Xu Shu glanced at the arc on the map in Cao Cao's hand and explained, "That's called a contour line!" The number next to the contour line represents the elevation of the lot represented by this circle! ”

"What do you mean by altitude?"

Xu Shu's eyes did not leave Li Dao's army, and he said impatiently: "I can't understand for a while!" Roughly speaking, it means how high the mountain is on the surface! ”

"Oh!" Cao Cao Cancan nodded. It was the first time he had heard of how high the mountain could be on a map. "This Pastor Jiao Ji is such a genius, I have never heard that a map can be drawn like this!"

"This is all Yi Ge'er's idea! Later, he taught it to other pastors. Mapping this kind of topographic is now a compulsory course at church colleges, and almost every graduate does it. In addition, it is not only Pastor Jiao Ji who has drawn such a map in Shantun, every church has such a task! Xu Shu glanced at Cao Cao and said, "That is to say, whenever there is a church of Our Lady in a place, the main church of Our Lady will clearly grasp every grass and tree in that place." Where there is a village, where there is a big road, where there is a small road, where there is a forest, where there is a field, and even where there is a rock suitable for making glass, there is copper ore, it is clear. ”

"Huh?" Cao Cao was shocked, "What is Ziqi doing to inquire about this?" ”

Xu Shu glanced at Cao Cao and asked rhetorically, "Brother Meng De, what do you say?" ”

Cao Cao swallowed violently, "Undoubtedly, for war!" ”

Xu Shu smiled, "At first, I thought that Yi Ge'er was applied to strategy. After talking, I realized that it was not the case at all. The reason why Yi Ge'er explored these was to know which trade route was easier to walk, where the inhabitants were more affluent, and where there were what kind of local products were worth operating. Where else can we get cheaper raw materials...... It's for profit! I never thought that now the application will complement each other more in war! ”

After listening to Xu Shu's explanation, Cao Cao laughed, "This is in line with the truth in Ziqi's "Yuan Fu", 'Everyone is self-interested.' However, when it is self-interested, it is guided by the way of the Circulating Heavenly Dao. Promote the development of the world when it is self-interested. ’”

"What Brother Meng De said is very true!"

Cao Cao carefully returned the topographic map to Xu Shu and asked, "Is it time?" ”

Xu Shu glanced at Li Daojun at the bottom of the mountain again, and ordered: "Thunder drum, fire the cannon!" ”

Boom...... Boom...... Boom...... The passionate drum beat sounded from the side of the valley demon mother Niangniang Mountain, reverberating the echo of ancient times, all the way to the east mountain.

The top of the east mountain immediately raised the melody of war drums, "Knock knock...... Smack......"

With the sound of a cannon, countless church guards appeared on the cliffs on both sides. They rolled out hundreds of rattan balls that had been braided in advance and set them on fire with torches. "Putting ......"

The order sounded, and the blazing rattan balls tumbled down the hillside all the way, like the scorching sun falling from the sky, igniting all the dry grass and trees in the early spring rainy season, raising the scorched smoke all over the mountain. In the end, he broke into the narrow Xiliang array.

The heavy vine balls accumulated all the way of the gravitational potential energy that burst out in an instant, and the strong inertia prompted hundreds of rattan balls to cut Li Dao's army into several sections like countless stones passing through. Countless soldiers were crushed into meat sauce by rattan balls, thousands of soldiers were drowned in the fire, and there were terrible screams everywhere.

This is not the end of the fire attack, on the contrary, it is only the beginning.

At the same time as the rattan ball hit the ground, tens of thousands of fire arrows fell from the sky and fell into the canyon. After a round of arrows, the crossbowmen all over the mountain drew their arrows again, lit them from the torches in front of them, and set up the bowstrings. With a uniform order, "put" while loosening the strings.

The overwhelming rocket took off again, and dark clouds obscured the blue sky in the valley.

"Ah......h

Li Dao was shocked, and the big knife dance was impenetrable, and he struggled to block the flying feathers in the sky.

But the arrows are so dense that they can't protect their horses.

The mount under the crotch was hit with several arrows, and the law screamed and fell to the ground. Li Wei rolled for several weeks before removing the force of the impact so that he would not fall and be injured. Just as he was about to get up, he saw another cluster of flying locusts flying.

Seeing that he couldn't hide, he saw the deputy general Ji Wu facing away from him in a hurry. hurriedly rushed forward and grabbed Ji Wu in front of him.

"Puff puff ......"

"You?" Ji Wu couldn't imagine that Li Wei would use himself as a shield, spit out a few mouthfuls of blood, and died of staring.

Li Wei, who had survived the catastrophe, let out a sigh of relief, gently closed Ji Wu's eyes and muttered, "Brother, I'm sorry!" When you return to Hangu Pass, General Ben will settle your family in a good life. From this time on, thy father is my father, thy mother is my mother, thy son is my son, thy wife ...... My wife! Let's go in peace! ”

He threw Ji Wu's body aside, raised his broadsword and shouted to his corporaries, "Sons, we are in a desperate situation, and we can only escape from Ascension by fighting to the death." Formation, Formation Formation, Formation Formation, Forge Forward! ”

A group of Xiliang soldiers also knew that they were trapped in a dead end, and under the strong drive of survival, they became orderly, covering each other, dodging fire arrows, and in the next rain of arrows, there were fewer and fewer dead and wounded.

However, at this time, Li Dao suddenly heard a strange movement around him. Following the prestige, it came out of the rattan ball that stopped in the middle of the road.

He subconsciously leaned over to check outside the flames of the rattan balls, and saw that there were many pottery altars piled up in the vine balls. Some of the pots have cracked, oozing a crystal liquid. Wrinkled his nose and sniffed carefully, and there was a strong aroma of wine under the cover of the burning smell. "It's ...... Wine? ”

Li Wei suddenly remembered that he had heard that Luan Yi used immortal brewing to make a very strong combustion fuel. His eyes suddenly widened, and he ran back with his head in his hands, "Pay attention, stay away from the rattan ball, run!" ”

After all, it was half a beat late. Li Dao had just run a few steps when he heard the roar of an explosion behind him.

Dozens of jars of immortal brew ignited the air at the same time, immediately causing a powerful explosion.

The roar of explosions rang out everywhere in the valley, and the echoes rippled as if the sky was falling apart.

The huge shock wave knocked countless Xiliang soldiers to the ground, and the soldiers who were close to the source of the huge explosion died tragically, and the fragile ** was dismembered, and their arms and legs flew everywhere. Once again, the valley was engulfed in flames.

True, the explosive power of alcohol is far inferior to gunpowder. But for the second century A.D., when there was no word for "explosion", the spiritual shock it brought can be described as shocking.

The confidence that the Xiliang soldiers had just built up completely collapsed after seeing the robe turn into strips of meat with a roar.

Tens of thousands of Xiliang soldiers cried and shouted and hugged their heads and ran away.

Li Dao himself was even more miserable, and at the moment of the explosion, he was collapsed more than ten steps away and hit his head on the mountain. The helmet and skull shattered together, the eyeballs burst out, and the nerves swayed around the bridge of the nose.

Cao Cao, who was standing at the top of the mountain, looked at the sea of fire below the mountain in shock, and couldn't say a word for a long time. Before, he only knew that the fairy brew was delicious, but he never knew that the original fairy brew could form such a shocking effect. He touched his big belly and asked, "What's this......?" This...... Brother Yuan Zhixian, drinking the fairy brew won't blow up the belly, right? ”

Xu Shu smiled and waved his hand, "How can it!" The immortal brew we usually quote is only more than 40 degrees, and it is not harmful to the body. As for the immortal brews below, they are all 70-degree high liquor, which cannot be drunk, but can only be fueled. In addition, the Immortal Brew explosion also requires a lot of conditions, a closed space, and a burning fire source. It won't explode if you drink it in your stomach! ”

"Oh!" Cao Cao pursed his lips, "What is 'degree'?" ”

"Brother Yi calls it alcohol content!" Xu Shu originally wanted to explain, but after thinking about it, he didn't particularly understand, "This thing is not very clear, if Brother Meng De is interested, you can ask the brewing master of Fengge when you have time!" ”

Cao Cao Cancan nodded and said leisurely: "I sometimes wonder what Ziqi has in his stomach!" How do you even know this! ”

Xu Shu did not fully agree with Cao Cao's statement, he said: "In fact, it is not that Ziqi knows more, but that he tries more." Let's take this immortal brewing explosion as an example. In fact, Yi Ge'er didn't seem to know that the immortal brew could explode at first, but when he was twelve years old, he accidentally discovered that a high concentration of immortal brew could burn. Later, he began to try to make something interesting with the characteristics of the immortal brew burning, but he didn't expect it to happen. He called it an alcohol lamp, but the structure was very simple, it was a small glass bottle, filled with fairy brew, and then stuffed a cotton cloth into the bottle. The cotton cloth is stained with fairy brew, and when lit, it can be burned. It is said that the temperature of burning is many times higher than that of charcoal fires. Yi Ge'er was very satisfied with the alcohol lamp. But one day, an accident happened! ”

"But the alcohol lamp exploded?" Cao Cao immediately guessed the unexpected ending.

Xu Shu nodded, "That's right! After Yi Ge'er lit the alcohol lamp, the alcohol lamp suddenly exploded. The flames splashed all over him, instantly setting his clothes on fire and setting the house on fire...... Luckily, there was a water tank in the house. Yi Ge'er jumped into the tank, and our brothers put out the fire in time so that they would not be buried in the fire, but I know that now, there is still a burn mark on Yi Ge'er's left arm! ”

Xu Shu chuckled, and continued: "When he got wet and came out of the water tank, Brother Yi covered his left arm and grinned in pain, but with a thick smile on his face, he kept exclaiming: 'I see, so it is, the fairy brew can still explode, I should have thought of it. 'Can Brother Meng De imagine that?' At that time, Yi Ge'er was like a madman! ”

Cao Cao nodded, and in his memory he seemed to have seen Luan Yi's inexplicable madness. It seems to be that winter...... Yes, it's winter. That winter, a domestic servant in Luan's mansion died of carbon poisoning. Luan Yi treated his servants very well and was very sad, so he asked Cao Cao and Yuan Shao to drink stuffy.

When he was half-drunk, Luan Yi was very sad and always muttered strange language such as "how to prevent carbon monoxide poisoning". didn't talk to Cao Cao and them, patted his head and pondered for a long time, as if he suddenly found the answer, and laughed again. was in a good mood, and the wine was drunk freely, which made Yuan Shao and Cao Cao drunk.

The next day, strange iron passes were erected on the hut of the Luan family. Luan Yi said that it was called a chimney, and the chimney was connected to the charcoal stove in the house to dispel the carbon poison in the house. He also enthusiastically suggested that Yuan Shao and Cao Cao also build such a chimney at home.

However, Yuan Shao and Cao Cao always felt that it was not beautiful to have such a chimney on the house, so they did not do what he said.

Xu Shu glanced at Cao Cao who was contemplative, and said, "Therefore, Brother Yi'er knows so much, not because God has given him much talent. In fact, when he first studied at Yingchuan College, Yi Ge'er's schoolwork was only mediocre. The reason why he can achieve so much now and become the first divine talent among the eight talents of salvation is that he himself has a strong thirst for knowledge. Moreover, when exploring the unknown, Yi Geer rarely reads from the book, he pays more attention to his own practice, believing that only the conclusions that have been personally demonstrated are the real conclusions, rather than the words of the ancestors in the books. ”

"Hands-on? Practice? Cao Cao kept repeating what Xu Shu said.