Gu Guo had never seen what the actual stove looked like in real life, but from the black-and-white cross-sectional drawing in his memory, it could be inferred that it was roughly like a flower pot used as a potted plant, wide at the top and narrow at the bottom.

Digging a rectangular pit down at the selected site, he estimated the size of the furnace, and hundreds of thousands of people could not use that much capacity for the time being, so he decided to dig a pit two meters long, one meter wide, five meters deep, and one meter deep.

Use firewood to dry the damp soil in the pit and spread the plant ash at the bottom of the hole, the plant ash can effectively absorb the moisture in the soil. The bottom is then flattened with stones and bricks are formally laid on top.

The whole process took Gu Guo and others two days, and without the help of metal tools, digging the pit was very fatal, especially digging a one-meter-deep pit. Feeling back to the time when he was building a house and digging in the earth, he couldn't help asking, "Goo, are we going to build a new house?" ”

"We're going to build a new stove!"

Gu Guo replied that he took the birch at the bottom of the pit and handed it over, and the mud bricks fired from clay were neatly laid at the bottom of the pit one by one with lime and mortar as a binder.

"A new stove? Is it to burn a larger clay pot? ”

"This time we don't burn pottery, we burn stones!"

"Burn stones, what can you do?" Camelina scratched his head, not knowing why.

Hua was suddenly enlightened, and he remembered that before the people went back to the cave, they had gone to the foot of a red mountain and dug up many red stones.

"Are you going to burn those red stones?" Birch asked, but he couldn't figure out what there was to burn the stone, not to eat it, and not to hold it like pottery.

Gu Guo nodded, he didn't explain too much, because he couldn't talk about the advantages of metal copper in the current environment.

Pure copper is too soft to be used as a material for sharp tools such as axes and knives, and it is not even as hard as stone, but when tin is added to copper, a copper-tin alloy is formed, which is known as bronze.

Gu Guo kept in mind several classic formulas of bronze, such as those used to make gears and bearings, one tin, zinc and one lead, and the copper is seventeen wear-resistant bronze, and the gun copper used to make cannon barrels......

Of course, he can only make up these finished products in his mind, and it is impossible to put a bunch of copper, tin, lead, and zinc together and synthesize them with one click, and then the finished products will come out.

Putting aside the boring thoughts, what Gu Guo had built now was just a furnace for smelting copper, and the construction plan for the furnace for refining tin and smelting alloys had to be postponed, and now he had not discovered the existence of tin mines nearby.

Although copper ore is usually associated with tin ore, it is impossible for Lady Luck to favor him all the time, and it is great luck to be able to find a vein within a month of crossing over.

The brain is moving, and the work on the hand is non-stop.

The foundation of the furnace was paved with mud bricks, until it was level with the ground, so Gu Guocai used terracotta bricks, and on the periphery of the furnace foundation, a layer of grass and wood ash was pressed to prevent moisture from entering the bottom of the furnace from the furnace foundation.

The most important thing is the furnace cylinder, Gu Guolei has four layers of terracotta bricks, although the performance is not as good as the refractory bricks fired with kaolin, but it can fully cope with the temperature of copper smelting that is only a little more than 1,000 degrees.

The furnace cylinder is mainly used to store the solution produced during smelting, and it is also the place where the molten copper and slag are separated.

There are mainly four layers on the inner wall, and Gu Guo only took a few glances at the contents in his previous life.

Due to its age, the illustrations of the book were rather rough, and he only remembered that the outer layer was filled with yellow mud and table salt, and the innermost layer was a mixture of charcoal ash and mud to prevent the copper from freezing.

The middle two layers, Gu Guo can only guess, he simply filled with clay mixed peat, which can strengthen the high temperature resistance of the furnace wall.

At the bottom of the furnace cylinder, it is necessary to open a copper outlet, and in the upper position, another slag outlet, because the specific importance of copper water is larger than that of slag, the relationship between the two is like water and oil when firing, one is on the next.

As for the treatment of slag, a lot of limestone was brought in when making soap, and limestone can reduce the melting point of the slag, so that the melted slag can be discharged smoothly from the furnace cylinder, so as not to become a disposable copper kiln.

In the process of masonry, Gu Guo asked Hongmei and others, who were experienced in pottery burning, to fire a pottery vessel with a cross-section like a hollow funnel, and a handle that looked like a leather peg was inserted in the upper part.

The big head of the leather peg is covered with animal skin, and the air tightness is definitely not as good as rubber, but now Gu Guo doesn't ask for too much. He pulled this blower a few times, and the air output was quite large, but the animal skin was easy to wear, and the copper that burned a few furnaces may need to be replaced.

Gu Guo and Hua and more than a dozen other people were busy, and it took five days to build a furnace more than one person high, and at this time it was past the winter solstice, and the shadow on the sundial began to move down.

The snow still hasn't stopped, and goose-feather snowflakes drift down from the sky and take a firm foothold in the newly built copper kiln.

At this temperature, Gu Guo was not sure whether it would have an impact on copper smelting, so he simply tried to make a furnace first, so that the clansmen could see what copper alchemy was.

He used sticks to calculate the number of men needed to smelt the copper, and it took at least four people to make the furnace work, except for the mining and rest of the ore.

One feeds, one blows, one fishes slag, and one connects copper water.

If ore processing is included, then it needs to be selected, crushed, charcoal-burned, and transported......

There are no twenty or thirty people who come and go, and they can't eat the smelting of the copper furnace at all.

Recalling the fierce men in the novels of his previous life, who often survived alone and rubbed iron and bronze tools by hand, Gu Guo suddenly felt that the joke was a bit big.

Nowadays, the more than 200 people of the entire tribe can barely assemble a team that is separated from food production and specializes in copper smelting before the beginning of spring. But in the spring, the tribe needs to continue to run for food.

Gu Guo selected a few clansmen who burned pottery with Hongmei, they had been burning pottery for two months, and they were definitely better than others in terms of experience, and they would be more sensitive to temperature control.

Everything was in the groping stage, and the selected clansmen listened to Gu Guo's arrangement with blank expressions.

material selection, crushing, charcoal burning, feeding, ore burning......

The clansmen just numbly followed Gu Guo's instructions, but the careful Pear Blossom wrote down all the steps.

She didn't think that Goo would spend five days in vain to make a useless stove, and that the smashed stones she had seen had brought back from a mountain in the south, and that the fine powder had a faint smell when she put it on the tip of her nose.

Remembering the story of that night, Rika felt that the priest's son was verifying the guidance of his ancestors, otherwise why would he bring these stones back so much earlier?

She kept pulling the lever of the blast stove, the whirring wind echoing in the furnace, and the blazing heat seemed to swallow her through the thick walls.

I don't know how long it took, Gu Guo, who was standing on the scaffolding, glanced into the copper kiln from the observation hole.

The high temperature of thousands of degrees steamed his eyes, but in his heart, he was extremely excited!

The ore has melted into fiery red copper at high temperatures, and slag that has not yet reached its melting point floats above the copper.

"Open the furnace!"