainly for this occasion, and the reason why it was built so well was because he thought the Han Dynasty might need it in the future, so there would be no need to build a city temporarily. What's more, if everything went well, it would not be a problem to station troops there permanently in the future.

Liu Che had basically never thought of sending troops to stay there permanently. The place was too close to the Cheshi Kingdom and too close to the Xiongnu. It was even closer than the Surrender City and was really unsafe. The Han army could not reach there now, otherwise it would not have allowed Liu Tan to seek refuge in Xiao Wusun first.

But the gold mine... After Liu Che weighed it in his mind for a while, he felt that it still depended on how Liu Tan fought this battle.

If we can scare the Jie State and intimidate the Cheshi State so that it does not dare to ask the Xiongnu for help, then we can send people to garrison there. If not, we must withdraw.

Liu Che decided to mine first, and dig as much as he could. If not, he would destroy it and not let the people in the Western Regions know!

Then he became a little worried, as he always felt that Liu Tan's painting style was different from that of others.

He had previously said that Liu Tan was like Wei Qing, but now he felt he needed to take that back.

Back then, Wei Qing was quick to act and said he would fight. His goal was very clear, and his actions were very swift. But when it comes to Liu Tan, he said he would fight a long time ago, but what is he doing now? He's still building a city!

For a moment, Liu Che didn't know whether to send troops to continue supporting, so he could only order Yangguan to pay attention to support at all times. As for mobilizing a large number of troops... forget it for now. Once the soldiers are moved, the military expenses will be sky-high. Now the finances of the Han Dynasty can't support it. As for Liu Tan paying... forget it. How can his little money support the army to go to war?

Liu Che was happy at one moment and sad at another.

Liu Tan had no idea that he had caused Liu Che a lot of trouble. After learning that Liu Che had sent experienced craftsmen, he began to build the city with confidence again.

After designing the underground sewage problem, Liu Tan went to the construction site to take a look.

At this time, the construction site is driving the pile foundation bit by bit. Because there are many rocks and the land is not flat, the pile foundation cannot be standardized and all the same. As a result, the length can only be designed according to the terrain to ensure that the ground of the city is absolutely flat.

Because of the tents providing shelter, many large braziers were burning inside the construction site for lighting.

Even though the temperature in the Western Regions was not as high as in the Central Plains, Liu Tan was still feeling very hot in what could be considered an enclosed space.

He stood there and looked around, feeling that the scene was familiar and particularly close and familiar. After thinking carefully for a long time, he suddenly realized that this was what an archaeological site in later generations would look like.

In later generations, rescue excavations would be covered with a shed to protect cultural relics, and now they have a bit of that feeling here.

Not only did Liu Tan see such photos when he was looking up information, he even went to the archaeological site to join in the fun. It would be strange if he was not familiar with them.

After checking the progress, he casually glanced at the corner of the tent and found a lot of bedding. He couldn't help but look at Jiang Chong and asked, "Are you asking everyone to work day and night?"

Jiang Chong followed Liu Tan's gaze and saw the blankets. He now knew Liu Tan's personality and said immediately, "A lot of people sleep here at night. It's been very windy and dusty these past few days, and many people think it's safer here than in tents."

How can it not be safe? So much wood is used to make the frame, and the piles are driven very deep. The whole tent is almost as sturdy as it can be. If it really encounters wind and sand, its stability will definitely be stronger than a small tent.

Liu Tan was somewhat helpless: "This is not a place to sleep. I know it's crowded now, but I have to tell them that this tent is not foolproof. If it collapses, a regular tent might give you a chance to escape, but if these wood falls down, the bumps and bruises might kill you."

Jiang Chong whispered, "Your Highness, the wind and sand can blow this tent over. Even if someone survives, they will probably be in great danger after getting out."

They had witnessed how terrible the wind and sand in the Gobi Desert were. Once, the reins of a horse were delivered but not tied. When they looked for it the next day, there was only a horse carcass left in the sand.

It is said that this is the case when you are lucky. If you are unlucky, if you fall into quicksand, you will never see your body again.

After hearing this, Liu Tan didn't say anything else. This broken place would be unsafe as long as a house was not built.

So he was particularly anxious now. After walking around, he turned back and started thinking - how to build sewage facilities?

Underground drainage can definitely make the city cleaner, but there is a very serious problem with underground drainage, which is how to build the drainage pipes?

He now does have cement, a killer weapon that transcends time and space, but the problem is that it is still very difficult to shape cement into pipes.

The biggest problem is that there is no model. It would be inappropriate to ask someone to do it now. Moreover, their means of transportation are very primitive. If the drainage pipe is too large, it cannot be transported here at all.

Liu Tan sat there thinking for a long time, and finally found that there seemed to be only one way - to use cement as an adhesive to glue the stones together to form a round pipe shape.

In this way, they can build it bit by bit directly in the place where the pipes need to be laid, but the operation is quite difficult, because the stones they have now are basically all dug out from the ground, and there was no regulation on the shape when they were dug, so they are of different sizes and shapes.

It is extremely difficult to put these unshaped stones together to form a circular pipe and ensure that it is leak-proof.

Liu Tan sighed, fiddling with the sand in his hands while wondering whether Huo Guang would beat him up if he made this request.

After all, Huo Guang has become visibly thinner since he followed him on the diplomatic mission to the Western Regions. If this continues, he wonders if the Huo family will think that he has abused Huo Guang after they return to Chang'an.

When Huo Guang came in, he happened to see Liu Tan building a miniature city bit by bit with bricks, stones and tiles.

Of course, this city now only has the foundation, which looks similar to their current progress, but in fact, if you look closely, you can see some circular tubes interspersed between the piles.

Huo Guang felt a sinking feeling in his heart when he saw his sad face. He was really afraid of Liu Tan's expression.

Generally speaking, when Liu Tan shows this expression, it means that he has encountered a problem. After encountering the problem, what Liu Tan can think of and what solutions he can come up with are basically completely uncontrollable.

Huo Guang first put down what he was doing and asked, "Your Highness...what difficulties have you encountered?"

Liu Tan was lying on the desk in a very ungraceful manner at this time. He did not sit up when he saw Huo Guang coming. After all, they were already very familiar with each other, and Huo Guang probably could accept his unkempt sitting manner.

He looked up at Huo Guang and said, "How do you think we should lay these pipes?"

Huo Guang had grown accustomed to the new words that popped out of Liu Tan's mouth from time to time and had become immune to them. In fact, this was not the point. He quickly asked, "Your Highness, if you have any difficulties, please speak directly."

Don't come up with something new just by thinking about it.

After Liu Tan explained the difficulties, Huo Guang said decisively, "That's no problem, Your Highness, don't worry."

Compared to Liu Tan's troubles, these are all trivial matters.

Liu Tan looked at Huo Guang with some doubt: "Really? But...how can we guarantee that these broken stones will be round? How can we guarantee that they will fit together perfectly? How can we..."

Huo Guang took a deep breath and said, "Your Highness, please don't worry about this!"

Liu Tan blinked and decided to trust Huo Guang. After all, Huo Guang was really capable and would not make a promise easily if he was not sure.

However, in reality, even a gentleman like Huo Guang could not help but learn to lie when facing Liu Tan, and he had no psychological burden.

He really couldn't accept Liu Tan's sudden whim. Otherwise... he should have returned to Chang'an by now!

However, Huo Guang really did not lie to Liu Tan. The wisdom of the ancient people of Huajia should not be underestimated. After all, there was no clear scientific system in ancient times, but they were once the world leader in various inventions and creations.

On the third day after Liu Tan started to worry, the wise masses came up with a solution - it didn't matter if there was no model, they could make the core.

Anyway, they needed a round tube that was hollow inside, so they simply found two people who were not yet completely dried to hug the tree, peeled off the outer bark completely and covered the wood with it, and then paved the outside of the tree little by little with stones and cement.

The main reason why it must not be air-dried is to ensure the integrity of the bark, so that the wood inside can be smoothly pulled out after the cement is dry.

As for the bark inside, it is very easy to clean. Just find a thinner piece of wood, sprinkle sand and gravel inside, and scrape it off little by little. They can even ignore the bark and directly apply a layer of cement on the outermost layer to ensure that the inside is smooth.

Liu Tan stood there looking at the drainpipe that everyone had made. Huo Guang smiled and asked, "Your Highness, can I use it?"

Liu Tan sighed: "It's more than okay, it's absolutely okay."

It seems that in the future, as long as it is not a scientific difficulty, he can just leave it to his subordinates. After all, his experience in some aspects is completely unable to support him in such a large project. The consequence of forcing himself is insomnia and hair loss.

There was really no other way. He didn't want to delay it too long and just wanted to build the city as soon as possible, so when he encountered difficulties, he forced himself to think of solutions all night long. How could he avoid losing his hair?

If this continues, he suspects that by the time he can return to Chang'an, he will really be bald.

Fortunately, before he became bald, the construction of the city was going smoothly. The city walls were not built entirely with cement, but were paved with stones, with cement used as a binder.

Originally, Liu Tan was worried that there would not be enough quicklime, but now he realized that quicklime might be enough, but for stones... he could only rob the nearby river valley.

After the city construction began, the tents began to be dismantled when the city walls reached a certain height.

When the tents are completely dismantled, it means that there will be basically no problem with the outer city wall. As for the inside... everyone can just use the tents to make do while building houses.

Huo Guang was obviously more anxious than Liu Tan, and he came up to him and said, "Your Highness, we can send troops now. We can also develop this place slowly later."

At that time, Liu Tan had already begun to consider whether to build a few public toilets and then connect the sewage facilities to the underground pipes.

However, this idea is a bit unrealistic, because water is necessary to connect the underground pipes, and the thing that the Western Region lacks most is water.

When Huo Guang said this, Liu Tan felt a little disappointed that the city was only a prototype, but he also felt that it would be bad to delay it any longer, so he said, "Everyone, have a good night's rest today. Tomorrow we will work out how to attack."

As Liu Tan finished speaking, Li Buyan suddenly rushed in and said, "Your Highness, Your Highness, something terrible has happened."

Liu Tan looked up at him: "What?"

Li Buyan was so angry that he almost lost his breath: "Little Kunmi led his men to attack Hu Hu and has now captured the Hu Hu King. He is looking for you to let you deal with the Hu Hu King."

Liu Tan: ??? Is this guy crazy?