Sky Curtain: My Great Qin must have an aircraft carrier!

"Oh? What did Kemin discover?"

The crowd became interested and gathered around to watch.

The paper showed a cylindrical object that looked like a lump of iron.

"Your Majesty, I just observed the celestial display and discovered a strange object."

Du Ruhui pointed to the objects in the painting, "Those Allied soldiers carried many of these iron cans with them when they marched and fought."

"I examined it carefully; they opened the tin can and took out food directly from it."

Cheng Yaojin glanced at it twice and casually interjected, "Hey, it's just a pickle jar. We Tang Dynasty soldiers also bring pickle jars when we go to war. What's so special about this?"

"Those who know their place should refrain from speaking nonsense."

Du Ruhui rolled his eyes at Cheng Yaojin, then turned to Li Shimin and said, "I have observed for a long time, and these jars are full of meat chunks. Judging from the color and texture, they are all cooked meat."

"Foreigners have come from afar, so these canned goods can last for at least a few months; otherwise, the logistics would inevitably collapse."

Cooked meat?

Sealed in a jar?

Li Shimin's eyes lit up as he figured out the key to it.

The Tang Dynasty actually had relevant sealing technologies, such as the most classic pickling jars.

However, the problem they could never solve was that the food rotted very easily without adding a lot of salt.

If the meat is cooked and then sealed with wax, wouldn't it be able to be preserved for a longer time?

Anyway, since the sky curtain gave us salt after the salt-making process, we have more salt than we can use, so it won't hurt to give it a try.

If we had canned meat, then the expedition to the Western Regions...

Li Shimin became more and more excited as he thought about it, and said in a low voice, "Have the Directorate of Works select a few skilled craftsmen to cook the meat thoroughly and seal it in earthenware jars to see if it will spoil."

"Try pork, beef, lamb, and even fish."

Fang Xuanling added, "Your Majesty, besides meat, could we also try rice and vegetables? If they can be stored for a long time, the problem of military rations will be easily solved."

"Try it! Try it all!" Li Shimin stood up, paced around the hall, and walked faster and faster.

The strength of the Tang Dynasty cavalry lay in their mobility.

But the limit to mobility is logistics; no matter how fast you run, if the food supply can't keep up, you're just running aimlessly.

If each cavalryman could carry three to five days' worth of cooked meat rations, the distance they could cover during a lightly armed raid would double.

At that time, not only the Turks, but also Tibet and Goguryeo will have to be re-evaluated.

"Kemin, you've done a great job today."

Du Ruhui cupped his hands in greeting, his lips twitched but he didn't speak.

Ultimately, the credit belongs to later generations; he merely glanced at it a few more times.

But seeing things that others can't see is a skill in itself.

-

Outside the Fengtian Hall, the sun was blazing. The white marble steps were scorching hot.

Zhu Biao bid farewell to his elderly father and turned to walk towards the Shenji Camp.

The smell of gunpowder hadn't completely dissipated from the Shenji Battalion's training ground.

Several craftsmen were squatting in a corner wiping their muskets when they saw the Crown Prince arrive. They hurriedly stood up and bowed.

Zhu Biao waved his hand and looked around.

Zhu Di was squatting in the corner, his sleeves rolled up to his elbows, holding an iron pipe and shining it at the oil lamp.

"Fourth brother."

Zhu Biao called out.

Zhu Di looked up and saw Zhu Biao standing at the door, almost dropping the iron pipe in his hand.

Zhu Di glanced behind Zhu Biao, fearing that a group of Imperial Guards might follow.

"Brother, could it be that Father Emperor sent you to deliver a message?"

"I didn't do what Emperor Yongle did! I haven't even taken up my post in my fiefdom yet, whose throne would I have usurped!"

"Alright, alright."

Zhu Biao was amused by him and raised his hand to press on Zhu Di's shoulder, "Father did not send me to settle accounts with you."

"I'm giving you a chance to redeem yourself, do you want it?"

"Yes! Of course I want it!"

Zhu Di's eyes lit up instantly, and he nodded like a chick pecking at rice.

As long as it wasn't his father's punishment, he'd be happy to do anything, even sweep the latrines, let alone atone for his crimes.

Zhu Biao took out a roll of Xuan paper from his sleeve and spread it out on the stone platform.

The paper depicts a flat, round object with an arc-shaped bottom and a small opening at the top.

The dimensions were marked in neat small characters next to it, and a cross-sectional diagram was also drawn.

"This is a water sac? What's so special about a water sac?"

Zhu Di scratched the back of his head, completely unable to figure it out.

There are plenty of these things in the army, made of sheepskin and cowhide, as many as you want. What kind of merit is this?

Zhu Biao chuckled: "Water pouches aren't unusual, but what if they were made of iron?"

Made of iron?

Zhu Di leaned closer to the blueprints again and looked at the design drawings over and over again.

At first glance, it looks similar to a water bladder, but the proportions are different; it is thinner and more compact.

"That's interesting..."

Zhu Di stroked his chin and clapped his hands forcefully. "Liu Tiezhu, Zhang Xiaolu, come here."

Two blacksmiths ran over and vigorously rubbed their hands on their aprons.

Zhu Di slapped the sheet of Xuan paper onto the workbench. "Follow this design, hammer one out with a sheet metal hammer. Can you do that?"

Liu Tiezhu squinted and examined it for a while, then grinned, revealing a few gap teeth: "It's not difficult, it's just an iron kettle."

"Just flatten the sheet metal, bend it, and weld it on. Then add a round piece at the bottom to seal it."

Just do it.

Liu Tiezhu called to his apprentices, who used pliers to cut out two thin, reddish pieces of iron. The other three took turns swinging hammers.

The sheet metal quickly took shape, being bent and rolled up, and the outline of the kettle body was already visible.

But when they got to the spout, the two blacksmiths were stumped by the blueprints.

"Your Highness, we can recreate the patterns on this cut, but it's extremely time-consuming."

"Just this one cut will probably take three to five days to heal."

Zhu Biao took the drawing and saw that it was the thread of a kettle lid.

This thing would be commonplace in later generations, but it was definitely beyond the scope of what a blacksmith could do at that time.

Zhu Biao thought for a moment and then decisively said, "Let's not do it anymore, just plug it with a wooden stopper."

"Hey, that makes things much simpler."

The blacksmiths were overjoyed and immediately made the changes.

Within a few quarters of an hour, a palm-sized iron kettle was placed in front of Zhu Biao.

Zhu Biao held it in his hand and stroked it; it was nine-tenths similar to the thing that the Eight-Nation Alliance soldiers wore on their waists.

Zhu Di watched for a while, then curled his lip and said, "Brother, this isn't much better than a leather water bag, is it?"

Zhu Biao didn't answer, but instead tossed the iron kettle over.

Zhu Di reached out and caught it, a hint of surprise flashing across his face.

"Huh, it's so light?"

Zhu Di tossed the kettle in his hand, then weighed it in his hand, his eyes wide with surprise.

That's right, because it's made of thin sheet metal, the weight is naturally not too exaggerated.

Zhu Biao smiled, pulled over a long bench and sat down: "Being lightweight is only one issue. What's the biggest problem with water bags when marching and fighting?"

Zhu Di had experience leading troops in battle, so this problem was obvious: "leaking."

To put it bluntly, a cowhide water bladder is just a sewn-up leather bag; no matter how dense the stitches are, it can't withstand sun and rain.

The cavalrymen were jolted on their backs, and the water bags rubbed against the saddle, so they would crack in no time.

Zhu Di had encountered this kind of bad luck more than once: he discovered that his water bladder had a hole halfway through a battle.

"It's good that it doesn't leak, but an iron kettle is too extravagant."

Zhu Di nodded, but he hadn't yet realized how much benefit it would bring.

Zhu Biao wasn't in a hurry. He pointed to the old leather bags on the shelf and said, "Ordinary leather bags filled with water usually go bad within a day or two, and drinking them will cause stomach upset."

"Iron is cold in nature, so as long as the water source is clean, it can be left for three to five days without any problem."

After Zhu Biao finished speaking, the entire barracks fell silent.

Zhu Di looked down at the iron kettle in his hand, his mind already in turmoil.

Yeah, how could he not have thought of that!

Lightweight and durable are secondary considerations.

The true value of an iron kettle lies in its ability to maintain water quality for an extended period of time!

The biggest challenge for the Ming Dynasty in pacifying the Northern Yuan was its water supply.

The nomadic Tartars could live by following the water and grass, while the Ming army could only rely on supplies from the rear or find puddles along the way.

With this iron kettle, how far could light cavalry travel? Eight hundred li? A thousand li?

Zhu Di's hair stood on end, and his palms began to sweat as he held the iron kettle in both hands.

"This...this is too much credit! I dare not take it for granted!"

"If Father asks, I will put my elder brother's name first."

Zhu Biao glanced at him sideways: "The name doesn't matter. As long as it can make the soldiers suffer less, that's better than anything else."

Zhu Di chuckled twice and didn't refuse any further.

A picture had already unfolded in his mind:

The Ming cavalry galloped across the northern grasslands, completely wiping out the remnants of the Northern Yuan and eliminating any further worries!