Playing intrigue is worse than engaging in infrastructure

"Your Highness, don't we wait for Gerile to withdraw?" Dan Renji raised his head and asked.

What if when they left with the Xuanjia Army, the Zig tribe was killed by Gerile?

"You still look like Geril's army just rebelled a few days ago? You can rest assured."

Song Qingyuan shook his head with a smile, glanced at the direction of Mount Qi, and continued: "But tomorrow, Gerile will return to the west of Mount Qi with a few thousand remnants of his soldiers."

Although Gerile is ambitious, he doesn't have the corresponding ability to support him. He is grumpy and self-willed, and he treats the counselors around him as air.

He alone can't make any big waves.

Dan Renji let out an "oh" in a daze, obviously accepting Song Qingyuan's statement, turned around and left, and prepared to lead the troops back to the royal court tomorrow.

The reason why Song Qingyuan was in a hurry to return to the royal court was that apart from Gerile's failure to make any trouble, there was another very important reason, and that was that the duration of their trip had already exceeded the originally expected five days.

Although he was more at ease in entrusting Da Lantai with his daily business, and if any emergency happened, Wang Ting would definitely contact him immediately, but Song Qingyuan was still thinking about it these days.

After all, Lian Ti's attack was reaching a critical stage.

The last residence report showed that Lian Ti had divided the army into three groups and then joined forces in Suining before concentrating on attacking Tongzhou.

Once Tongzhou was broken, there would be no natural danger in the Southern Zhou Dynasty to resist Mobei's iron cavalry.

At this time, Song Qingyuan must sit in the royal court.

When they returned to the royal court, they had a lot less raw materials for making gunpowder barrels than when they came, so it took half a day less than before.

Because Song Qingyuan told Jiang Duo when he was leaving that no matter who came, he would refuse on the grounds that he was sick in bed and it was inconvenient to see guests.Therefore, after he came back, he had to continue pretending to be sick for a few days.

During the few days when he first arrived at the royal court, Song Qingyuan stayed in the study room, checking the daily records of Dalan Terrace, which were similar to work reports, and tried his best to act out the drama that his body gradually improved for a few days.

Finally, when it was almost time to go out, Song Qingyuan received an urgent letter from Amur.

The letter said that heavy fog often appeared in the mountains in the past few days, and several caravans who wanted to go to the Southern Zhou Dynasty were discouraged.

Afraid of getting lost in the mountains, they either decided to divert their route, or stopped at Muhe Tribe, intending to wait a few days before leaving.

And Amur's letter was worried that the fog in the mountains would affect the follow-up supply of supplies and food, and asked Song Qingyuan if he wanted to send an army to deliver supplies a few days in advance.

After reading the letter, Song Qingyuan frowned and sat back at the desk, thinking about this question while pinching the edge of the letter subconsciously.

When they were in the Zig tribe, they encountered a similar situation.

The air humidity was high in the morning, and Dan Renji specially delayed the time of making the gunpowder barrel, for fear that the gunpowder would become damp and lose its effect.

The past few days are in the rainy season in Mobei, the air is rich in water vapor, and the temperature difference between day and night in the mountains is large, so it is indeed prone to heavy fog.

Song Qingyuan hadn't paid attention to this problem before, but now that Amur reminded him, he realized that the thick fog would bring great trouble to the army's march.

Regardless of whether the marching speed of the supply army is greatly slowed down, or even lost its way directly in the mountains, it will have a great impact on the soldiers fighting on the front line.

Seeing that Song Qingyuan remained silent after reading the letter, Da Lantai couldn't help asking, "Your Highness, what's the problem?"

Song Qingyuan handed the letter to Jiang Duo who was behind him, asked him to hand it to Da Lantai, turned to the lieutenant general beside him and asked, "If you encountered heavy fog during the march, what would you usually do?"

The lieutenant lowered his head and thought for a while before replying: "If a scout detects that there is heavy fog ahead, most of the time they will choose to take a detour. Because marching in the fog, it is easy to get lost."

"What if it's inconvenient to change lanes?" Song Qingyuan asked again.

"If it's inconvenient to change the route..." the lieutenant general said after deliberation: "Then we will first send out a scout army to explore the road, and then make marks along the way, and the army will march along the marks. But in this way, the speed of the march will be reduced. It will slow down a lot."

"Would it be better if we could see the direction clearly in the fog?" Song Qingyuan thought.

Although the deputy general didn't know how to identify the direction in the thick fog, he still replied seriously: "If you can identify the direction and have a topographic map, the possibility of getting lost will be greatly reduced, and the marching speed will not be affected."

"I understand." Song Qingyuan nodded.

Just when Da Lantai finished reading the letter, he asked, "Your Highness, can you tell the direction in the fog?"

Seeing that Song Qingyuan's expression was not in a hurry, Dalantai only thought that he already had a way to deal with this matter, and looked at him expectantly.

But Song Qingyuan didn't immediately order them to do things like before, but looked at the lieutenant with some hesitation, "Didn't you bring something to indicate the direction when you were marching?"

He clearly remembered that things like the compass appeared very early.

There was Sinan as early as the Warring States period, but why did they look like they had no tools to tell the direction.

Song Qingyuan still remembered the crisp and sweet apples he saw in Yanyun, which should have appeared after the American missionaries came to China.

After all, this is a parallel world, what if there is no compass, or even a lodestone?

But fortunately, this world did not deviate too much from the ancient times that Song Qingyuan was familiar with. The deputy general was stunned for a moment and asked, "Your Highness is talking about the compass car?"

Song Qingyuan nodded suspiciously.

Isn't this Sinan who can tell the direction?How can you still get lost in the fog?

Xu Shi understood the doubts in Song Qingyuan's eyes, and Dalantai took the initiative to explain: "Your Highness, you don't know that the compass car is huge and heavy, and it is not convenient to carry it when marching in the mountains. It only needs to go through the Gobi or In the desert, the compass car will be used."

Song Qingyuan's impression of the ancient compass is still the one restored by later generations, which is composed of a square copper plate with directions engraved on it and a spoon-shaped magnet.

But that thing had never been unearthed, and the compass car described by the adjutant had nothing to do with the Sinan he knew.

Sculpted into a spoon-shaped magnet, the spherical bottom will greatly reduce friction and lower the center of gravity. If it is equipped with a smooth enough surface, it should indeed be used to indicate the direction.

However, Song Qingyuan still felt that if the magnet was made into the shape of a spoon, it would not only require a magnet with extremely strong magnetism, but also require a lot of polishing effort, which is really not cost-effective.

Still a magnet.

Thinking of this, he still ordered people to prepare a lot of magnets, and asked the craftsmen to make magnetic needles one by one.

Looking at the magnetic needle in front of him, which was many times smaller than the magnetic spoon, Song Qingyuan was very satisfied.

In this way, people who are away from home can just put it in their arms, and it is much more convenient to identify the direction.

But soon, Song Qingyuan realized another problem.

A question directly related to whether the compass can be successfully manufactured.

That's how the magnetic needle can be erected so that it can rotate flexibly in the horizontal direction.

Song Qingyuan suddenly remembered that most compass of later generations made a magnet that can indicate the direction into a rhombus-shaped sheet, and then a thin needle was erected on the bottom bracket to support the above magnetic sheet so that it could rotate freely.

But now that he has ground the magnet into a needle shape, how can he set it up?

Song Qingyuan looked at the magnetic needle as thick as a sewing needle in front of him, and fell into a rare silence.

The name Compass misunderstood him too deeply!

So much so that when Song Qingyuan thought of the compass, he subconsciously made it into a needle shape.

How can a magnetic needle that cannot rotate flexibly indicate the direction?Song Qingyuan was at a loss for a moment.

This time is spent on the craftsmen polishing the magnetic needle. If it is overturned and redone, the original hard work will be wasted. The most important thing is that they may not have enough time.

Song Qingyuan planned to make two-handed preparations, while asking the craftsmen to step up making diamond-shaped magnetic pieces, while thinking about how to use the existing magnetic needles.

In short, the hard work of the past few days must not be in vain!

While the craftsmen were working overtime to make the second-generation compass, Song Qingyuan suddenly remembered that Shen Kuo's "Mengxi Bi Tan" seemed to record several methods of making the compass.

The book mainly introduces four methods.

The first is the water float method, which uses the buoyancy of water to suspend the magnetic needle on the water surface to indicate the direction, which is similar to the principle of the compass used by people when sailing.

The second and third methods are relatively similar, and they all place the magnetic needle on a relatively smooth place to indicate the direction, such as a fingernail or the edge of a bowl.

But these two methods were ruled out by Song Qingyuan immediately.

The main reason is that although this method can levitate the magnetic needle, it is still not convenient enough.

Just imagine, when the army is marching, it is necessary to find a stable and windless place, and take out a large bowl to let the magnetic needle levitate.

If one is not careful and the magnetic needle falls into the grass, it is not known whether such a small needle can be found.

Song Qingyuan felt a headache just thinking about that scene.Moreover, the direction indicated by this method is not accurate enough.

As for the last method, which Shen Kuo highly recommends, it is to stick a very thin silk in the middle of the magnetic needle and hang it in the air to indicate the direction.

The accuracy of this method is not bad, but it is also not suitable for use on the march.What if the wind blows one day and you need directions?

Besides, judging from the climate in Mobei, such a situation is the norm.

Now we can only hope for the speed and water compass made by craftsmen.

Song Qingyuan drew the shape of a water compass on the picture, a circular disk with smooth sides and a concave center.

At that time, fill the middle with water, and then suspend the magnetic needle in the water, which can be used to identify the direction.If you are worried that the water inside will spill out during the march, you can also add a transparent cover on it.

The few jade cutters who made the telescope lens before had already had a lot of experience in polishing crystal chips, and it would not take too much time to polish a simpler flat mirror.

Although crystals are a bit more expensive, if the compass of later generations cannot be made tomorrow, Song Qingyuan can only support a few crystals of excellent quality in friendship.

In short, before the soldiers transporting grain and grass set off, he had to make a compass.

In a certain side hall of the palace these days, the sound of ding ding dong dong can be heard from time to time, that is Song Qingyuan leading craftsmen to make a compass.

As for why he didn't make it outside, it is of course because Song Qingyuan still has a "healing from the wind and cold" character design, so it is inconvenient to travel between the workshop and the palace every day.

What's more, since Lian Ti led the troops to the expedition, only Song Qingyuan's palace is left in the huge Mobei palace, and the other places are empty and empty, so it's better to use it as his workshop.

The author says:

Song Qingyuan: The black in front of you is not black, and the compass you mentioned is not a needle.

Anthracene, there is really no real thing unearthed from Sinan, and it's hard to say whether it's even a spoon...