Once we find the crux of the problem, the rest will be much easier.

Han Cheng relit the blacksmith furnace, took off the wooden handle behind the iron saw, put it back into the furnace and started burning it again.

Take it out after it is heated red, put it vertically with the saw edge facing upwards between two stones and clamp them tightly. Then use an iron chisel to tilt the irregular, small saw teeth to the left and right.

In fact, the best way to sharpen the teeth of a saw is not to grind it on a grindstone as before, but to first use a saw to cut a not too deep cut on a log or a stool.

Then take out the saw, turn it over with the saw blade facing up, and insert it into the sawed gap.

Then use an iron file to start sharpening each small saw tooth.

However, because the Qingque tribe now has too little iron, every piece of iron should be used to its maximum extent. It is impossible to make a special iron file for sharpening the saw, so they can only use grindstones for grinding temporarily.

"Chichi~"

"Chichi~"

The iron saw handle was held in the lame hand, and he pushed and pulled it back and forth. Fine wood chips ran out from the saw mouth as he pulled the saw, and fell to the ground sporadically, gathering into a small pile of sawdust.

The modified saw will no longer have the saw pinching problem and can be used to saw wood very smoothly.

The first carpenter was lame. He was like a child who got a new toy. He couldn't stop sawing wood.

It is said that the saw was invented by the legendary carpenter Lu Ban after he went into the mountains to chop wood and was cut by thatch.

Now that there is a time traveler, Bo, who is gradually moving towards the carpentry industry and rising in status, will not be pulled by the grass and then have the opportunity to invent the saw.

"Click"

The hard wood finally couldn't withstand the torture of the saw and was cut in half, breaking into two pieces in an instant.

The fracture is very flat and feels a little hot to the touch.

This is caused by the friction of the saw.

Lame squatted on the ground, looking at the extremely flat cut of the wood, with admiration and emotion on his face.

He had never thought of such a flat incision before.

He was also amazed and impressed by the speed of progress, which was much faster than burning with fire.

Iron tools are so useful!

This is his heartfelt feeling.

Holding the saw in one hand and the axe in the other, Lame looked at the wood on the ground and became extremely confident. With these tools, he would be able to make something more useful and beautiful!

"Brother Cheng, what is this?"

Sister Bai Xue squatted aside, pointing at the broken end of the wood and asked curiously.

The lame man who was swinging the axe also slowed down, wanting to listen to what the Son of God had to say.

There are circles inside the wood, which is something they only recently discovered.

In the past, when we cut wood, we would break the thin ones by hand and burn the thick ones with fire. The cuts were never smooth, so we had never discovered the annual rings inside the wood.

“These are tree rings.”

Han Cheng said with a smile.

"Annual rings?"

“The annual ring is the age of the tree. With each year of growth, there will be an additional annual ring in the trunk.

Sister Bai Xue tilted her head and thought for a while. After she understood what Han Cheng meant, she began to squat on the ground and count circles with great interest.

"One year, two years, ... eight years, Brother Cheng, this tree is eight years old!"

After Bai Xue counted the circles clearly, she shouted excitedly to Han Cheng.

The little child bride was so happy to discover the new thing that she ran around happily, counting the broken wooden rollers placed around.

"Brother Cheng, this tree is ten years old... this one is nine years old..."

The cheerful chirping sounds continued to ring out, surrounding Han Cheng.

Shitou, who had a dream of flying, taught those from the Yuangu tribe who had learned Mandarin a few words. Then they gathered around and watched Bo use iron tools to make tools.

Not only him, but other people from the Qingque tribe also like to gather here when they have nothing to do.

Many people were looking forward to the workers taking a break so that they could have a chance to touch the iron tools.

The teaching of the Original Bone Tribe has begun to differentiate.

Just like what Han Cheng had taught the people of the Qingque tribe before, after the adults had mastered some characters, he began to let them make their own choices. Those who wanted to learn characters could continue to learn, and those who did not like to learn the divine characters could stop learning. Learning the divine characters was no longer a hard requirement.

When it comes to the promotion and popularization of Mandarin, no discounts will be allowed.

These are all for adults. Minors who do not need to work all day can still study for nearly three hours a day as before.

Bai Xuemei did not learn with them. As Han Cheng's designated child bride, she had always been eating Han Cheng's special meal.

I don’t know if it’s because of a man’s possessiveness, but Han Cheng doesn’t want Bai Xue to have too much contact with other men, especially those who are about her age.

Living and eating with the Son of God, although Han Cheng never said anything explicitly to the people in the tribe, but imperceptibly, the people in the Qingque tribe treated Bai Xuemei differently from others.

At the beginning, Xing, Xiaomei, Xiaoli and other people of similar age who wanted to sleep with the Son of God were a little dissatisfied with this, but now, they have become accustomed to it.

For primitive people, things like love, which are still in an ignorant state, would not occupy too much of their lives, especially for those tribes that worked hard for food all day long.

Love in adolescence is more like a storm in summer, which comes quickly and goes away quickly. After some unpleasant experiences, Xing, Xiaomei and Xiaoli basically no longer think about sleeping with the Son of God.

Shi Tou squatted on the ground, touching the flat cross-section of wood that had fallen to the ground and was sawed open by Lame. His thoughts were wandering wildly, and there was some joy and impulse of sudden enlightenment in his eyes.

He has a strong interest in astronomy and calendar, and has always been confused about how old he is.

Because the calendar had not yet appeared when he was born, there is no way to know his exact age.

This is also an important reason why most tribes determine adulthood based on height.

He had been thinking about how old he was for a long time but had no idea. But now, he suddenly understood.

After a tree is sawed open, its age can be determined based on the circles inside its body. Is it possible to do the same with humans?

Would this be too painful?

Thinking of this, I suddenly regretted it.

Those who came to attack their tribe and were killed should not be burned directly. It would be better to cut them open first to see if there are some small circles on their legs...

"Shitou, what are you thinking about?"

Seeing Shitou squatting there without saying a word, Han Cheng asked.

Shi Tou was stunned for a moment, then told Han Cheng what he had just thought.

After Han Cheng heard this, his mind was full of circles and he had the urge to retreat.

Previously there were witch rabbits, and now there’s a stone that wants to cut off people’s legs to check their age... Is this really crazy?

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