I was looking for a few craftsmen from the Ordnance Supervisor for questioning.

It was found that the main production process of the ordnance supervisor relied on forging.

And he was never responsible for the smelting of pig iron.

So basically, I didn't master any casting process.

Lu Heng was also a little helpless, so he could only start teaching them the process of pig iron smelting from scratch.

Fortunately, the process is not complicated.

It is only necessary to boil the molten iron out.

Pour it into a pre-made abrasive tool immediately.

But there are many furnaces that can burn molten iron, although there are many in the ordnance prison.

But in Lu Heng's opinion, it was too small.

It's okay to burn iron ingots and forge them into steel knives.

I want to smelt molten iron on a large scale.

That's not enough.

So the next few days.

Lu Heng almost racked his brains again and built a miniature blast furnace in the ordnance prison.

The blast furnace was built, and it was found that the coal originally used to forge iron in the ordnance prison was not working.

Because Lu Heng didn't even have to try, just smelling the smell of it burning.

I know that the sulfur content in this coal is definitely not low.

Therefore, it is worth teaching the craftsmen of the ordnance supervisor to coke first.

After tossing and turning in the ordnance prison for several days.

Lu Heng finally got his first molten iron.

As several workers poured the hot molten iron into the mold that had been prepared long ago.

Lu Heng's heart finally breathed a sigh of relief.

Although he originally sent Wu Zhao to come over.

It's more about wanting to exercise them.

But after all these things.

Lu Heng also had to admit that there were some things, he really couldn't be lazy.

Watch these craftsmen gradually become proficient in the casting process.

Lu Heng thought about it for a while, because Li Er was very active in implementing some of his ideas a few days ago.

So Lu Heng felt that maybe he should give Li Er some sweetness to taste.

Otherwise, just hanging a carrot in front of Li Er's mouth.

didn't give him a bite to eat, but I was afraid that after a long time, he wouldn't be running along.

After making a decision, Lu Heng found the craftsmen who were responsible for making molds.

Commanding them, they made a mold with an empty tube in the center and a solid mold on the outside.

Seeing Lu Heng so actively directing several craftsmen to work.

Wu Zhao couldn't help but come over curiously and asked, "Teacher, there is no such thing as this mold drawing they made." ”

"What are you doing it for?"

"What are you doing? Let someone else help us find iron ore! ”

Lu Heng's clueless answer made Wu Zhao completely confused.

A mold that looks like a big iron bucket, who can help them find iron ore?

But seeing that Lu Heng had no intention of continuing to answer at all.

Wu Zhao could only stand aside and frown and think hard.

After a few days of work in the Ordnance Prison.

At present, what dissatisfies Lu Heng the most is that the iron production of the Tang Empire is too low!

Not to mention the fine iron in the ordnance prison that can be used to forge weapons.

Even pig iron production is outrageously low.

It's like Lu Heng wants to try to produce a steam engine in front of him.

It is estimated that more than half of the iron in the treasury of the military weapons prison will not be moved.

Don't even try to make it.

It was at this time that Lu Heng understood why even if he was as strong as Han Tang.

Every time you go out to fight, you have to prepare for it years in advance.

Because if you don't prepare so long in advance, let alone the food and grass you have to eat in the war.

Even the soldiers' swords could not be produced.

So Lu Heng is now planning to build a door cannon and show it to Li Er.

Let him be willing to help him expand steel production.

After all, it is in the land of Li Erlongxing, Jindi, which has a large area of iron ore.

It's just that it hasn't been discovered or mined yet.

But in any case, since Lu Heng is now going to start working on steam engines and railways.

If the iron output of this Datang is calculated in catties, it will not be enough for him to toss.

It took a few more days to forge what was probably the first cannon in the world.

Lu Heng went straight to the imperial city.

Invite Li Er to go to the Ordnance Prison.

"I heard that you have been in the Armory Prison for more than half a month recently, and today I have come to ask me to go to the Armory Prison."

"But you made the Narausch steam engine?"

Li Er was still quite moved by Lu Heng's invitation, and asked curiously after coming to the door of the Ordnance Prison.

"It's still early days for the steam engine, but I made a good thing for my father this time, and you'll know when you go see it."

When Li Er followed Lu Heng to the place, he looked at the big hollow iron pillar in front of him.

For a moment, I couldn't help but ask a little confused, "This is the good thing you want to sacrifice to me?" Aren't you entertaining? ”

To be honest, if it weren't for the fact that it was Lu Heng standing in front of him.

At this time, Li Er estimated that he was already angry.

Because this thing in front of me looks neither beautiful nor unusual.

It can even be said that it is a little ugly.

If someone else comes, it is only strange that Li Er does not cure him of the crime of bullying the king.

Lu Heng also knew that the appearance of the cannon in front of him was really simple.

But there was no way, after all, he didn't plan to really make some very practical cannons for Li Er now.

This is just a bait to give Li Ersheng insight and make him willing to help him increase steel production.

So as long as you can fool around, then fool around.

"Father, don't worry, do you remember the artillery I told you last time?"

"This thing in front of you is artillery!"

"It's just that because it's just developed, it's still a little shabby for the time being."

Hearing the word 'artillery', Li Er's eyes suddenly lit up.

Because he still remembers what Lu Heng told him last time.

As long as you have artillery, the power of gunpowder can be increased by a hundredfold.

Unexpectedly, it has only been less than a month.

Lu Heng had actually built the artillery!

After learning that the thing in front of him was artillery, Li Shimin's gaze suddenly changed.

Even the potholes left behind by casting in clay molds seem to have a unique beauty.

"Hurry up, show me how to use your artillery!"

With Li Shimin's eagerness to order, Lu Heng also asked people to bring over the three cannonballs that were cast together yesterday

"Father, this thing is called a cannonball, and its relationship with this cannon is like a bow and arrow."

After Lu Heng finished introducing, he picked up a packet of black powder wrapped in silk from the plate on the other side.

Silk is the most suitable thing for gunpowder that Lu Heng has tried now.

Because after it burns, there is hardly any residue.

Therefore, it can be used as a fixed charge for artillery.

"This is gunpowder, father, you already know it."

"And now, we just need to put this bag of gunpowder into the cannon first, compact it, and then put the shells in it."

Lu Heng commanded his entourage to reload.

While explaining to Li Er.

After completing the loading of the gun.

Lu Heng took a wooden skewer and poked a small eye on the ignition port reserved on the artillery.

A lead made of gunpowder and hemp rope was put in.

Only then did he say to Li Er: "Father, this cannon is loaded." ”

"Just light the fuse and fire for a moment."

After Lu Heng finished speaking, he first pulled Li Er back more than ten meters.

Only then did one of his attendants go to a distant fire and light a torch, ready to light the fuse.

After all, this cannon had just been made, and the amount of charge was also estimated by Lu Heng.

If it blows up at that time, it will be too cost-effective to lose both him and Li Er in it.

When everything was ready, under Lu Heng's signal, Li Er ordered: "Ignite!" ”

As Li Er's order was given, the entourage with the torch hurriedly lit the fuse.

Then immediately ran to the side without looking back according to Lu Heng's explanation.

With the fuse that Lu Heng deliberately left long, it slowly burned into the artillery.

"Bang!" After a loud bang.

The shells in the artillery made a black trajectory in the air.

Then he disappeared from everyone's sight.