Great Tang princess

Chapter 494 Mobility

At noon, Li Yuechen stayed in the palace to eat with his mother.

Today's main course is braised lamb chops. This is not taught by Li Yuechen, but the chefs themselves. It tastes quite good.

Perhaps it was because her daughter was happier when she came back, Wu Zetian drank two more cups, took a nap after eating, and handed over the review of the memorial to Shangguan Wan'er.

After Wu Zetian fell asleep, Shangguan Wan'er came to the table and sat down, while reviewing the memorial, she asked, "How many days does Your Highness plan to stay in Dongdu?"

"I haven't returned for three years, so I have to stay for about ten days..." Li Yuechen smiled, "You should be busy in the afternoon, I will go to the barracks to see."

"Okay!" Shangguan Wan'er agreed.

After giving her a light hug, Li Yuechen turned around and left, went out from Xuanwu Gate, and went to the barracks.

When the sentinel standing guard at the gate of the barracks saw a big red figure coming on horseback, he immediately became excited, saluted and said, "Your Highness is back!"

"Yo! I haven't seen you for many years, you look a lot stronger!" Li Yuechen jumped off the horse with a smile and handed him the reins.

Most of the soldiers here were brought out by Li Yuechen himself, basically all of them can be called by name, and their attitudes are very familiar.

Stepping on the familiar road again and entering the barracks, a breeze blew in, causing the wooden sign hanging on the street tree to make a crisp sound of "clang, clang, clang" as if welcoming her back.

Li Yuechen looked up, with a smile on the corner of his mouth, walked through the straight road and entered the camp.

There hasn't been much change here. It was already finalized when it was built, and there is nothing that needs to be changed.

The soldiers were still training. When they saw the princess coming back, they didn't make a scene like a swarm. They just turned around and saluted, letting her see that they hadn't been lazy all these years and were still training hard.

Li Yuechen also raised his arms in return, and then went to the Engineering Academy, intending to see if they had brought him some surprises over the years.

After all, when I left three years ago, I left some subjects for them to study.

……

In the laboratory of the Academy of Engineering, Li Yuechen opened his eyes wide as he saw the machine making a "click" sound after adding water to the boil.

Accompanied by the white mist constantly spraying out from the surroundings, the gears in front of this pole are spinning rapidly.

This is the blueprint of the steam engine that she gave them when she left three years ago, and let them look at it for research. Unexpectedly, after three years, it was actually researched.

The expression on Wang Gangdan's face on the side was a bit smug: "Your Highness, it's a good luck not to disgrace your life, it's been done."

"Forehead……"

It's a good thing to say, but...

Li Yuechen had a complicated expression. Looking at the steam engine on the table that was not much bigger than his fist, many emotions flashed in his eyes.

It was done, it was done, and it seemed to be the case.But what about the size?
It stands to reason that making a small thing is more difficult than a big one, right?
While thinking about it, she moved her head closer, intending to take a closer look, but was stopped by Wang Gangdan's voice.

"Your Highness, it's better not to get close."

"Why?"

Wang Gangdan took two steps forward: "Your Highness, this thing is extremely unstable, and there have been many signs of explosions over the years. Fortunately, the power is not great, and no casualties have been caused. However, the boiled water vapor hit the body. It can also cause burns..."

Hearing what he said, Li Yuechen nodded to show that he understood, and planned to pick it up after stopping for a while to have a look.

And take a closer look, the small steam engine in front of you is also constantly emitting white mist, and there is also the sound of "chi chi" gas injection, which is obviously caused by insufficient sealing.

"Tell me carefully, how is this made now?"

In fact, thinking about it carefully, Wang Gangdan's original job was to make jewelry, incense burners and other small gadgets. Compared with large equipment, such small things are indeed his specialty.

And Li Yuechen also remembered that when he left, he didn't seem to mark the size on the drawings, so they didn't know how big this thing was.

It is estimated that such a model was created by mistake.

What she wants to know most now is whether this thing can be enlarged. If it can be achieved, automatic vehicles will no longer be a dream, and maybe an internal combustion engine can be developed based on this.

Cars are no longer wanted in this era, but if internal combustion engines can be developed, maybe we can really try to build trains!
The reason why I say it is an attempt is because Li Yuechen is not sure that she can make it. The engine she knows best is actually a motorcycle engine. The internal combustion engine on a train has only been seen in books and museums.

After hearing this, Wang Gangdan took her to the living room, made a cup of tea, and explained slowly.

According to him, the steam engine was made so small because the size was not marked on the drawings.

At first, I wanted to write a letter to the princess to ask, but after thinking about it carefully, maybe I didn’t write it because they knew it, so I didn’t need to write it. If I wrote a letter rashly to ask, I was afraid of being scolded.

But don't ask how big it should be?Of course, Wang Gangdan has the highest status in the Academy of Engineering here. Under his suggestion, he built such a steam engine that is not much bigger than a fist.

Originally, these small objects were his specialty, but now that he has a magnifying glass, it is much easier to make than before. In fact, Li Yuechen had already made them in the first year after he left.

But it exploded shortly after pouring the water to a boil. Thanks to its small size, the pressure in it was not enough to completely shatter the metal shell, and a crack opened.

However, the gushing high-temperature steam still scalded the arm of an apprentice. Thanks to the small amount of steam, the arm was not destroyed.

In the next two years, many improvements were made, and finally became what it is now.

Air leakage will still happen, but the chance of explosion is much lower, and the output power is not bad, even such a small gear can completely drive a grinding wheel.

After the craftsmen heard about the improvement, whether it was grinding wood or sharpening an ax in the army, they could no longer use manpower, and such a small steam engine could do it.

But the shortcomings are also obvious. There is no sealing device, and the metals are butted together entirely with the superb skills of craftsmen.

Some highly skilled craftsmen can indeed polish the metal to an almost seamless level, but this efficiency is too low.

If the steam engine is to be enlarged ten times now, the workload will almost increase exponentially.

It doesn't matter if it's just low efficiency. The big deal is to invest more and do it slowly.

However, this method cannot completely eliminate the problem of air leakage, and there are still visible air leakage.

Maybe it's not a big problem to drive a gear, but if you want to drive a carriage, the problem of air leakage is quite serious.

Besides, if there is an explosion at that time, the whole car may be gone. Li Yuechen doesn't want this kind of thing to happen.

……

After understanding the situation, Li Yuechen picked up his teacup and took a sip: "Think of a way to enlarge it a bit, and then..."

Before he finished speaking, he saw the complicated expressions on the faces of the craftsmen on the opposite side, as if they had too much to say.

"If you have something to say, just say it. I'm afraid that I will eat you up? When will you be convicted for your words?"

"Returning to Your Highness, if you want to enlarge this object, it is best to cast it in one go, and the cost is a bit high." The craftsman on the opposite side replied, "The key is..."

Li Yuechen shook his head: "It doesn't need to be too big, just take it a little bit, and try to make it twice as big next time."

As the saying goes, you can't eat hot tofu in a hurry. To be honest, even such a model steam engine has already surprised Li Yuechen.

Now that the models have been made, the rest is the problem of craftsmanship and materials. There is no way to do this, and we can only try a little bit.

So I didn't let them zoom in a lot right away, just a little bit. Anyway, technology is constantly advancing through this kind of trial and error.

This steam engine... let's say it was successfully developed...but it seems to have failed.

But in any case, this incident also strengthened Li Yuechen's idea of ​​making a generator.

Maybe such a small steam engine can't drive a generator, but it doesn't matter, there is water in the palace, and the water is stagnant, so it should be possible to make a waterwheel to make a simple hydraulic generator.

Anyway, it doesn't need much power, as long as the communication can be guaranteed, there is no need to drive any large equipment.

Let’s wait until we go to Anshan to dig more magnets. Before that, we need to push the borders out.

There are other issues here that need to be considered. It is best to have frontier troops stationed on the border. Li Yuechen's idea is to make a small reform of the tax system first, so that the frontier soldiers can also become professional soldiers.

On the current border, there are large and small garrison cities, and the soldiers inside usually have to farm and farm, and at the same time, they also have various tasks such as patrol tasks and maintaining border security.

Among these cities, some are called "city" and some are called "town". Those with a large number of frontier troops are called "army", and those with a small number of people are generally called "shouzhuo".

In small cities, because the relationship between people is relatively close and they are familiar with each other, the soldiers in these Shouzhuo cities are also called "Shouzhuo Lang" by the people.

They not only have to guard the border security, but also have important tasks such as escorting foreign missions. After a long time, foreigners will follow suit.

Li Yuechen's idea is that in the future, these frontier troops can be gathered together and become professional soldiers, so that they don't have to worry about other things and are dedicated to guarding the border.

As for reclaiming the fields, we can arrange for retired veterans to be responsible for this matter, with a clear division of labor and each performing their duties!
However, this required a high cost. Li Yuechen alone could not afford to pay so much money, so now he could only focus on minor changes to the tax system.

……

It was already afternoon after coming out of the engineering institute, Li Yuechen went back to the palace, and was going to have dinner with his mother later.

When they came to Jixian Temple, Wu Zetian had already woken up, and was sitting with Shangguan Wan'er in high spirits to play chess.

Seeing Li Yuechen coming back, Wu Zetian cast a glance: "I just went to the barracks to have a look, why do you look so happy?"

"Aniang doesn't know, there is a big surprise from the engineering institute!" Li Yuechen took a sip from the teacup in front of her without saying a word, and then went to add water on his own.

"Your Highness, it's still a servant..."

"It's okay, I'll take yours." Li Yuechen waved his hand, and directly took the pot to add water.

Wu Zetian put down a chess piece on the chessboard, and then asked, "Big surprise? You have made everything that can fly into the sky. Could it be that this time you made something that can dive into the sea?"

"Eh... That shouldn't be done within a few hundred years." Li Yuechen tilted his head and complained.

"What the hell is that?"

Li Yuechen thought for a while: "Motivation!"

"How?" Wu Zetian looked a little curious.

"Aniang, in this world, people move objects, which is called manpower; livestock pull carts and plows, which is called animal power; some farmland can be irrigated by water carts, which is called water power...all of these can Call it power! And what the Academy of Engineering is doing this time is machine power."

Shangguan Wan'er drew inferences from one instance: "Wouldn't that be called mechanical power?"

"Mechanical force!" Li Yuechen reminded, thanks to the fact that this word does not arouse any strange imagination in this era, "Simply put, the force that makes the machine move by itself can also be called mobility."

This explanation was still comprehensible, but Wu Zetian asked back: "Doesn't that mean that the carriage can move even if it is not pulled by livestock?"

"This... can't be done yet." Li Yuechen explained, "The materials and craftsmanship are still not up to par, but it will certainly be possible in the future!"

Wu Zetian nodded while looking at the chessboard: "Although it sounds a bit far-fetched, since Chen'er said yes, it must be possible."

This is the so-called inertial thinking, because she has already made something that can go to heaven, so in her opinion, although this thing sounds a bit unreliable, she still chooses to believe it.

However, Shangguan Wan'er grasped the blind spot: "Then dare to ask Your Highness, when will this thing be put into practical use?"

Li Yuechen spread his hands and shrugged regretfully: "I also want to know, but judging from the current situation, I'm afraid the road will be long and difficult..."

After all, people in this era still don't understand what the appearance of the steam engine represents, and their emotions are not as complicated as Li Yuechen's. Listening to her explanation, the two of them just felt that this thing was quite novel and looked forward to it.

But Li Yuechen's subsequent words made Wu Zetian really stop the hand that was about to place a piece on the chessboard.

"But Mom, the tax system should start to be reformed." Li Yuechen said suddenly.

Wu Zetian took back the chess piece that was about to fall, and after two seconds of silence: "Do you have a plan for this?"

"Not yet. I plan to use this period of time in the Eastern Capital to discuss with my sister and ask the household department to come up with a suitable charter."

Upon hearing the answer, Wu Zetian nodded: "Well, then write it to me when it's done!"

At the same time, she was very happy. In her opinion, this meant that her daughter had already started to learn how to be an emperor.

(End of this chapter)