Then Su You connected each inch marked point of the bottom right-angled side with the other 45-degree angle of the right-angled triangle. Together with the hypotenuse, nine dividing diagonal lines were obtained.

Finding a new ruler without markings, Su You prepared to compare the points obtained by drawing and mark the precise position of each inch on the ruler.

An old craftsman, probably the foreman, quickly said: "Xiao Lang, I will do this."

Su You smiled slightly: "Then I'll have to thank you."

The old craftsman was skilled in his craftsmanship, and soon Su You got a ruler marked to precise dimensions.

Su You used the ruler to move upward along the right-angled edge. When the distance between the side and the outermost hypotenuse of the picture was exactly one inch, the eleven diagonal lines divided the inch on the ruler into ten equal parts.

Pull the horizontal line and you will get an accurate ten points on the graph.

The craftsmen began to respect Su You's skills. The experts would know if they were there as soon as they stretched out their hands, especially the foreman, who kept shouting "Wonderful! Wonderful!"

After saying that, he took over and marked each minute on the ruler with a sharp tool. Then he continued to imitate Su You and moved the ruler up. He frowned and said: "Little sir, I can't continue. One centimeter is divided into ten points."

, Theoretically it is possible, but the needle marks are right next to the needle marks and cannot be marked.”

Su You took out another piece of paper and drew the same picture, but this time the length of the right angle was only nine inches.

The foreman pointed to the new right triangle: "Then this scale is nine-tenths of an inch. Do you want to get nine-tenths of an inch?"

Su You smiled and said: "Exactly, by using nine versus ten, the centimeters can be displayed above the nine-point scale."

The old craftsman felt like his scalp was exploding: "This... what kind of ingenuity is this? How can it be done?"

Su You first figured out the nine-point scale, and said to the craftsmen: "Young man can only theory, but it's a mess when you do it, and you still have to work hard for me."

The old craftsman did his part: "It's necessary. How dare you do such menial work, young man? Come on, old man!"

Su You smiled and said, "Then I'll trouble my husband."

Next, things became much easier. Su You drew a drawing of a vernier caliper and explained the key points clearly to the old craftsman. Soon, a strange and exquisite Qinggang wood ruler appeared in Su You's hand.

Su You was very convinced when he looked at the caliper, which had a discernible light: "My father-in-law's skills are at their peak."

The old craftsman waved his hands repeatedly: "My family has been a carver for three generations, and the fine wood work is a craft inherited from my family. In my lifetime, I have finally become a big carver, so I am in charge of the engraving of this bookshop for my boss."

"That's true, but I don't dare to boast that it's perfect, and I won't be able to praise the little gentleman. Right now, this can only be a makeshift model. I'll make a durable one for the little gentleman someday."

Su You smiled and said: "You deserve it, you deserve it. Pure manual work and engineering work are two different things."

After that, he introduced to the craftsmen: "Look, the one in the middle is the main ruler, and the one at the bottom that can slide is the auxiliary ruler. The scales on the auxiliary ruler can move on the main ruler. The marks on it are what I call

for the cursor."

"In front of the vernier are two clips, which are used to measure the width of the object, so I call this ruler a vernier caliper."

The old man nodded repeatedly: "This name is very appropriate."

Su You took a wooden block and said: "The key to this caliper is that when the auxiliary ruler reaches the end of the main ruler, the starting scales of the two feet will be aligned, and at the same time, the inner surfaces of the two calipers of the clamp will be tightly connected."

After speaking, he looked at the ruler and shook his head: "My father's craftsmanship is really exquisite."

The old man's heart was like a cat scratching his head: "Little sir, stop praising me. I have no place to praise you anymore. Why don't you show us how to measure to the centimeter level?"

Su You stuck the wooden block and said: "Look, I call the starting point of the scale of the main and auxiliary rulers the zero point. From the position of the main ruler shown by the zero point of the auxiliary ruler, we can see that the width of the wooden block is more than one inch and five minutes."

The craftsmen all nodded, this is simple.

Su You said: "How much more is it? Let's look at the auxiliary ruler. Look at the two ends of the auxiliary ruler and the positions corresponding to the scales of the main ruler. Are they gradually approaching a point? The closer they are to that point, the larger the auxiliary ruler and the auxiliary ruler.

The scales on the ruler tend to overlap more?"

A craftsman with sharp eyes said: "Yes, yes, the sixth mark on the auxiliary ruler almost coincides with the first mark on the main ruler."

Su You smiled and said: "This uncle is right, the scale indicates centimeters, and the width of this piece of wood is one inch, five minutes and six centimeters!"

There was a sudden surge of people in the Todoroki workshop. This was the first time that everyone had seen a ruler that could be accurate to the centimeter level!

Amid the cheers of the crowd, the old craftsman's face was full of doubts: "Little sir, what does this mean?"

Su You said: "This involves arithmetic. I call this problem chasing differences. Can everyone do arithmetic, addition and subtraction?"

Everyone nodded like a fool, they know this.

Su You said: "It will be easier if you have a city. Come and see the pictures."

After that, Su You began to explain the principle of the vernier caliper. After some explanation, Su You concluded: "Look, let's assume that the width of the caliper is one inch, three minutes and nine centimeters. Calculate it bit by bit. At the ninth point on the auxiliary ruler,

At the position of this point, the distance difference between it and the scale of the main ruler is exactly zero, and the difference has been caught up."

"Using this characteristic, we can enlarge the unit of centimeters to the scale of the secondary ruler and obtain accurate centimeters."

A group of craftsmen couldn't help but admire them. It was one thing to be able to make something, but it was another thing to be able to explain the truth thoroughly.

This shows that the young gentleman is not blind. Everyone understands the truth once he hears it. But if you have to rely on your own imagination, you will definitely not be able to get such an exquisite solution even if you break your head.

Wait, the little gentleman seems to be only five years old? Then at this age, wouldn’t it be like living in a dog’s belly?

The old foreman bowed deeply to Su You and said: "With this ruler, our Meishan Bookstore, hahaha, from today onwards, we will surpass Jianyang, Hangzhou. Sir, you should be honored by the old man."

Su You quickly waved his hand and said: "Don't dare, don't dare, you are an elder, but there is absolutely nothing you can do."

The two of them were in the guest room when they heard a slight cough behind them. When they turned their heads, it was Cheng Wenying who had arrived.

Cheng Wenying saw Su You and Ba Niang mixed in a group of craftsmen. He frowned slightly at first, but said nothing. He only said to the old foreman: "Old Yu, you can hear the noise in the workshop in the inner courtyard. Do you want to discard the rules?"

The old foreman quickly handed over his hand: "Congratulations to my boss, I'm so happy, the little gentleman has invented something amazing!"

Cheng Wenying asked: "What kind of thing makes you so surprised?"

The old foreman handed the ruler to Cheng Wenying: "Look, boss, this is a magical ruler that can measure to centimeters!"

Cheng Wenying was shocked: "How is it possible?"

After the old foreman showed the ruler again, Cheng Wenying also felt that the design principle of this ruler was extremely simple, but the cleverness of his thinking was so incredible that he couldn't help but look at Su You up and down.

Su You held up his hand to Cheng Wenying and said, "Brother-in-law, actually this ruler can be improved a lot..."

Cheng Wenying grabbed Su You's wrist and held the vernier caliper in one hand: "My nephew and I will go into the inner courtyard to have a detailed discussion."

Even Banniang didn't care. Banniang pursed her lips and smiled, and followed obediently from behind.

Entering the inner courtyard, Su You said to Cheng Wenying: "Uncle-in-law, this caliper..."

Cheng Wenying sighed and said: "My dear nephew, my first priority is to advance to the rank of scholar, and secondly to make policies. As for the other miscellaneous subjects, for others they are the level of promotion, but for you... My dear nephew is very smart, so he should use poetry and calligraphy as his guide.

Seriously, you must not explicitly calculate it as the way to enter the body, this is a self-mistake."

Su You's impression of Cheng Wenying became more and more favorable. He stood up and saluted, "My nephew understands that these are just ordinary miscellaneous studies that are not considered relevant. When he is enlightened, he will make a career in Confucian classics."

Cheng Wenying breathed a sigh of relief: "That's good, that's good... I just heard you say that this thing is of great use?"

Su You told Cheng Wenying what Banniang was thinking, and Cheng Wenying sighed: "Banniang, the whole family should not be so estranged. If there is anything, you should tell Weng's son-in-law, or you can tell me."

After hearing this, Ba Niang couldn't help but her eyes turned red, and she quickly lowered her head to apologize.
Chapter completed!