Humans have long unearthed oil that is shallow or exposed to the surface due to crustal movements.

During the Northern Anniversary, the Turks attacked Jiuquan in Gansu Province, and the local soldiers and civilians ignited the "fire oil" and burned the enemy's siege tools, repelling the enemy and defending Jiuquan City.

In the rear beam, there was a case of putting "fire oil" in an iron tank and launching it to burn the enemy ship.

Shen Kuo of the Northern Song Dynasty mentioned in his Mengxi pen talk that near Yan'an, people used bamboo poles to drill wells for oil, and after burning, they could use soot to make ink to write, and the name "oil" has been retained to this day.

Zeng Gongliang's "General Essentials of the Martial Arts" in the Northern Song Dynasty has a very specific record of how to use oil as a raw material to make a powerful offensive weapon, "fierce fire oil".

Kang Yuzhi's "Yesterday's Dream Record" records that during the Northern Song Dynasty, the northwest frontier "all dug land to make large pools, vertical and horizontal, in order to store fierce fire oil", which was used to defend against the intrusion of foreign rulers.

Wei Yan is now located near the northwest border, and it is not surprising that he can find oil buried in shallow or exposed surface.

Zhang Yan got Wei Yan's order, and hurriedly ordered to go down, hundreds of torches were lit and thrown in the mountains and forests scattered with oil, the raging fire rose into the air, the cold north wind blew whistling, and the fire spread rapidly, sweeping the entire Qingyan Mountain.

After a while, the fire spread along the barren grass all over the mountains and fields to the camp of the Huns, and the neighing of thousands of horses and the terrible shouts resounded through the valley: "Fire, mountain fires, all over the mountains, run for your life!" ”

Li Jian and the other leaders heard the shouts and hurriedly rushed out of the camp.

The fires that spread all over the mountains rose into the sky, and Qingyan Mountain turned into daylight for a while.

The Huns were all confused, how did this fire start and how it spread so quickly.

The fire that permeated the soles of their feet made them have no time to think about it, they all rushed to the plank road between the valleys, rushed to the plank road, and then rushed out of the valley, but there were 140,000 Huns lurking on both sides of the valley, all rushing to the plank road, and the narrow plank road was so accommodating, the Huns had to wave their sabers, kill each other, and compete to run to the plank road.

All of a sudden, people turned on their backs, and the Huns were in chaos.

Although these Huns have lived near the border of the Han Dynasty for more than 200 years, they have stubbornly refused to be sinicized, and their minds are ignorant, and many Huns see the unavoidable mountain fires all over the mountains, and they no longer scatter and run, but kneel in the fire, and bow down in awe: "Great Kunlun God, you sent down the heavenly fire to punish us Huns, please forgive us Huns for their sins!" ”

The non-existent Kunlun God can't forgive them, and the raging mountain fire that poured oil on them won't forgive them, and those Huns who worship God temporarily when they are discouraged, once they kneel on the ground, their bodies are stained with oil, and they touch Mars slightly, the leather robe that was put on early because of the October day in the north instantly caught fire, burning all the fur on the whole body, and it was impossible to extinguish it at all.

A good and decent Hun man was incinerated by himself for no reason because of his incorrect beliefs.

In a short time, a living person turned to charcoal in a series of terrible screams.

Wei Yan held the clairvoyant mirror, looked at the Huns who set fire to themselves, and couldn't help but sigh, ignorance kills people.

Li Jian, the head of the Hun tribe, rushed out of the Hun camp and saw that all the trees on the slopes on both sides of the valley that had originally covered the sky were crackling and burning, and the fire spread extremely fast, almost in the blink of an eye, all the plants and trees around the valley that could be burned were burned, and the fire was raging and rising into the air.

Li Jian felt very strange, although the trees in the mountains are all pines rich in oil, although this season, the grass and trees are withered and yellow, and the weather is dry, but the fire should not spread so quickly.

His nose was sensitive, and he had a fight with the hounds raised by the Huns, and immediately smelled a pungent smell in the air, which he seemed to have smelled somewhere, and he sniffed it again, and finally determined what the pungent smell that permeated the jungle grass and trees was emanating from something: "Stone paint, it's stone paint!" It's not a heavenly fire! It's not a heavenly fire! Someone deliberately set the fire! It must be Wei Yan, only Wei Yan, a killing god, can use such a means! This stone paint is too easy to ignite, you can't get on your body, hurry up and take off your robe, hurry up and take off your robe, and hurry up and run to the place where there is no fire! ”

Under Li Jian's terrible shout, his tribal soldiers first came to their senses, regardless of whether the robes on their bodies were on fire or not, they all took off their leather robes and ran towards the plank road where the fire had not yet spread.

The Hun soldiers of Li Jian's tribe were running while shouting and repeating Li Jian's words just now.

The other Huns heard this, and they all hurriedly took off their flammable leather robes in panic, and ran to the plank road with their scimitars and bows and arrows, regardless of their good partners in war, horses.

Most of them realized that escaping the sea of fire did not escape the forbidden area of death, and there must be Wei Yan's brigade waiting for them outside the valley.

Wei Yan heard the stone paint in the mournful shouts in the valley, so he asked Jia Xu beside him in surprise: "What is the stone paint?!" ”

Jia Xu nodded: "Lord, stone paint is what you call oil, there is this kind of oil in Gaonu County, Shangjun, which can float on the river and burn, and is called stone paint by the locals, and the Huns also call it stone paint with the Shangjun people." ”

The brown-black flammable viscous liquid that Wei Yanfei poured on Qingyan Mountain was completely different from the gasoline and kerosene that had been refined in later generations, but crude oil that had not been refined.

Petroleum was first seen in Shen Kuo's "Mengxi Writings", and before that, it was called stone paint, water fertilizer, fat and water.

Petroleum has been discovered in the Western Han Dynasty, according to the famous historian Ban Gu of the Eastern Han Dynasty "Hanshu Geographical Chronicles" record, "Shangjun Gaonu County (Yan'an area), there is Weishui, fertilizer can be burned", that is, oil floats on the water of the Yan River, can be used as fuel, this is the earliest record of oil. Later, Jin Zhanghua pointed out in the "Naturalist Chronicles": "Water and fertilizer are also there, and it is not only the water of Gaonu County." Li Daoyuan of the Northern Wei Dynasty also quoted the "Naturalist Chronicles" in the third volume of the "Notes on the Water Classic" that the oil "is taken in a vessel, first yellow and then black, like a condensation, but (burning) is extremely bright, no different from the ointment." The plastering car and the water are very good, and the party people call it stone paint".

The plank road built during the Qin Shi Huang period should have been flooded by the wild grass long ago, but because the Han people and the Huns often pass through here, trampling for hundreds of years, there is no wild grass on the plank road, only sand and gravel, and the sand and gravel block the raging fire, looking from afar, this valley has all become a sea of fire, and the narrow plank road is like a black line, dividing the sea of fire into two sides.

Those Huns who were originally trapped in the sea of fire and could not be redeemed had to accept their fate and pray for the atonement of the so-called Kunlun God, after being reminded by Li Jian, they all began to throw the Kunlun God out of their minds, and ran to the plank road, ran to the plank road, and then ran along the plank road to the valley mouth on both sides.

But the plank road is only a few zhang wide, and it is only more than three miles between the valleys, and it can only accommodate 40,000 or 50,000 people standing at the same time, and there are more than 100,000 people who can escape from the fire.

In order to snatch the living space, the sabers they were originally going to swing at the Wei army slashed at their own people first.

The more chaotic they were to kill each other, the more it would not help them to seize the plank road and escape quickly.

If someone organizes them to evacuate quickly on both sides, they have at least a ninety percent chance of survival, but they kill each other, waste their time swinging their knives and slashing each other, forgetting that as long as people run on both sides, there will be a constant gap for them.

Wei Yan looked at these cannibalistic Huns with pity and sighed: "Hu people are Hu people, they don't know how to cooperate with each other to achieve a win-win situation, they can only kill each other in a zero-sum game." ”

Before he finished sighing, he looked uncomfortable, because he thought that the Han people were no better, and the entire history of the Three Kingdoms was a history of cannibalism.

Or that Hu-Han mixed-race Li Jian, he woke up to the fact that cannibalism was useless, or diverted and fled, in order to give those Huns who were trapped in the sea of fire and trying to squeeze onto the plank road a chance to survive, with him shouting, the other Hun leaders also restrained their men, divided into two directions, and fled to the valley mouth on both sides, the Huns who were originally standing on the plank road ran to both sides, leaving a gap in the middle, and those Huns who took off their leather robes and struggled naked in the sea of fire jumped on the plank road.

Wei Yan saw that the Huns had woken up from the cannibalism and rushed towards the valley mouth on both sides, so he ordered the crossbow soldiers at the valley mouth on both sides to get ready.

The Hun soldiers who escaped from the sea of fire along the plank road rushed to the valley mouth, only to find that there was already a wide and deep trench waiting for them at the valley mouth, and on the other side of the ditch there were Wei crossbowmen who were waiting for them with strong bows and hard crossbows.

Without thinking, these Hun soldiers picked up their bows and arrows and fired vigorously at the Wei crossbowmen on the opposite side of the trench.

However, the bow of the Huns has not been improved in the past three hundred years, and it is not even as good as the strong bow of the Maudun period, and the range is far less than that of the Wei army, and even less than the range of the Wei army's crossbows, and they can only deploy their forces in the narrow valley pass, while the Wei army can calmly deploy troops on the other side of the trench.

Five hundred Hun soldiers poured out of the valley mouth, and on the side of the ditch, four thousand Wei crossbowmen shot powerful arrows, arrows flew like rain, and the five hundred Hun soldiers died tragically under the strong bows and crossbows of the Wei army.

The bows and arrows of the Hun soldiers crossed the trench and fell to the ground, and they could not touch the bodies of the Wei army's crossbowmen at all.

Those Hun soldiers who fled from the fire panicked, where did they have any spirit to shoot bows and arrows that could hurt people, they were already great at being able to shoot arrows with bows, this was a one-sided battle.

The mouth of the valley on both sides was shot by the Wei army's strong bow and crossbow to kill thousands of Hun soldiers, the Huns in the back retreated, wanting to escape from the Wei army's bow and crossbow range, but there were many Huns who fled from the sea of fire and ran to the valley mouth, did not want to retreat to the sea of fire again, and could not retreat from the people in front, and even pushed the people in front of them, running forward, if the Huns in front were still afraid of the strong bows and crossbows of the Wei army, the Huns in the back raised their sabers to the retreating Huns under the order of the head.

For the Hun soldiers in front, running forward is to die under the strong bow and crossbow of the Wei army, and retreating back and being hacked to death by their own people, what to do, how to choose how to die, is a very heavy problem for them.

At this moment, there was a gentle and lingering song from the Wei army on the other side of the trench, which was thousands of Xiongnu women singing Xiongnu love songs calling for the return of Ailang, and Hun instruments such as Hu Ji played poignant Xiongnu mourning music.

The ordinary Hun men trapped in the valley suddenly came to their senses, they followed the head man to this valley to ambush Wei Yan and the Wei army, but their wives and children are still in the tribe, and the elite of the tribe are all transferred here, the tribe is very empty, when they hear these familiar music, they must have their wives and children and the cattle and sheep at home were captured by the Wei army.

All of a sudden, the Huns' morale, which had been burned by this fire, suddenly dropped to zero.

Except for those Xiongnu nobles, ordinary Xiongnu men felt that their whole body strength was gone, and they had no intention of being enemies with the Wei army, which controlled their wives and children.

Wei Yan ordered the scribes in the trenches on both sides to loudly announce their policy of sinicizing the Xiongnu to the Huns.

The policy of dividing the Huns into four ranks is a great benefit to those ordinary Huns, they can not only live the rich life of the Han people, they can enjoy the white rice and white noodles, silk and satin that are difficult to enjoy in their daily lives, but also can bid farewell to the extremely hard nomadic life of chasing water and grass and living in the wind and sun, and more importantly, they are all free, they have become free people like the Han people, and they are no longer slaves of those leading nobles!

If they perform well, they can not only be free herdsmen and homesteaders, but also participate in the Wei army's foreign Xiongnu corps, in this newly formed corps, there is no particular background, even if it is only a generation of slaves, they can also be centurion and thousand-commander by their own ability.

Wei Yan and Jia Xu looked at each other and smiled: "Embattled, live and learn!" ”

Wei Yan's policy of sinicizing the Xiongnu was tantamount to digging graves for those Xiongnu leaders and aristocrats, and they naturally refused to obey, and ordered the Hun soldiers below to dig soil and fill the ditch, so they had to rush through the trench and fight to the death with Wei Yan's Wei army.

The current Hun soldiers are different from the Hun soldiers of two or three hundred years ago.

At that time, the Huns were a submissive slave in front of the headman, and the headman asked him to offer his wife to the headman for play, and they did not hesitate.

The current Hun soldiers live on the border of the Han Dynasty, communicate and trade with the Han people more, and they have learned the Han people's bones of "those who know the times are Junjie", and they all think that their wives and children and the family's mobile property, cattle, horses and sheep are under the control of the Wei army, and the fire in the valley is still burning, it seems that this Qingyan Mountain must be burned to ashes to finish, and the only valley mouth on both sides that can escape is firmly sealed by the Wei Yan army, and the strong bow and hard crossbow of the Wei army are definitely stronger than Li Ling's bow and crossbow back then, and the source is endless, The Hun soldiers with a little head can see that the Huns have no way to live unless they submit to Wei Yan, and there is only one way to die with these head nobles, and those head people and nobles have been riding on their heads in the past to make a fortune, and now let Lao Tzu be buried with them in this sea of fire, no way.