The second batch of copper ore was brought back by Team B.

The total weight of the first batch of copper ore shipped back is more than 7,000 catties, and the second batch of copper ore is close to 8,000 catties.

The copper ore that is easy to find and excavate on the surface can only be mined downwards after being mined, and the efficiency of mining copper ore will only slowly decline, which is also a helpless thing, and it is very lucky to be able to find such a suitable copper mine.

Half of the smelting area adjacent to the river has been cleared, the other half is being cleared, and two batches of ore from the copper mine have been transported to the side of the smelting area for stacking, and a batch of adobe bricks has been transported to the side of the smelting area to be used for the construction of earthen blast furnaces and brick kilns.

On a new day, Biao Heyuan took fifty adult male clansmen to form a hunting team to go out hunting, Shen took Team C to the small river to fish, and Su Yan took more than fifty clansmen to the smelting area to stay in the tribe.

"Jian, you take half of the people to continue pulling weeds and cutting trees." After coming to the smelting area, Su Yan gave a task.

"No." Jian took the order, and led more than twenty clansmen to turn around and continue to clean up the uncleared area on the west side of the smelting area.

After Jian left with half of the people, there were less than thirty people left in the cleared area of the smelting area, Su Yan continued to give orders, and the remaining people were divided into four groups of seven people on average, and each group was responsible for building a building, three of which built a brick kiln, and the remaining group built an earthen blast furnace.

On the west side of the smelting area, Su Yan carved out four small areas with tree branches, three of which were placed in parallel, each about 10 square meters, and each of these three areas would build a brick kiln.

Compared with the earth blast furnace, the structure of the brick kiln is slightly simpler, among which the clansmen participated in the construction of the first brick kiln of the Dragon Tribe, and have certain construction experience, Su Yan only divided a little effort to direct these three groups of people to build the brick kiln, and the focus was still on the construction of the earth blast furnace.

The earthen blast furnace that has been sketched by Su Yan is a round platform (column), about two meters high, about one meter in diameter at the bottom, and about 0.6 meters in diameter at the top.

Now Su Yan only needs to command the clansmen to build it according to the drawings he sketched, and as for improving the earthen blast furnace, he has to wait for this earthen blast furnace to smelt a few furnaces of copper water before he can improve it.

Bricks are piled up, brick kilns and earthen blast furnaces are being built at a rapid pace.

"Don't put adobe bricks here, it's empty here."

"Put a few more adobe bricks there and thicken them."

"Yes, that's it, there's no need to leave any more gaps, pile up adobe bricks on top."

The clansmen conscientiously completed Su Yan's instructions one by one.

The structure of the brick kiln is simpler than that of the earthen blast furnace, and the construction is faster, and the three brick kilns are almost completed in the afternoon, just waiting to plug all the cracks of the brick kiln with clay.

Watching the clansmen use clay to block the cracks in the brick kiln, Su Yan suddenly thought of something related to making metal tools after smelting copper.

How do you make tools out of copper?

The first idea that popped into Su Yan's mind was to use the method of striking iron to make copper into tools.

Iron striking is to exercise red-hot steel and make it into the utensils you want.

Blacksmith, a very familiar profession that has been far away from modern people, in ancient times, every piece of steel weapons and farm tools was hammered by a blacksmith with a hammer.

Forging or iron-striking is a technical job, and it is very difficult for a newcomer who does not understand iron-making technology at all to create the simplest farm tool with a hammer, and it takes a long time to explore, Su Yan is such a newcomer.

Forging is a technical work, but there is a way that the metalworking process is much simpler than forging, there is hardly too much technology to speak of, and it is also the first metalworking process mastered by human beings - casting.

Casting is the liquid metal cast into the casting cavity that is suitable for the shape of the part, and after it is cooled and solidified, the method of obtaining parts or blanks, copper and iron are suitable for casting, the Shang Dynasty period weighs 875 kilograms of Simu Wu Fangding, the Warring States Period Zeng Hou Yizun plate, the Western Han Dynasty translucent mirror, are the representative products of ancient casting.

Compared with the forging process, which is to hammer back and forth with a hammer, the casting process only requires pouring hot copper or iron into a pre-made casting mold, and the metal juice can be cooled to obtain the desired metal tool.

The material used to make the mold is also very simple, just use the clay that can be found everywhere on the river bank.

If you want a knife, you can cut out the shape of a knife on this cuboid clay, pour the hot metal juice into it and cool it to get a knife blank, polish the blank carefully, and a large knife is officially baked.

Swap the knife for a sword, spearhead, dagger, axe, shovel, etc.

The Dragon Tribe's first metal tool is about to be born, and Su Yan decides to create a tool that makes the most sense to the Dragon Tribe—a ruler.

The unification of weights and measures is one of the great achievements made by Qin Shi Huang, the just ended Warring States period of the original countries and regions have used their own weights and measures, which is very unfavorable to the development of industry and commerce, when the weights and measures are unified, the economic exchanges in various regions become smooth.

Su Yan brought the text into the dragon tribe, but the description of length, weight, and volume is still relatively primitive, usually if you want to express a certain length, you will directly use the length of a rope or wooden stick to express it, if you want to express the distance between two regions, you can use how long you have walked to express it, and the weight is also compared with another object.

Without accurate weights and measures, the impact on the previous dragon tribe was not great, and Su Yan was not in a hurry to take out the accurate length, weight, and volume units, but soon the dragon tribe will use these.

For example, in the manufacture of hydraulic machinery, some parts of hydraulic machinery need the same size, and it is very troublesome to compare back and forth.

So now it's also time to bring accurate weights and measures to the dragon tribe, and the first step is length.

Su Yan asked the people to find clay to make a casting mold, and the space vacated in the casting mold was about a rectangle about sixty centimeters long, two centimeters wide, and one centimeter thick.

The exact length of the previous life Su Yan can't express it accurately, he can only feel a rough idea, but that's not important anymore, now it's Su Yan to determine the length, and the length determined by Su Yan is the standard.