In my dream of returning to the Tang Dynasty, I snatched Wu Zetian from my lap.

He covered his head with his hands, curled up in the trench, and dared not raise his head.

One second, two seconds, three seconds... He could even smell the pungent odor of gunpowder being lit and then fired, but he still didn't hear the sound.

Li Yuanchang slowly opened his tightly closed eyes, loosened his hands, and cautiously sensed what was above him.

Twenty breaths passed, and it still hadn't exploded. Li Yuanchang's heart sank to the bottom. He slowly got up and cautiously peeked out with his eyes.

The earthenware pot, which had been pressed down by the stone slab, was still there. It hadn't exploded at all; it was just emitting wisps of smoke and flames, making a soft hissing sound.

Dud!

Two words popped into Li Yuanchang's mind, and his heart, which had sunk to the bottom, recovered a little.

This suggests that the black powder itself is likely fine; the problem must lie elsewhere.

He didn't rush to get closer. Instead, he waited until the flames and black smoke inside the pot had completely dissipated and the temperature had dropped before finding a stick and smashing the pot.

A strong, pungent smell spread out; it was the familiar smell of gunpowder, which excited people.

But for some reason, it didn't unleash any power at all.

Li Yuanchang picked it up and examined it carefully. The black powder inside had been completely burned out, and there was no sign of it failing to ignite.

He frowned, trying hard to recall all the knowledge from his previous life.

Suddenly, his eyes lit up.

"It seems that black powder needs to be ignited in a sealed container to instantly burn and generate pressure, ultimately leading to an explosion. If air gets in, it seems it will just burn up with a 'whoosh' like before!"

He muttered to himself, then examined it carefully and finally confirmed it!

"It must not have been sealed properly!" He squeezed the soil that had been used to seal it not long ago. It was too dry, with many gaps, allowing a lot of air to circulate.

"Damn it!"

He cursed, "Two pounds of gunpowder wasted for nothing!"

He then quickly sought a solution. He found more clay, a type of clay similar to Guanyin clay, which was softer in texture. He added some water, pressed it down, and sealed the earthenware pot.

This does indeed isolate the soil from the air, but it creates another technical problem: the soil is very easy to detach, making long-distance transportation impossible.

Not to mention military operations, where soldiers are constantly jostled on horseback.

In ancient times, there were no plastic or rubber products, and rubber was not produced in the Liao River area during the season. There was no substitute for rubber in the surrounding area.

Just when it seemed like it was about to be completed, the invention of gunpowder was once again in trouble.

Without a good enough seal, a grenade is nothing more than a firework!

Li Yuanchang racked his brains and tried various methods, but still couldn't solve the problem.

He could only issue an order for the entire army to work together to find a way to ensure both sealing and high strength stability by using local materials.

Three whole days have passed in the blink of an eye!

Li Yuanchang, west of the Liao River, tried every possible method, even considering fishing and using fish glue as a seal for connecting the outer shell.

However, this method would increase the workload unimaginably and make the process more complicated, so it was ultimately abandoned because it could not be implemented.

Just when he was at his wit's end and was about to send a message back to Liangzhou by carrier pigeon, asking Wang Hongzhi to gather the members of the Chamber of Commerce to find a solution,

Suddenly, a turning point appeared!

A horse archer in the army, who had worked as a bricklayer in his youth, offered Li Yuanchang a solution: "lime and tung oil paste"!

This is one of the oldest methods of sealing gaps used by the Han people.

Moreover, both lime and tung oil are readily available at present. The army has tung oil and carries it in battle.

Lime, on the other hand, happens to be abundant in the mountains of Liaodong.

Having obtained this method, Li Yuanchang quickly implemented it.

Upon testing, it was discovered that this paste is not only strong and can block air, but also has extremely strong waterproof properties.

The critical technical problem that had been holding them back was overcome in an instant.

Li Yuanchang was extremely excited. On the spot, he promoted the archer who came up with the solution by one rank and gave him a reward of thirty strings of cash, which he then sent directly back to his home.

He then completed his second attempt as quickly as possible, using lime and tung oil paste to seal the earthenware jar.

This time, he went all out, pouring all eight pounds of finished gunpowder into it to create an oversized hand grenade.

Chi Chi Chi!

As the fuse was lit, it was improved this time, with a burning speed that was more normal and an extended time of at least ten breaths.

Li Yuanchang jumped into the deep pit, yelling, "Everyone lie down! Lie down!!"

He shouted himself hoarse.

The soldiers who gathered around to observe were all bewildered, but they all did as instructed. Those who were closer jumped into the trench, while those who were farther away lay down on the ground.

Their eyes were filled with astonishment, not understanding what was happening, and they stared wide-eyed at the center of the field.

There, the fuse was hissing and emitting blue smoke, giving off a strong smell of gunpowder.

At that moment, they had no idea what was about to happen.

Until, bang!!

An earth-shaking explosion resounded, like a thunderclap, causing countless soldiers to tremble!

The flames spewed out like a giant python, and the enormous impact directly overturned the stone slab weighing dozens of kilograms, tearing it apart instantly!

The massive shockwave shook the ground, snapped many tree branches, and caused the warhorses in the distance to neigh in unease.

This scene was reflected in the pupils of countless soldiers, causing their pupils to dilate, their hearts to race, and their minds to be gripped by extreme fear.

A plume of blue smoke billowed into the sky, followed by a downpour of sand and gravel that fell on the heads of the soldiers on the ground.

The epicenter of the explosion was shrouded in thick fog, making it difficult to see clearly.

Dead silence. The entire hall was deathly silent.

At the martial arts training ground a kilometer away, countless people exclaimed in surprise, "What's that commotion?"

"What's that noise?"

"The mountain collapsed?!"

"Or is it heavenly lightning??"

Screams erupted, and everyone felt threatened.

This is not just a human instinctive reaction, but also a natural fear of the unknown thunder.

Whether it was nomadic peoples or the Central Plains civilization, in ancient times, such a huge explosion sound was a source of terror for the soul.

Because they couldn't explain it, they often attributed this phenomenon to "divine punishment from heaven"!

"Cough cough cough!!"

A violent coughing sound came from the trench.

Li Yuanchang staggered to his feet, his ears ringing, his head covered in pebbles and dirt, but this could not conceal his ecstasy.

The first human-made hand grenade has been successfully tested!

He climbed up, staring at the huge, deep pit that was gradually becoming clearer beneath the blue smoke, and ran wildly, shouting and laughing like a madman.

When he got excited, he even jumped around with his hands and feet.

"Hahahaha, it's done! It's done!!"