"Mr. Yu, bring me your compass."

Wu Liang did not rush to a conclusion, but turned back to Ji and said.

"it's here."

Yu Ji quickly took the compass out of the bag and handed it over.

After Wu Liang took the compass, he straightened it and looked at it. He saw that the compass in the middle of the compass still could not indicate the correct direction at this moment, but was still pointing in the direction of the holy mountain.

Then he slowly approached the bronze statue in front of him while holding the compass, while observing the changes of the compass.

At first there was no change in the north needle on the compass.

After the compass had rested on the bronze statue, the compass seemed to be shaking slightly, as if there were two forces coming from different directions wrestling with each other.

Wu Liang gently moved the compass with his finger, causing it to rotate slowly.

And when the compass stopped completely, it was pointing to the bronze statue in front of it...

At this moment, Wu Liang had already come to the conclusion:

There is a high probability that the black material in this stone statue is the highly magnetic basalt on the Holy Mountain;

Or even if it is not a strongly magnetic basalt, it should be an ore with extremely high metal content, and the metal rich in it should most likely be iron, because the material used in this compass is a magnet, and there are only so many metals that can produce gravity.

There are several types, among which iron can be produced naturally and has the largest amount in nature!

As for the pure pure copper on the surface of the bronze statue, it will not have any impact on the compass, so there is no need to consider this interference at all.

In fact, magnet is also closely related to iron, and its composition is ferric oxide.

Therefore, whether this black material is the highly magnetic basalt on the holy mountain or an ore with extremely high iron content, it is not unrelated to iron, and the two do not actually conflict. Basalt can contain iron tetroxide and can also contain iron.

Extremely high ore, everything is determined by nature.

So... iron... elemental copper...

Wu Liang suddenly thought of an even more incredible possibility - wet copper smelting!

This copper smelting method first appeared in the "Huainan Wanbi Shu" written in the Western Han Dynasty. The sentence "Zeng Qing obtained iron and turned it into copper" records the chemical phenomenon of wet copper smelting.

As far as Wu Liang knows, wet copper smelting was truly utilized and put into production in a systematic manner in the Song Dynasty, nearly a thousand years after the end of the Han Dynasty.

Before that, fire-based copper smelting technology had always been the mainstream.

In fact, you can tell the difference between the two copper smelting technologies by listening to their names.

As the name suggests, pyrometallurgical copper smelting actually involves using intense fire to smelt copper-rich refined copper ore, thereby refining the copper metal in it. It is not much different from the blast furnace used for iron smelting.

Although this copper smelting method is simple and straightforward, the biggest problem is that it can only be used for copper-rich ores.

Hydrometallurgical copper smelting is a chemical copper smelting method. The refined copper ore in nature is usually copper sulfide. When copper sulfide is weathered and oxidized in nature, it will gradually transform into copper sulfate, which is often called among the people.

Bile alum and copper sulfate are soluble in water. After completely dissolving the impurities and removing the impurities, bile alum water can be obtained. When iron is immersed in the bile alum water and fully reacted, the copper ions in the copper sulfate can be replaced, thereby forming extremely

Pure elemental copper.

The metallic copper extracted by this copper smelting method has extremely high purity, is easy to operate, and saves fuel. Most importantly, this method can be used for lean ores, rich ores, sulfide ores and oxidized ores, and its scope of application

Very broad.

In comparison, wet copper smelting is naturally more advanced.

After all, later studies have shown that the copper content on the earth is only about 0.01%. Refined copper ore suitable for fire-based copper smelting is even rarer and is a non-renewable mineral resource. Iron, also a commonly used metal, accounts for 5.1%.

, in such comparison, copper appears to be very rare, and naturally more efficient copper smelting technology must be adopted.

For this reason, wet copper smelting officially became the main copper smelting method in the Song Dynasty, and it has continued into later generations. Even before Wu Liang traveled through time, wet copper smelting was still the mainstream method of copper smelting.

so……

A more intense look of shock appeared in Wu Liang's eyes.

The sight of simple copper and black matter fused together, and the structure of the statue that doesn’t look like a simple copper plating process, coupled with the basalt that may also have a high iron content...

If this is really a relic of the Jiuli Kingdom from ancient times, and the copper smelting technology mastered by the Jiuli Kingdom is wet copper smelting, then wouldn’t it mean that his previous speculation had greatly underestimated the Jiuli Kingdom?

The copper smelting skills of the Zhou Dynasty are not comparable to those of the Zhou Dynasty, but can be compared with the later Song Dynasty?!

This is only a comparison within the scope of the Chinese dynasty. If compared with the West... it is almost equivalent to being ahead of the entire human history and civilization. After all, the West only began to use hydrometallurgical copper smelting at the end of the 17th century. By the end of the 17th century, it was almost ready.

It has reached the scope of modern times.

"This... what exactly did the young master discover?"

Seeing Wu Liang's expression gradually turn from confusion to shock, everyone in the Hu army who was waiting for Wu Liang's conclusion was filled with surprise.

Although they didn't know anything about wet copper smelting, they knew Wu Liang. If he hadn't made some shocking discovery, he would definitely not show such an expression based on his knowledge.

Under everyone's surprised gaze, he finally came to his senses.

However, he did not immediately speak out the speculation in his heart, because this speculation needed more evidence to support it, at least the current evidence was not enough.

The most direct evidence is bile alum water.

This is the raw material that can never be used for copper wet smelting. This water is blue and was even used as a pigment in ancient times. Therefore, if wet copper smelting was used in this place, there will inevitably be blue water that cannot be removed.

Only if he could find traces of sex could he confirm his guess.

Of course, it is also possible that this place is not a hydrometallurgical copper mine at all, and Wu Liang was unable to find what he suspected might exist.

If so, he could only choose to take this bronze statue back and study it slowly...if he could get out of this place alive.

…

Wu Liang did not explain, and no one in the Hu army asked any further questions.

This matter was temporarily shelved amid everyone's curiosity.

Excavation work continues.

This time, in order to speed up the excavation progress, the Hu army did not stop work and rest after dark, but continued to work until midnight by the light of the bonfire lit at the excavation site.

During dinner at night, Bai Jingjing quietly approached Wu Liang, pulled him to a deserted place and said with a serious expression: "Wu Youcai, we probably have enough left to eat for another day. If there is no way to leave here after that,

, everyone is probably going to start to suffer from famine, so I want to ask you, do you have any solution?"

"No."

Wu Liang shook his head very bluntly.

"Then what are your plans?"

Bai Jingjing asked again.

"I just asked Yang Wanli privately. The repair work of the three gatehouses has been basically completed. However, after the repairs, the gatehouses can no longer enter or leave the secret realm. I'm afraid this road will be impassable."

Wu Liang pondered and said, "The only hope now is that kind of strange insect. If we can find that kind of strange insect in the river bed and find a way for them to enter and exit the secret realm, there may be a glimmer of hope..."

"So do you think this method has a good chance?"

Bai Jingjing asked again.

"Hard to say……"

Wu Liang shrugged and said with an ambiguous bitter smile.

"In that case..."

Bai Jingjing's expression didn't change much when she heard this, but she stretched out her hand in front of Wu Liang's eyes, "Why don't you return the Suihou Pearl to me in advance? This is the mission entrusted to me by the ancestors of the Bai family. If it ends up being

I must die here, even if I can't bring the Suihou Pearl back to the Bai family with my own hands, I still hope that the Suihou Pearl will be in my hands when I die."

"So heartless?"

Wu Liang was slightly startled, "I'm not dead yet, and you're starting to make arrangements to salute. Are you the second senior brother?"

"What second senior brother?"

Bai Jingjing looked suspicious, but she didn't pursue this weird statement. Instead, she suddenly showed a sly smile and said, "I'm relieved that you don't want to return the Suihou Pearl. I'll go and rest first."

"???"

Wu Liang's face was immediately full of questions.

Unexpectedly, Bai Jingjing finally broke the mold and would use such a method to test his tone and will.

But he really doesn't have any clue now, he just doesn't want to give up easily until the last moment... Bai Jingjing has indeed figured out his pulse. If he has the idea of ​​giving up in his heart, he will indeed take the initiative to follow him.

Hou Zhu is returned.

…

The next day.

Although the Hu army enlarged and deepened the hole a lot, the result was not good.

Apart from digging out a few tattered pottery pieces in the red soil that were hard to tell from the time of manufacture, Wu Liang didn't get anything of archaeological value, and naturally didn't get any clues that might help them get out of here.

However, during this day, their food consumption was not spared because the excavation work made no progress.

At night, the food eaten by everyone in the Hu army was the last reserve.

Maybe there was still a little left, which could barely cope with the morning meal the next day, and then they would really only have the three little wild boars and the big rooster left.
To be continued...