Yan Fa immediately asked the question that had been in his mind, "Sir, this hydrogen is lighter than air and can make the airship rise, but how to make him go down?" ”

"Oh, I know this, you just let go of a few air bags, it's the same as turning off the fire in a hot air balloon." Gan Shi immediately answered, and looked at Yan Fa after speaking, with an expression of how stupid your head is after studying for so long.

Ma Qiang nodded and said, "What Gan Daochang said is indeed a method, but there is another way, which is called the "air room".

First of all, you should all know what atmospheric pressure is, as the altitude increases, the atmospheric pressure gradually decreases, then the hydrogen in the capsule will expand, if all the air sacs are filled with hydrogen, then in the air, it will inevitably expand to crack.

Therefore, the airbag can not be filled too much first, and a certain elastic space needs to be left, and secondly, a part of the airbag needs to be left, which is best designed as the way of the inner and outer capsules, the inner is the air bag, and the outer is the hydrogen bag, and then the gas ratio of the two airbags can be used to adjust the rise or fall.

In fact, this is not only true in the sky, but also underwater. ”

Another application of air room technology is submarines, but this is even less practical for Ma Qiang.

Who is he going to hit with a submarine? Ao Guang or Poseidon?

The night passed quickly, and at dawn, the battle report from Fushan was that three of the eight military forts had been breached, and Yuan Shao seemed to be running out of gunpowder, so he did not bomb it like this, but changed to a siege.

Call...

Just don't have enough gunpowder.

- Under the mountain

Yuan Shao looked at the list in his hand, and only felt a faint pain in his heart.

In one night, almost 4,000 catties of gunpowder were used.

It was quite refreshing to listen to the explosion before, but now I know that where is the explosion, this is the sound of the money in the water.

It's all money!

Why don't you say these people don't know how to save points!

"Ming Gong, although this gunpowder is good, the consumption is too great, there are a few military forts left, let's use the digger army." Xu You stepped forward to persuade him, and by the way, he gave Yuan Shao a step.

Yuan Shao coughed lightly and snorted, "The heads of those thieves are divided into two groups, and they are lined up in front of the Fushan Military Village and outside Yecheng, so that these thieves know the fate of resisting the heavenly soldiers!" ”

"No!"

Intimidating enemy troops with their heads, a common practice in ancient armies, no one felt that there was anything wrong with it.

"Yang Feng!"

"In!"

"You lead five thousand elite horsemen to investigate the enemy's situation around, and by the way take a look at the situation of the farmland, I watched the wheat ripen on the road in these two days, but it was cheaper for us."

"No!"

"Other generals, set up camp and repair, and attack Fushan tomorrow!"

"No!"

"That's... Ziyuan, you and I will come on a trip. ”

Xu You responded with a smile, regardless of the frustration with a cold face on the side, and followed Yuan Shao to the back.

Frustrated Zhu looked at Xu You's face, and couldn't help but miss his good friend Tian Feng.

I don't know what happened to him.

After the account, Yuan Shao said to Xu You, "If it weren't for the actual battle, I didn't know that this gunpowder was so useless, Ziyuan, you have to go back to Taiyuan to supervise the manufacture of gunpowder, at least 200,000 catties must be prepared, otherwise I will not have enough confidence in this battle..."

200,000 catties, in fact, is not much, only about 50 tons.

In the afterlife, an overloaded truck is alive!

But in the late Han Dynasty, in the era of handicraft workshops, a certain amount of productivity was still needed.

Xu You also knew that this matter was very important, and responded, although he could not make meritorious contributions on the front line, if this matter was done well, it would not be less meritorious than on the front line.

"By the way, there is still grain and grass, I asked my son Yuan Xi to guard in Shexian County, he is young and ignorant, you go to Shexian County to check more, don't make any mistakes."

Yuan Shao had four sons, the eldest son Yuan Tan, the second son Yuan Xi, the third son Yuan Shang, and the youngest son Yuan Mai.

Probably because he didn't get the love of his family when he was young, Yuan Shao attaches great importance to his family, and he works hard for his sons, and he trains them well.

Don't think it's a mistake for Yuan Shao to reuse his sons, this matter needs to be seen from the perspective of the time, didn't Cao Cao also use a large number of generals of the Cao family and the Xiahou family, everyone is nepotism, because in that troubled era, only these relatives are the most reliable people.

If you want to say what Yuan Shao was wrong, it is probably because he lost the battle of Guandu.

Otherwise, the comments of future generations on him will inevitably be a different situation.

Xu You listened to Yuan Shao's words and knew that Yuan Shao was worried about grain and grass, so he smiled and comforted, "Our army's grain and grass are hoarded in Shexian County, surrounded by lofty mountains and mountains, and it is difficult for mountain people to cross, let alone the army."

No matter how strong his horse is, is it possible to fly? ”

The corners of Yuan Shao's mouth twitched.

Aren't you able to fly, have you forgotten about Gongsun Zhan?

But he also understands that what kind of ball can only sit two or three people, if two or three people burn Shexian County, then he himself will kill his relatives and cut off this unlucky second child!

Here, Yuan Shao asked Xu You to go back and ask for gunpowder, and Ma Qiang over there began to review the new firearms.

But after checking it out, Ma Qiang found that compared with half a year ago, whether it was muskets or artillery, there was no big improvement.

"Brother Xiaoma, do I think the road of black powder has come to an end?" Yue Yang looked at Ma Qiang, who was frowning, and asked tentatively.

"The potential of black powder is really not great... Okay, you wait, I'll call a few gunpowder engineers to work on the upgrade with me. ”

"Little Brother Pony, which glycerin should you use?"

"No, that thing is too unstable, the army uses that kind of weapon, how can you let the sergeant fight with peace of mind?"

Even nitroglycerin with all kinds of sundries will be in danger of seeping out under damp or pressure, which will eventually lead to an explosion, and these weapons of the army are stored in warehouses most of the time, Ma Qiang does not want to worry about which of his arsenals will explode again every day in the future.

While thinking about improving gunpowder, Ma Qiang took the independent division on the road of being a bait.

Just when the two armies of Yuan and Ma on the front line of Taihang Mountain were fighting into a pot of porridge, Henan, with Yanzhou as the core, also officially began the autumn melee.

First of all, Cao Cao issued a document questioning Tao Qian's three major crimes from October 1, the first crime was not being able to fight against Dong, the second crime was self-proclaimed official position, and the third crime was attacking and killing his colleagues, and then he raised troops to attack Xu.

Well, although Cao Song is retired, he can be regarded as a colleague.

As soon as Cao Cao sent troops, Tao Qian, who had been guarding against Cao Cao, immediately got the news, and then Xuzhou Mu, who was a lot older, immediately grabbed the life-saving straw Lu Zhi and offered his sword, and Lu Zhi was fully responsible for the deployment of this battle.

Lu Zhi also knew that the situation was urgent, and ordered Liu Bei's three brothers to immediately raise troops from Xiaopei, and he took Cao Bao, Zang Ba and other Xuzhou soldiers and horses to Langya to meet the battle.

The Second Battle of Yanxu officially broke out.