The leather thing confused Tuoba tianer again.


    The Northern Wei Dynasty not only took the lead in wood.


    The key is leather, which is also very strong!


    After all, large forests and cold weather mean that the fur business is very good, and the technology involved is naturally higher.


    In fact, in terms of wood and leather, the Northern Wei Dynasty was originally much stronger than the state of Qin. It can even be said that it is not on the same day.


    But now


    For the first time, she saw someone stick leather to the wheel.


    And more importantly, it was the first time she saw someone boil this sticky thing out of the skin!


    what is it?


    How can you stick the leather to the wood?


    This makes no sense.


    In her opinion, this is tantamount to sticking two pieces of paper with saliva. It''s OK at first, but when the saliva is dry, as long as you tear it gently, the two pieces of paper will separate.


    But after Xiao Yun bonded, he cooled down for a while, pressed it with a heavy object for a while, and then tore it with force. Unexpectedly... He couldn''t tear it down at all!


    What the hell is going on?!


    Xiao Yun saw these things at every step, but she didn''t understand them at every step.


    She took a deep breath and brought back her thoughts.


    Ask him about the wood first.


    This is what she is most proud of. It is reasonable to say that she should not lose.


    So she told me again about the wood of the Northern Wei Dynasty.


    Xiao Yun had no choice but to stop his work and turn his head to look at her.


    Then he said, "do you know what the characteristics of these wood are?"


    "Ah? The characteristic... Is good, especially good!"


    "Yes, it must be good, but it''s good, but it''s not suitable for everything. I''ll ask you one thing. Do your super high wheels in the Northern Wei Dynasty often crack?"


    "This..."


    Tuoba tianer thought for a moment, then nodded and said, "crack will crack, but it doesn''t matter."


    "Are those wheels bumpy?"


    "It''s... it''s OK."


    "Are those wheels particularly heavy? If they get stuck in something, they will be in trouble?"


    "This... Does exist."


    "Also, if it rains on cloudy days, or if you walk through puddles and mud, you need to clean the wheels immediately, otherwise it will crack immediately after the water is dry?"


    "How did you know?"


    Xiao Yun said with a bitter smile: "The characteristic of millennial wood is that it grows slowly, and its annual rings are very thin and dense, resulting in high density and hard trees. The so-called density... You don''t know much. In short, when you throw a piece of wood into the water, some wood will sink and some wood will float up, right? Most millennial wood will sink underwater, so this kind of wood Wood is also called submerged wood, isn''t it? "


    "This..."


    Tuoba tianer searched his stomach and nodded for a while: "it seems that there is such a saying."


    Xiao Yun said with a smile, "this kind of wood is characterized by hardness! If you stroke or simply bump, it will not immediately deform seriously, and this kind of wood has high grease, so it also has some advantages in insect prevention and water splash resistance. But that''s all."


    "So good wood, how can you have such advantages in your mouth?"


    Xiao Yun said with a smile: "Don''t worry, among these woods, they have different characteristics according to their types. Some woods are particularly insect resistant, some are particularly difficult to burn, and some are particularly difficult to deform and crack, but... It''s difficult to have a kind of wood that accounts for all the advantages. For example, those that prevent moths may be particularly easy to deform, and some The oil is very high and hard, but the natural lines are not good. If it is a little wet, it will crack along the lines. Because the lines are not neat, there are all kinds of cracks. "


    He took a sip of warm water and smashed his mouth, Continue: "Take Qinan of Northern Wei Dynasty as an example. It''s really a good thing. It has a natural fragrance. Needless to say, it can prevent all kinds of insects. It''s also characterized by careful grinding. There will be a layer of soft luster on the surface, which is particularly beautiful. More importantly, it won''t deform easily. A piece of wood can not deform for thousands of years as long as it is carefully taken care of! Squeeze It will not be reduced. Therefore, considering all its advantages, what it is most suitable to do is furniture. Even in the state of Qin, who can have a set of furniture made by Qi Nan of the Northern Wei Dynasty is at the top of wealth. Among them, high-quality products are more valuable gold, right? "


    Tuoba tianer looked proud and said, "hum, you have some knowledge!"


    Xiao Yun said with a bitter smile: "but Beiwei Qinan has a fatal disadvantage, which also leads to... It is too difficult to serve. Few people use it as a table. Even if someone uses it, they don''t understand. They just remember its precious and show it at will."


    "What are the disadvantages?"


    "It''s too afraid of water!"


    Xiao Yun sighed, say: "Qi Nan in the Northern Wei Dynasty was first called" falling water green "in the mouth of carpenters. Qi Nan was originally yellowish brown, with a little red light. It was very bright, but if it splashed water, it didn''t need much, just a drop of water, then there would be black spots where the drop of water fell. That is to wipe it off immediately, but also to reduce the depth of the black spots. After all, there are still black spots. You use tea Drink water from the cup. If you don''t put something on it, when you pick up the cup, a circle of black lines will appear on the table. If you accidentally spill the tea bowl, it will stimulate. The place where the water flows is dark! Want to bring it back? It''s almost impossible unless you grind off a layer. "


    "It... Seems so."


    "So even if it''s as precious as Qi Nan in the Northern Wei Dynasty, it''s only suitable for making wardrobe, dressing table, especially some jewelry boxes and other small and exquisite things that can be maintained from time to time. If it''s placed in a damp place, it can''t see anything at that time, but as soon as it dries, it''s not just black and directly cracked! I''m right about it from the beginning to the end ？”


    "That''s true."


    "What if you used your Qinan from the Northern Wei Dynasty to build a ship?"


    "Ah? Who would be so stupid to use it to build a ship? Wouldn''t it be like sinking a ship when it''s underwater?"


    Xiao Yun said, "this is just an extreme example, but from this example, you should also know what is suitable? Wood, unlike other things, should be suitable for everything. Some wood is good, but it is really not suitable for making wheels."


    "What kind of wood is suitable for making wheels? Your wheels... Obviously you have a big piece of wood that can be made into a circle. Why do you have to get several pieces here? You have to use that complex method to get them together. Isn''t it plain and laborious?"


    Xiao Yun laughed and said, "you see the wheel too simply. Even if I can''t simplify it any more, there must be four different materials on the wheel. The wood on the edge can''t reach the ball in my heart anyway, so I used some special methods of tenon to make it a little bit more."


    Tuoba Tian''er''s eyes turned, leaned over and said, "then talk about it carefully."


    "This is because... Well, why should I say it?"


    "Eh? Don''t be so stingy."


    "Please, we are enemies. You are a spy in the Northern Wei Dynasty."


    "Gee, don''t be so ugly. Besides, we can''t get out now. It''s unknown whether we can go out in this life. It''s always okay to talk about it."


    Xiao Yun couldn''t help laughing bitterly.


    Xinzhi knows that this is Tuoba tianer''s core technology.


    But... It''s really boring at this time.


    And he also wanted to suppress Tuoba tianer''s spirit and let her not always think how great the Northern Wei Dynasty was. Her thought is deeply rooted. After all, this is the education she received from childhood.


    Xiao Yun coughed twice.


    Carefully said: "first of all..."


    He pointed to a thick looking piece of wood in the middle of the wheel, with a hole in the middle.


    "This is called the hub, and you can also call it the hub. No matter what wheel it is, the hub is in the middle, and the center is penetrated by the central shaft. When the shaft is stable and the hub moves, the wheel will turn and the carriage can move forward."


    "Is there a separate name?"


    "Of course! Each part has a separate name... Cough, you don''t even know this?"


    Tuoba tianer blushed and immediately said, "naturally, I know, but... I just didn''t think of it for a moment."