When Li Shimin asked about the serious matters, Li Mu also cheered up and led Li Shimin to the anvil to show the heating coal stove he had made in the past few days. This heating coal stove was not from the system. After all, the system he brought was a game system. The characters in the game did not need to be heated, so naturally there was no heating coal stove. This heating coal stove was created by Li Mu based on his memories of his previous life. When he was a child, there was no heating in the orphanage, and the heating coal stove used in winter.

When it snows, the children will gather in the same room. Because the orphanage has limited funds, it is impossible to buy much coal. At this time, the old dean will live with the children because he is worried that if he doesn't watch, the children will have problems filling the coal by themselves. The cost of coal is quantitative every day, and it is better to weigh it with a table. How many kilograms per day cannot be exceeded. If it exceeds it, the orphanage will have no coal when the snow has not melted in the spring next year.

And more importantly, he was worried that his child would get gas poisoned if he filled the coal by himself.

But in fact, the probability of a heating coal stove being dangerous is very low. Basically, an adult, if he pays a little attention, he will not have any problems. In the later 1980s and 1990s, when buildings were not yet popular, heating coal stoves were a must-have for northern families.

This thing is very simple to make. It doesn’t use too good steel, but the second best cast iron can be used. With the current iron smelting technology of the Tang Dynasty, it is no difficulty to make it. As early as the Qin and Han Dynasties, when making bronze ware, the people of the Central Plains had already mastered the process of mold making bronze ware and made heating coal stoves. This technology was just right, but it was just to replace bronze with iron, which was very simple.

Li Mu found several bronze craftsmen in the Ministry of Works, drew drawings for them, and asked them to burn molds. The stove he showed to Li Shimin now was poured with this mold.

He made the furnace barrels on the stove themselves, connected them together, and then sealed the gaps with mud. A standard 1980s heating coal stove was completed.

Li Mu was very satisfied with his craftsmanship. He was very confident that this cast iron coal stove was much better than the stove he used to heat rice when he was in elementary school. But obviously, Li Shimin didn't know how to appreciate it. He watched it next to him for a long time, but he really couldn't understand it. He pointed to the coal stove and asked, "What is this for?"

"Does Your Majesty know about coal stone?"

Li Shimin nodded and said, "Of course, I know that although coal stones can be burned, they must be ventilated, otherwise poisonous smoke will be emitted. Therefore, they cannot be used to keep warm, they can only be used to make iron... What are you talking about this?"

"Your Majesty, with this thing, you can solve the problem of poisonous smoke." Li Mu said seriously: "Winter is approaching, and it will almost snow in another month. I asked the doctor of the Yu tribe, and he told me that the coal stones are everywhere. If this is true, wouldn't it mean that my Tang Dynasty has endless fuel? If the people have this furnace, will they still freeze to death in winter?"

When Li Shimin heard Li Mu's words, the first thought that came to his mind was "A Chinese Odds". Since ancient times, who has not known that coal stones are poisonous. If they were not really poor, unable to afford charcoal, and unable to get dry firewood, who would risk their lives to use this thing to keep warm? Everyone knows that coal stones can be combustible, but few people have used them since the Qin and Han Dynasties. Doesn't this tell the problem?

Now Li Mu has created a strange-shaped "stove" and said that he has solved this problem. How could Li Shimin believe it?

Li Mu saw it and before Li Shimin could speak, he took the initiative to say: "If Your Majesty doesn't believe it, I will demonstrate it for you now."

As he said that, without waiting for Li Shimin to agree, Li Mu called Li Chongyi to bring coal over. When Li Chongyi heard Li Mu's instructions, he went to Curry to bring a large basket of coal, weighing hundreds of pounds, but in his hands, it seemed as easy as carrying a chicken.

The basket was put down heavily, and Li Mu threw the coals into pieces one by one. Then he used dry branches to draw fire from the under furnace. The coals left by the Ministry of Works were all good coals, and they caught fire when they encountered fire. The fire soon became prosperous. What followed was the choking coal smoke. Although Li Shimin did not escape, he raised his hand and covered his mouth and nose with his sleeves, and said, "Li Mu, look at the smoke, this is coal poison. Do you want to poison me?"

"Your Majesty wait!" Li Mu cursed in his heart, why is it so unlucky? He caught up with the windy weather. He quickly brought the bamboo fan over and asked Li Chongyi to fan the wind.

Anyone who has grown the stove knows that even in the windy weather, as long as the steadily burns and turns red and the heat rises, it can carry the storm smoothly, and it will only take a while for smoke. But today there is a little more coal filling today. After about one stick of incense, the coal turns red and the smoke stops.

Li Shimin kept holding on to it and didn't leave. It was not that he was not afraid of life and death, but that Li Mu did not leave. He wanted to see what Li Mu was going to do. He saw the changes in the fire with his own eyes and felt the most sincere. He did not expect that Li Mu's stove would really become. Although it was choking at the beginning, he also knew that it was related to the direction of the wind. Even if it was not the stove, there were also winds when marching and burying the pot to make rice, which was not a problem.

When the smoke dissipated, Li Shimin lowered his hand, which was covering his mouth and nose, and leaned closer to smell it, and no longer smelled the pungent smell. He imitated Li Mu, took the stove hook in his hand and lifted the lid. Seeing that the smoke produced in the stove was out along the iron tube above the stove, he couldn't help but be surprised and said, "My dear, can you actually control the cigarette?"

Li Mu complained in his heart, Boss, you are indeed realistic enough. You usually call me a name, and you are angry. Now that I see something, my dear will come. The treatment is really obvious.

Li Mu quickly squeezed out a gratitude expression and said, "Your Majesty, it's not that I can control the cigarette, but that I discovered the reason for the rising smoke, so I made a furnace and drove the cigarette out. Now that your Majesty has seen it with his own eyes, do you think my invention is usable?"

Li Shimin pondered for a moment, shook his head and said, "This stove is available, but it is not practical for the people. Li Mu, have you ever thought about how much this stove is? I, the Tang Dynasty, lack of iron, and your stove will probably cost hundreds of kilograms of iron, which is not a problem for the Duke, Marquis and nobles, but for the people, they cannot afford it at all."

Li Mu had thought of it for a long time and said, "Your Majesty has seen through the disadvantages of this heating coal stove at a glance. That's right, the cost is the biggest obstacle to the implementation of this heating coal stove. I thought for a long time and finally thought of the second method."

After Li Mu finished speaking, he took Li Shimin to the next door, which was the room where he was usually busy and napping in the studio. A firewall had been built in this room, which he asked Yuwengui to send someone to repair a few days ago.

"Please look at your Majesty. This is another way I thought of. Your Majesty just saw that the reason why the heating coal stove can avoid poisoning is to export smoke. The most important thing in using coal stone is to export smoke." Li Mu walked to the wall, reached out to touch the wall, and said, "This wall is a double wall, hollow. I burn coal here, and the smoke can pass through the hollow wall and then export it. I asked the craftsmen to burn tiles like the iron tube you saw just now, connecting these tiles together and sealing them with mud can also have the same effect. It does not require iron, but can also keep warm."

Li Shimin walked closer and saw Li Mu's demonstration just now. Looking at the firewall, it is almost understandable, but it is not easy to deal with major issues in people's livelihood. Li Shimin still let Li Mu demonstrate in front of him.

Li Mu had to ask Li Chongyi to take the coals and put them in a brick stove, and then ignite them. As Li Mu said, the smoke was exported and the entire wall was hot.

Li Shimin finally showed a satisfied expression and laughed: "I am really talented. This fire wall is not difficult to build. The people can build it themselves, and coal stones are everywhere. It seems that the people of my Tang Dynasty will not have to be frozen in the future, hahaha..."

"And." Li Mu interrupted Li Shimin's laughter, almost choking his saliva. Li Shimin glared at him unhappily and said, "What else?"

"Your Majesty, please sit down." Li Mu signaled for a moment. Only then did Li Shimin notice that there was a staircase above them that was about knees. He sat on it like Li Mu, feeling the heat under his butt, and couldn't help asking, "What is this?"

"Your Majesty, this is a bunch of kangs, and it is also my invention."

"Pank kang?" Li Shimin frowned and said, "I have only heard that there is a kang in the north, but what is a kang? Is it different?"

The kang was not an invention of the Goguryeo nation. It had already been the prototype of the kang in the Western Han Dynasty of my country. However, the kang was very simple at that time. It was dug a hole under the cover, heated the stone slabs, and then lie down to sleep when the stone slabs were about to cool down. It was not very practical. Later, it was gradually abandoned. If it were about the "kang" in the world, it was still the best technique of the Goguryeo people.

"New Book of Tang Dynasty: Biography of Goguryeo" records: "Everyone is used in winter, and warm fire is burned underneath." The kang in Mayi, Li Mu's hometown, was also a technique passed down by Goguryeo craftsmen who were plundering when Emperor Yang of Sui conquers Goguryeo. The general structure is similar to that of later generations, but the smoke is flat, which means that it burns here and there, and the smoke stays in the kang for a short time and is cool quickly.

The tray kang created by Li Mu was a flower-pan kang built in the era in which he lived in later generations. He had already summarized the experience of his predecessors. He wanted to make a hollow tray kang in one step, but he had no cement and could not make a kang board with high strength and large area. He could only use bricks to build a flower-pan kang. A flue was built in the middle of the flower-pan kang. The smoke came out of the stove and had to be coiled in the flower-pan kang for more than ten weeks before it could spread out smoothly. Because the built flue tray was coiled and the smoke was also coiled, it was called a tray kang.

The kang in Goguryeo in this era took at least eight hundred years to evolve to the level of a flower-pan kang. Li Mu took out the kang at this time, which was definitely an invention of several eras in advance.
Chapter completed!