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In the ordnance prison of Great Qin, there were first-class skilled craftsmen in the country, and at this time, most of them were listening attentively to the explanation of Emperor Great Qin.

Qin Mu not only explained, but also made a small experiment with his own hands.

I saw that he found two pieces of paper each one foot long, took one in one hand, and let the two pieces of paper hang down naturally, and the two pieces of paper were about two inches apart.

"If I blow down vertically through the gap between the two pieces of paper, guess what, will the two pieces of paper float outward?"

"Yes."

After Qin Mu asked, almost everyone thought that the two pieces of paper would definitely be blown to both sides by the air current.

Seeing that they answered so affirmatively, Qin Mu didn't say much, and directly blew a long breath vertically downward from between the two pieces of paper, so that all the skilled craftsmen in the ordnance supervision did not expect that the two pieces of paper did not float outward as they expected, but instead stuck inward together.

It wasn't until Qin Mu blew it all in one breath that the two pieces of paper separated again and hung down naturally.

"You try."

Qin Mu said and handed the piece of paper to the curious craftsman, and everyone followed Qin Mu's example just now, blowing vertically down from between the two pieces of paper, and strange things appeared again, the two pieces of paper still did not float outward, they were all pasted together.

Some craftsmen did not believe in evil, so they took a deep breath and made their abdomen bulge, so they blew down hard, but the harder they blow, the tighter the two pieces of paper were attached.

In the end, everyone was convinced.

Qin took back the piece of paper again, this time with only one sheet, not vertically, but horizontally, with his thumb clamped on top and his four fingers on the bottom, because the paper was soft, the place where the four fingers could not hold it was still naturally bent down.

Qin Mu said: "You pay attention, now I am sticking to the top of the piece of paper and blowing in the horizontal direction. See what happens to it. ”

As a result, when Qin Mu took a long breath hard, the part that was softly hanging down where his fingers couldn't hold it immediately floated horizontally.

At this moment, all the skilled craftsmen didn't think it was strange, but when Qin Mu asked them why this phenomenon occurred, no one could answer.

Qin Mu didn't expect them to understand, so he patiently explained: "Let me tell you this, there is pressure in the air, and when the air is still, the pressure on all sides will be very uniform. If the velocity of air passing through guò from both sides of the paper is the same, then the pressure on the paper on both sides is still uniform, and the paper will not stick together or float up;

But when we blow air, it is artificially causing the air to flow faster on one side of the paper. Note that this is an iron law: the faster the air passes through one side of the paper, the less pressure will be applied to that side;

If the pressure on the other side of the paper remains unchanged, the relative value will be greater than that of the blowing side, and the paper will be pressed to the side with less pressure. So you see the phenomenon of the paper floating horizontally.

Again, I emphasize that theoretically, the two sides of an object, which side of the air moves faster. The less air pressure this side is subjected to.

If it is a horizontally placed object, the lower the pressure above, the greater the pressure, or lift, exerted by the air below.

Take a closer look at the wings of birds. You will find that when the wings of all birds are spread, there is an arc upwards. Why not a flat, or downward arc? I tell you that this is the secret of the birds being able to fly in the sky. ”

So when people heard this, they all held their breath and flew, always thinking that it was the dream of human beings, and that thousands of households would pay the price of their lives in order to fly.

In the eyes of the craftsmen, it is normal for him to know the secret of the flight of birds, so everyone is extremely eager to know.

Qin Mu looked at a pair of eager eyes, and then said: "Because the wings of birds have an upward arc, when the air passes through the wings of birds, the flow speed above the wings will increase, the pressure above the wings will become smaller, and the air pressure under the wings will provide a rising pressure to the birds, just like the pieces of paper that floated up just now, this is the mystery of their ability to fly." ”

A young craftsman named Shi Qing couldn't help but ask, "Your Majesty, why do the wings of birds arc upwards and the air speeds up when it is above the wings?" ”

Qin Mu said encouragingly: "This question is very good, we can immediately make a model to test it." ”

Under Qin Mu's guidance, some of the craftsmen in the ordnance prison quickly dug out a wooden plank, with a small arc slightly inward below, and an upward arching arc similar to a bird's wings was planed out on the top.

Then he took a basin of water, and Qin Mu took the planed wooden board and paddled horizontally in the water;

After Shi Qing observed carefully, he quietly realized: "Your Majesty, the villain understands, air and water, like water, cannot tolerate gaps, and they can't wait to fill them as soon as there is a gap." Because the wings have an upward arc, due to the obstruction of the wings when flying, a gap will be created behind the upper part of the wings, so the air in the upper part will be in a hurry to fill this gap, which will cause the air in the upper part to flow faster;

According to what Majesty just said, which side of the air flows fast, which side of the pressure is small, birds use the arc of the wings to arch upward, so that the air in the upper part of the wings becomes faster, so the air in the lower part lifts the bird up. ”

"Yes, that's exactly right, I want you to make a glider of zuò, if you don't understand this principle, you can't fly, if you can figure out this principle, let it be like the wings of birds, and it won't be impossible to fly with people."

The reason why Qin Mu spent so much time explaining these things to the craftsmen was that he hoped that the craftsmen would not only make gliders based on his drawings, but also understand the principles;

If you understand this principle, you can draw inferences from one another and apply it to many things, not just to make a hang glider, for example, when a sailboat is sailing against the wind, you can use this principle to sail.

Qin Mu hoped that through his own efforts, the people of Daqin would learn more about some basic sciences faster, and with these basic sciences, they could talk about the great development of science and technology.

He took the freshly cut wood and continued to explain to them: "You see this arc that arches upward, and when it moves forward, this arc must bring resistance, but within a certain range, the greater the curvature of the upper arc, the greater the lift-to-drag ratio;

The radian exceeds a certain range. The resistance increases very quickly, and the lift-resistance ratio will decrease, so how is this arc the most appropriate, you can catch a swallow and accurately measure the swallow's wings to obtain an approximate radian value;

But the swallow's wings are very small, and the measurement is not accurate, and when they are enlarged, they are very different. So after you get the approximate radian value, you still need to try it repeatedly. in order to derive a maximum lift-to-drag ratio. ”

Shi Qing volunteered and said: "Your Majesty, can you hand over this project to the villain, the villain will definitely do his best to complete the task assigned by His Majesty." ”

Shi Qing was very young, only twenty-six years old, and from the burning eyes in his eyes, it was not difficult to see that he was extremely eager to be the first to fly into the sky.

Interest is the best teacher, and from what he said just now, Qin Mu felt that he had a high level of understanding. So he said, "Okay, I'll leave this research and development work to you, I hope you don't disappoint me." ”

"Long live, long live. Hooray! Shi Qing was so excited that he knelt down and kowtowed repeatedly.

Qin Mu told him some things about how to reduce the weight of the glider, how to use the angle of the dive to increase speed and gain lift if he could fly, and so on, and Shi Qing wrote them down one by one.

In addition to the glider, Qin Mu also went to see the development of the flintlock pistol. China has long had fire sickles, and fire sickles are made of flint, and flint is rich in phosphorus and manganese. It's easy to fly out of Mars when tapping.

Loading flint onto the gun instead of the traditional arquebus, this is a project that Qin Mu has been developing for a long time, and a few samples have been produced, and I believe that as long as they are improved together, they can be mass-produced.

In addition, Qin Mu also watched the first lathe manufactured by the Ordnance Superintendent.

The ancients were not very unfamiliar with lathes, and people knew about using simple lathes to process things like jade for a long time.

In ancient times, the process of jade manufacturing was extremely complex, grinding a piece of jade needed to draw samples, sawing materials, making embryos, making tin, light, carving and other processes, the jade material was very hard, ordinary metal knives could not be carved;

When processing, it is generally installed on a table and stool with a pedal belt transmission device to drive a stone to rotate, and the stone is large and small, and the drilling and elaboration are all completed in this way.

Although this tool for processing jade is relatively rudimentary, there is no doubt that it is the original form of the machine tool.

Now the Ministry of Industry has mined a kind of ore called heavy stone by craftsmen from the area of Dagengling, Anfu, southwest of Jiangxi, and obtained a kind of steel through high temperature and a series of complex smelting processes, which is extremely hard and can be used to make lathe drill bits to process iron.

Just the appearance of this kind of drill bit, Qin Mu had a new understanding of the smelting technology of this era, and what made him even more unbelievable was that the craftsmen in the ordnance prison actually said that there were similar drill bits used for iron tools in the Sui and Tang dynasties.

Qin Mu didn't know much about ore and didn't know what this heavy stone was.

He asked, Shang Xi, who improved the smelting furnace last time, once again improved the smelting method, he made a kind of pot with graphite clay, and then cut the iron into pieces, placed it in a closed graphite clay pot, heated outside the pot, and the iron melted into high-carbon molten steel, which was cast into small ingots and forged into the desired shape.

The steel used for the barrel is also a high-strength steel smelted by cutting the iron into pieces and putting it into a graphite clay pot.

In addition to adding heavy stone powder, the smelting process is more complex and the cost is higher, but seeing the efficiency of the lathe drill bit to cut iron, Qin Mu had to sigh, it seems that he has once again underestimated the wisdom of the ancients.

With lathes, drill bits, and ordnance supervision when processing gun barrels, not only the efficiency is increased by dozens of times, but also the specifications are one, which is conducive to mass production.

Qin Mu was full of relief, the Chinese did not lack wisdom, but they lacked a soil to display their talents before.

Now just give them a piece of soil, and they don't have to point fingers on their own, and they can bear amazing results.

Whether it was the various processing techniques of the Ordnance Supervisor or the smelting methods that Shang Xi had repeatedly improved, they were all explored by themselves, not forcibly instilled in them by Qin Mu.

As soon as Qin Mu picked up a barrel that had been rifled out with a lathe drill, he saw that Huang Lianshan hurriedly walked into the ordnance prison when he saw that he did not accept the command at night.

Huang Lianshan went to Qin Mu and said after giving a salute: "Your Majesty, there is news from Mobei. ”

Huang Lianshan stopped after saying this, Qin Mu said a few more words to the craftsmen, encouraging everyone to innovate more, and then walked out of the ordnance prison with a satisfied smile, as soon as he got into the car, the smile on his face was closed, and he asked Huang Lianshan: "What's wrong with Mobei?" ”

"Your Majesty, after the men and horses led by Chitait and Tuya entered Mobei, they united with Zasaktu Khan Norbu to attack the Tushetu tribe fiercely, two months ago, the Tushetu tribe was defeated, and the people and horses of the Ten Pavilions went to the Six Pavilions, and the Tushetu Khan led the remnants to retreat to the Buerhan Mountain"

Huang Lianshan reported to Qin Mu what happened in Mobei two months ago.

And at this moment, in the Mobei grassland in April, the spring breeze has just blown the green grass buds, located at the foot of the Buerhan Mountain at the source of the difficult river, the wolf smoke has not stopped, the battlefield is a mess, the corpses are pillowing each other, the ownerless war horse licks the owner's corpse, looks up to the sky and neighses, it looks extremely sad

Mount Bhuerhan is the place where the golden family that once swept across Eurasia rose, and is known as the sacred mountain of the Mongols.

But this sacred mountain did not shelter Gunbu, and the Tushetu Khan, the most powerful of the three tribes in Mobei, dissipated with the last wolf smoke at the foot of Buerhan Mountain;

Tushetu Khan Gunbu and his son Chahun Dorji were escorted before Zasaktu Khan Norbu, Chitat, and Tuya, and Norbu and Chitat swung their knives at the same time and cut off one of their heads.

At the moment when the blood of the headless corpse spurted out, the nearly 30,000 horses of the two tribes of Zasaktu Khan and Chitaat let out a tsunami-like cheer, resounding at the towering Buerhan Mountain.

Then, Quitat and Zasaktu Khan used the blood of Gunbu to form an alliance, formed Anda, and used the Buerhan Mountain as a witness to join forces to march south, vowing to sweep away Mo Nan and drink the Yellow River!

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PS: Brothers, the end of the month is approaching, the mountain rain is coming and the wind is full of buildings, the pressure of this month is very great, although I know that it is not easy to rush into the top six of the classification, but I am not willing to give up like this, I stayed up until half past two last night, and got a big chapter of nearly 4,000 words, please support me a lot, a qiē all depends on the brothers and sisters, kneel and beg for a monthly ticket!.

(To be continued......)