"...Son of God, this magnet is really a good thing!

Get more of it to absorb iron sand, and then use the iron sand to make iron tools. We can also produce some iron tools here in the main tribe, and we don’t have to transport them here from the Iron Mountain Residential Area all the time.”

In the easternmost house where Han Cheng was, the witch who came here with her daughter in her arms said this to Han Cheng with a smile, constantly praising the usefulness of magnets and making assumptions about the role of magnets in the tribe in the future.

After saying these words, Wu looked at Han Cheng with some anticipation, trying to see some emotion on Han Cheng's face such as 'Wu is so amazing, you've already figured it out before I even said it'.

However, Han Cheng, who had already found some tools and was ready to do something, was stunned after hearing Wu's words.

Han Cheng had thought about the idea of ​​magnets attracting iron sand, and then using the iron sand to make ironware.

If the magnet had appeared earlier, and the tribe had long before finding iron ore and copper ore, and using them for smelting, then if the magnet had appeared in the tribe, then the first thing that would come to my mind would certainly not be to use the magnet to make a compass, but to do as the witch said, use the magnet to attract iron sand, and then use the iron sand to make some iron tools.

But now, the tribe has copper mines and iron mines, and is able to produce real ironware through smelting.

In this case, it would be a bit redundant to use a magnet to attract iron sand and then use the iron sand to make ironware.

Or it's not worth it.

Because to make iron tools, you need a lot of iron sand.

Sometimes it looks like a huge pile of it, but in fact, not much can be made from it when used to make iron tools.

Compared with smelting iron ore and other things, it is far inferior.

Moreover, obtaining iron sand is also very troublesome, requiring people to constantly turn over the sand, which is very hard and troublesome.

In later times, Han Cheng saw people sucking iron sand in a river.

The flat riverbed was turned into piles of sand and deep pits everywhere...

Under such circumstances, he naturally had no interest in asking people to absorb iron sand and then use it to make ironware.

Wu is a wise man. Over the years, with the development of the Qingque tribe, Wu has experienced more things and is now more knowledgeable.

Before Han Cheng even opened his mouth, one could tell what was going on just from the change in his expression.

For a time, Wu was deeply shocked.

After all, the idea of ​​using magnets to attract iron sand and then make iron tools was something I came up with after racking my brains for a long time.

I was so excited about this that I ran here to find the Son of God to verify it, but the result was completely different from what I expected.

But apart from attracting iron, this magnet has no other properties other than being black!

"Son of God, does this magnet have other uses?"

Wu thought about it carefully and felt that he really couldn't think of anything, so he gave up struggling and started asking Han Cheng directly.

Having lived in the tribe for such a long time, Han Cheng already had a thorough understanding of the witch.

Seeing the witch asking this question, there is no need and it is too hypocritical to comfort her.

According to Wu's personality, even if he feels a little disappointed, he will get better after a while.

"Witch, this magnet does have other uses. For example, with it, we can use it to make tools that can identify directions.

I call this tool a compass.

After it was made, one end of this thing always points to the south, so it is called a compass.

Of the four directions, east, west, south and north, you only need to determine one to determine the rest.

With this tool, people in our tribe can rely on this compass to identify directions when walking outside without worrying about getting lost. "

Han Cheng explained to Wu.

When Wu heard Han Cheng say this, he felt relieved and nodded.

"This thing is good. It helps us keep our directions straight and makes it easier to get lost. People in our tribe will be less likely to face danger when walking outside."

Wu spoke up to answer.

Obviously, he had also remembered that a trading team from their tribe had encountered danger while going out.

"Son of God, what does a compass look like? Have you made one?"

After expressing his feelings, Wu asked Han Cheng again.

"Let me make a simple compass for you to see."

Hearing Wu's question, Han Cheng immediately perked up. After all, when it comes to things like physics, Han Cheng has one of the few confidence points.

Hearing Han Cheng say this, Wu also became excited.

Just by Han Cheng's previous words, Wu's curiosity had already been aroused.

He really wanted to see what this magical thing looked like.

It has such great uses and it keeps pointing stubbornly to the south. Just thinking about it makes it seem particularly magical.

Han Cheng also started to take action.

He had already prepared the necessary tools, so he didn't have to look around for them and could just start doing it.

Han Dashenzi walked outside and brought back a bowl, half filled with water, and placed it on the table in front of him.

Then he sat in front of the table, picked up an iron needle and placed it on a small magnet, rubbing it back and forth.

This went on for about a minute. Han Cheng stopped what he was doing and held the rubbed iron needle close to another iron needle.

Then a miracle happened. The needle was directly sucked up by Han Cheng's iron needle.

Seeing this scene, the witch standing nearby couldn't help but widen his eyes.

This is truly magical. The Son of God simply rubbed the iron needle in his hand against the magnet, and the originally ordinary iron needle now possessed the properties of the magnet and was able to attract the iron needle!

Under Wu's curious gaze, Han Cheng put aside the iron needle that had been checked and confirmed to be magnetized.

Then pick up a piece of paper on the side and fold it into a crease about two centimeters wide and five centimeters long.

After folding it, use the scissors placed on the side to cut it off.

Then, thread the magnetized iron needle along the length of the paper strip.

The two ends of the iron needle are on one side of the paper, and the middle part of the iron needle is on the other side of the paper strip.

After making adjustments, Han Cheng picked up the feather pen again, dipped it in ink, and wrote the words "North" and "South" on both ends of the paper.

After writing it, he picked it up and carefully placed it in the bowl of very calm water.

The side with the words "North" and "South" facing up.

When putting the paper with the magnetized iron needle into the ceramic bowl, Han Cheng deliberately did not put it straight, but placed it east-west.

After putting it in place, something magical happened.

The piece of paper was originally facing east-west, but after it fell into the water, it automatically began to rotate slowly.

After turning a small half circle, the magnetized needle, along with the paper strip on the needle, turned east-west and stopped there steadily, no longer moving.

But what was a little embarrassing was that the end of the paper marked south was pointing steadily to the north, and the end marked north was also pointing to the north.

Even though Han Cheng gently poked it a few times with a small wooden stick, the small piece of paper with the anvil on it was still extremely stubborn.

After it came to a complete stop, just like before, the end marked with the south was pointing steadily to the north...

The witch who was standing on the sidelines, with great reverence and full of curiosity, was ready to see something new and expand his knowledge. When he saw the scene happening before his eyes, he was a little confused for a moment.

What is going on?

Doesn’t it mean that once this thing is completed, it will always point to the south?

How come the north-south direction is wrong? And it can't be corrected?

While Wu was in such a daze, Han Dashenzi, the person who did this personally, sniffed in embarrassment.

He used two small wooden sticks to pick up the floating piece of paper and the iron needle like picking up food.

After floating on the water for a while, the note had become soft.

In this case, it is impossible to reuse it.

Han Cheng once again cut a piece of paper of similar size from the paper next to him. The words "North" and "South" were still written on both ends of one side of the paper.

After writing it, Han Cheng pulled the iron needle out of the wet paper, and then threaded it back onto the paper using the same method as before.

The only difference from before was that this time, when Han Cheng was threading the iron needle onto the paper note, he dropped the needle.

After doing all this, Han Cheng took action again and carefully placed the piece of paper flat on the water in the bowl.

This time, Han Cheng deliberately placed the end with the word "South" facing north, and then things became different.

Driven by the iron needle, the piece of paper began to rotate, and it stopped after rotating half a circle on the water surface.

Then the side with South written on it points to the South, and the side with North written on it points to the North.

Even if you use a small stick to move it, after the piece of paper stops, it will still point steadily to the north and south.

This is considered a success.

Wu was also surprised by the scene in front of him, but he also felt a little disappointed.

Because the things he saw before his eyes were very different from what he thought in his heart and the magical effects described by the Son of God. They were really too simple.

Han Cheng naturally knew what Wu was thinking.

Because when I was in the second grade of elementary school, I made it after some personal effort. Besides feeling novel, I also had the same idea.

After all, a compass sounds particularly high-end.

However, this method, which only uses a bowl of water, a small piece of paper, and an iron needle rubbed on a magnet, is indeed very different from the magical instrument in people's imagination.

"Wu, this is the most basic thing. It is used to prove whether this thing works well. If you want to make a convenient and easy-to-use compass, you still need to do a lot of things.

After all, such a compass is too crude and inconvenient to use. "

Han Cheng smiled and said to Wu...

Han Cheng learned how to make a compass using the bottom of a can in a hands-on practical class later in life.

At that time, many people, including Han Cheng, were very happy to use the bottom of a can to make a compass.

After all, he grew up in an era when materials were relatively scarce.

At that time, except for a few families, many families did not have cans or bottles.

In the practical classes at school, cans and bottles are needed.

In this case, students can openly ask their families for some money, buy a can of soda, which they crave for on ordinary days, and drink it for a while. That feeling is so wonderful!

Of course, at this time, don't even think about cans and the soda in them.

However, without the bottom of the can, Han Cheng was still not troubled. After all, many things in the tribe were slowly developing.

Now there are two things in front of Han Cheng that are very similar to the bottom of cans.

It’s just different from the aluminum or aluminum alloy material at the bottom of the can.

The two objects in front of Han Cheng, which look exactly the same in size and shape, are made of copper.

It was made based on the blueprint drawn by Han Cheng, and explained in detail to Heiwa, a master in the tribe who was proficient in making ceramics and molds. After some trial and error, it was made.

Behind the two copper objects placed in front of Han Cheng, there were many defective products that had been melted.

Han Cheng looked at the two things in front of him carefully for a while, and then put them back to back to look at them.

After seeing that they were aligned very neatly, I started to work on them.

However, before taking action, he recalled in his mind the experience of making a compass in his later life to avoid any mistakes.

After a while, Han Cheng officially started.

He started first, using a thin little drill to drill a small hole in the center of each of the two objects.

Then he used fish bladder glue to glue the two copper objects together.

Then he stuffed a small copper stick with an extremely smooth top into the center hole and fixed it with fish bladder glue.

After doing all this, Han Cheng brought over a round piece of cardboard...