"This is the bookstore I just mentioned, responsible for printing books and sorting out all kinds of manuscripts, and there is a library inside, where you can read books or borrow them to read slowly, and you can read them yourself when you have time. There is a big pool next to the fire station, which is the fire department, there is nothing to see ......, here is the hospital, if you feel uncomfortable there, you can go here to see a doctor, the doctor is free, but the medicine has to pay for it! The next place with a lot of toddlers is the kindergarten ....... ”

Wang You wrote down a new term in his heart, and unconsciously followed Zhen Qian back to the service center building, "Some of the places I showed you just now are the lowest level areas, as long as everyone in the valley can enter freely, such places occupy seventy or eighty percent of the valley, and the remaining places do not have the corresponding authority to prohibit entry, once it is found that the light ones are detained to check whether they have malicious intentions, and the heavy ones are killed on the spot, so don't have any luck ......mentality."

Zhen Qian had already reminded himself for the third time that his attitude had become extremely serious, and Wang You couldn't help but start looking forward to seeing those mysterious secrets.

"Where does this lead there?"

Wang You walked into the first floor of the service center, this time Zhen Qian did not take Wang You upstairs, but kept walking in the direction of the mountain he was facing. Yesterday, I saw a heavy carriage coming out of it, which increased Wang You's curiosity, could it be that this mountain is empty?

In the depths of the first floor of the service center, a group of guards in armor and weapons stood when they saw the two men approaching, and at the same time raised their right arms neatly, and shouted: "Salute! ”

Zhen Qian nodded at the guards, "I'm going to go in now, help me register, this is Wang You, who has just entered the valley, and he doesn't have the right to go in yet, I'm going to take him on a tour!" ”

"It's the valley master!"

The guards carefully recorded the time and personnel of entry on a piece of paper, and checked the identity cards of the two before letting them enter.

Walking along the tunnel with obvious artificial excavation, Wang You saw more than a dozen carriages passing by him, most of these carriages disappeared at the bend, and the whole tunnel did not know how many entrances and exits, and where did it lead?

After walking for about ten minutes, I don't know how many steps I climbed and how many turns I made, Wang You concluded that he was now in the middle of the mountains.

Suddenly, Wang You heard the sound of gurgling water in front of him, and then a light appeared in a corner, and a hole appeared in front of him.

"Is there a secret here?"

Wang You walked to the entrance of the cave, and there were several iron locks fixed on both sides of the hole, and the iron locks were paved with wooden boards, and the iron locks were connected to the cliff on the opposite side, and there was also a hole. Looking down again, a large frozen river appeared at his feet, "Where is this?" ”

"This is the Hutuo River!"

Hutuo River, also known as Grape River, originates in the area of Gushan Village, Taixi Mountain, Fanzhi County, Shanxi Province, flows eastward to Zangqiao, Xian County, Hebei Province, and flows into the Bohai Sea at the confluence of Fuyang River, another tributary of Ziya River.

The Hutuo River has a great difference between east and west, when passing through the Taihang Mountains, there are a lot of waterfalls formed, there will be no boats on the river that can not be rowed, and there will be no boats coming and going, until the development of water conservancy construction in later generations, a lot of water conservancy hubs have been built one after another, the north embankment and the south embankment have been built, this river is often flooded in the Tang Dynasty, and it is also a place where soldiers must fight.

Wang You was not surprised, why is there not much of a big river in Hengzhou, just think about it, "It turns out that the valley is hidden by the Hutuo River?" ”

Sendai Village is not far from the Hutuo River, but it is outside the mountain, the terrain is relatively flat, and the current is not fast, and this place is obviously far from the mountain pass, and you can see that it is surrounded by mountains, and I don't know how far it is from Sendai Village.

The two walked across the iron bridge, and suddenly Zhen Qian asked, "Wang You, have you ever thought about how you make a fire and cook in the valley?" ”

"Firewood, of course...... Wrong! ”

Wang You said half a sentence and felt that it should not be very simple, in the morning, I didn't see the green smoke coming out of the chimneys of every house, not to mention that the wind in the valley was very small, if thousands of people made a fire to cook at the same time, wouldn't the valley be made of black smoke miasma, coupled with the faint smell of soot that he smelled in the valley, he suddenly thought of the charcoal he saw in Sendai Village (the name of ancient coal): "It's charcoal!" ”

"Here's coal?"

"That's right! There's coal here, and the carriage you see in the tunnel is the one that pulls the charcoal! ”

The ancients discovered coal very early, and also knew that coal can be burned, and the area of Jingcheng is rich in coal, but the use of coal has not been taken seriously, one of the reasons is because there is sulfur in the coal, and a large amount of gas is produced after combustion, which is toxic. It was not until after the Song Dynasty that desulfurization technology appeared, and coal was used in smelting, and the steel output of the Song Dynasty developed by leaps and bounds.

"Isn't charcoal poisonous?"

Due to the ignorance of the ancients about the charcoal, there are many misunderstandings in the understanding, some people use the charcoal for heating, but they get up early in the morning to find that the family is all dead, and the smell of the charcoal is unpleasant, so they regard the charcoal as a bad thing and abandon it.

Later generations knew that the culprit was caused by ventilation and carbon monoxide, but the ancients did not know it and superstitiously believed that charcoal was not good.

"Do you feel warm in your room?"

Seeing Wang You nodding, Zhen Qian said again: "The whole valley is using charcoal, the key is how we use charcoal, the crude use of the previous way is indeed easy to cause harm, but these problems have been solved in the valley, there are precautions for the use of charcoal in your booklet, as long as you follow the correct steps to use it, you can eliminate the harm caused by charcoal!" ”

There are many reasons for this, Zhen Qian doesn't want to tell Wang You for the time being, if thousands of people in the valley make firewood for dinner, they don't know how many trees to cut down every day, and the surrounding trees naturally can't be cut, and it's inconvenient to go farther, and there is also the problem of utilization, but the most important thing is the problem of smelting, the area around Jingcheng is rich in charcoal, and if Zhen Qian is not good at using it, he is a fool.

The two walked to a hillside, stood on the hillside and looked down the mountain, the mountain was crowded, a cart of charcoal dug out of the deep pit poured into the carriage and galloped away, the whole scene was very spectacular, from the mountain it looked like countless ants carrying things under the mountain, Wang You was dumbfounded.

"Is there a lot of coal here?"

"I don't know ......", Zhen Qian really doesn't know, who has nothing to remember the reserves here, but the coal seam here is very shallow, and it took nearly ten years of mechanical mining in later generations to exhaust it, how can the Tang Dynasty say that it should not be a big problem to use one or two hundred years!

"But some people estimate that it is still possible to dig here for hundreds of years!"

(End of chapter)