"Accurate to centigrade!" Li Yun took a deep breath and began to calm down and start measuring.


    For the accuracy required by Mohist ruler, he has a great feeling of confidant. The more skillful he is, the more demanding he is for accuracy.


    This is not a simple statement, especially for difficult projects such as the construction of arch bridges, which have high requirements for the accuracy of measurement, and often a small mistake will cause disastrous losses. Even if the craftsman has accurately measured it, he still measures it in person, which is reassuring and ensures the quality of the arch bridge.


    One foot equals ten feet, one foot equals ten inches, and one inch equals ten. Li Yun repeatedly determined that he did not dare to be careless, and tried to be extremely accurate.


    "One point equals ten li!" however, when Li Yun was accurate to Li Li, he was stunned, because the Tang Dynasty was divided into large ruler and small ruler. Li Yun''s standard was large ruler. Rao''s one point of such a large ruler was only equivalent to about three to four millimeters in later generations. Such a short distance could not be accurate to 10 Li at all.


    "Sure enough, it''s not that simple!" Li Yun sighed in his heart. He knew that the problem of Mohism was not so simple. It was impossible to be accurate to 10%. Even if it was forcibly divided, I''m afraid it would destroy the ruler and can''t see the scale clearly.


    "Zi Mozi said: middle, the same length. Since there is no way to be accurate to every centimeter, but it can be accurate to the fifth centimeter." Li Yunling''s machine moved, as long as it is accurate to the fifth centimeter, if you need more accurate scale, you can visually measure the closest length.


    When he personally engraved the fifth percentile mark in the middle of each inch, he looked at the precise scales, and his heart was suddenly filled with pride. This was the ruler with the highest accuracy he had ever used.


    This ruler can be said to be priceless for the children of Mohism. With such an accurate ruler, he can accurately measure all things in the world. There is a feeling in his heart that everything in the world is clear in his heart and lies between sizes.


    "The next is the most important step, which is to let the wooden ruler be controlled by one hand." Li Yun looked at the wooden ruler much higher than him and couldn''t help falling into meditation. Two of the three requirements have been completed, and the rest is the most difficult part. How to make a Zhang long wooden ruler controlled by one hand, Li Yun looked at the Zhang long wooden ruler in front of him and fell into deep distress.


    Originally, when he was holding a three foot long wooden ruler, he didn''t think the course was very difficult. However, when a ten foot long wooden ruler was placed in front of him, it made him solemn.


    To tell the truth, a ten foot long wooden ruler is very common in practical use. When measuring some large objects, he needs such a long wooden ruler. Originally, he didn''t feel anything. However, when he combined the requirements of Mohist school, he found how convenient it would be if he really made the ruler that Mohist School said.


    "How did the Mo family do it!" however, after a long time, Li Yun still had no clue. No matter how hard he thought, he couldn''t think of how to turn a ruler one foot long into a palm.


    "Young master, in my opinion, it must be the Mohist school who is talking nonsense. He himself admitted in public that distance is immutable. How can a ruler of one foot long become a slap in the face?" the old servant comforted.


    Li Yun shook his head dejectedly and said, "although mojiazi said that the distance is immutable, we have changed the current situation and changed the distance. Those who detour can build bridges and roads, and those who go a long way can speed up cars and horses to drive a longer road in a shorter time. So is the intention of mojiazi!"


    The old servant couldn''t help but acquiesce, and didn''t know how to comfort Li Yun. After all, since Mohist Zi had given his apprentice a question, he must have had an abdominal manuscript in his heart.


    However, after a long time, Li Yun still had no clue. According to his knowledge, there was no way to do it.


    "It seems that I''m still too conceited. I thought I could compete with Mozi. Now it seems that even Mozi''s disciples may not be able to win." Li Yunyue thought more and more angry. He couldn''t help getting angry and angrily threw the made wooden ruler on the ground.


    The wooden ruler is a foot long. It is made of thin and long wood. It was heavily thrown to the ground and directly broke into several pieces.


    The old servant said sadly, "this is a wooden ruler made by the young master with great efforts!"


    Li Yun spent so much effort on the wooden ruler. He looked at it and saw that the wooden ruler was completely destroyed. He couldn''t help but bend over and pick up the broken wooden ruler on the ground one by one.


    There were a lot of broken wooden rulers. When the old servant picked up a few, his hands couldn''t take them down. Finally, he had to stack the wooden rulers in his hands and continue to pick up the remaining broken wooden rulers.


    However, the old servant didn''t see it. When Li Yun''s decadent eyes inadvertently saw the wooden ruler stacked together, he suddenly rose up and his eyes were suddenly bright.


    "Hahaha, I understand. I finally solved the problem of Mohism." Li Yun suddenly laughed like crazy.


    "Young master! What''s the matter?" the old servant quickly got up and looked at the crazy young master in horror.


    However, Li Yun ignored the old servant at all. Instead, he directly picked up a long broken wooden ruler and snapped it again.


    In the worried eyes of the old servant, Li Yun stacked pieces of broken wooden ruler in his hand. He saw that the one foot long wooden ruler was only as wide as the palm.


    "The young master means to cut a ten foot long wooden ruler into small sections?" the old servant suddenly realized Li Yun''s intention.


    Li Yun nodded proudly and said, "yes, although the ruler is long, it is about five centimeters thick. If we cut a Zhang long wooden ruler into half a foot long, it will only be an inch wide. Only in this way can we make a Zhang long ruler between our fingers and palms."


    "But in this way, it''s more troublesome to use such wooden rulers one by one. I''m afraid they are no longer accurate." the old servant shook his head. When measuring an object, it is very troublesome to spread it with a wooden ruler section by section. If you accidentally move a wooden ruler, the length is no longer accurate.


    Li Yun laughed and said, "what''s the difficulty? We just need to build a ''bridge'' between the two wooden blocks, connect the two halves of the ruler with rivets, and connect it like a chain."


    Li Yun said on his mouth, picked up two small pieces of wooden ruler in his hand, pinched the tail with his fingers, and flexibly moved the two halves of wooden ruler back and forth.


    The old servant immediately brightened his eyes and exclaimed, "young master is really smart. He has solved the problem of Mohist school so easily."


    Li Yun couldn''t help showing a trace of pride, but then sighed: "craftsmen in the world don''t know how many people are used to using three foot wooden ruler. Only Mozi is dissatisfied with three foot wooden ruler. We all think Mozi is picky. Now we know that as long as we have a heart, everything in the world is not difficult.


    "Once such a wooden ruler comes out, it must be the gospel of craftsmen all over the world. Please give it a name," the old servant said with a pleased face.


    "Since these wooden rulers can fold each other, how about calling them folding rulers?" Li Yun said in his heart.