The reason why Zhang Shou has always been a lot, and the students of Jiuzhangtang and Banshan Hall have a deep understanding. Sometimes you listen to those difficult content yourself, and when you are already confused, people will suddenly throw out a bunch of whys, which will catch you off guard and be confused for a long time. And the most annoying thing is that after why, Zhang Shou is mostly not responsible for answering, but letting you go back and think about it yourself!

Sometimes, after they thought for several days but still couldn't understand the essentials, Zhang Shouhui answered with compassion in class, but more often, he just continued to induce them to continue to think and ponder. In a sentence that Zhang Shou often said, the magic and mystery of the world do not depend on others to answer, but on asking why when there is nothing to do, and then to think about it and comprehend it.

However, on an occasion like today, Zhang Shou will not still play people so badly, right?

Lu Sanlang was very uncertain in his heart, and he could only hope that the third prince and the fourth prince brothers could help a little bit, and don't let those people continue to think about themselves. Sure enough, the third prince, as a diligent and studious prince, was really carefully trying to figure out why at this time, but the fourth prince, a bear child, asked directly without any scruples.

"Do you know why the teacher is here?"

Seeing that the bottom was completely cold, and the faces of many scholars were either stunned or confused, Yue Shanchang planned to come up by himself and ask for advice, but he didn't expect the fourth prince to snatch it again, so he sat down in a good time. You must know that he, the head of Zhaoming Academy, has a lot of miscellaneous studies, but although he has noticed many phenomena, he is still unable to solve the truth.

If Zhang Shou really said that there are many, many teachers, then people dare to open directly with such a topic in front of so many astronomical talents and people from all over the world at this moment, then they will definitely be able to give a reasonable answer. Otherwise, isn't that a joke?

Zhang Shou did not immediately answer the question of the fourth prince, but continued to ask: "Why do gold, iron and stone sink to the bottom when they enter the water, why can some wood float on the surface of the water, but some wood sinks to the bottom?" Why does the same liquid, the oil float on the surface of the water, but the mercury sinks to the bottom? ”

After the three whys, seeing that there was already a commotion among the people below, as if someone was still saying that this was all common sense in the world, and there was something to explore, he said calmly: "Don't think that these phenomena can be seen everywhere, but they have always been commonplace, then it is not surprising. In fact, all the truths of the world are hidden in what we see in our daily lives. ”

"You know, in the past, when I solved the plaque of Jiuzhangtang that contained Emperor Taizu's handscroll in public, the principle was similar to the truth in it."

"The rise and fall of objects on the surface of water, or in other liquids, depends on the density of those objects and liquids, and liquids such as pure water, salt water, and oil also have their own densities. So, a dense object will sink to the bottom in a liquid with a low density, and an object or liquid with a low density will float on the surface in a liquid with a high density. ”

"And if the density of the object and the liquid is almost the same, then it is likely to be completely submerged in the water, but instead of sinking to the bottom, it is suspended in the middle of the water. Of course, if there are still people who think that this is a demon law, then after going back, they can verify it. As long as the salt is added little by little and dissolved, it should be possible to verify not only the suspension, but also the floating. ”

After dropping a bombshell again, Zhang Shou saw that many people were eager to try it, and it was obvious that he really planned to verify this extremely simple experiment after he returned, so he continued with a smile: "Now, let's continue to talk about density. What is density, the mass of an object per unit volume, that is density. And is there such a thing as density that works in real life? ”

The answer is simple, of course it works. Not to mention that when coinage, often because the proportion of copper is too low, the copper money is too light, so the people are difficult to trust, but if the proportion of copper is too heavy, the burden of the court is large, and the workload of the miners is greater, and if the density is mastered, then not only copper coins can be minted, but also silver coins, and even gold coins. ”

"Of course, money is the most important weapon of the country, today we will not talk about this, but another thing, that is, measuring tools."

Zhang Shou said as he glanced at the three princes who were listening extremely attentively next to him, and then continued unhurriedly.

"The ancestors once invented measuring tools for weighing rice flour and corn, sorghum and other food crops, such as Hu, bucket, liter, he, spoon and the like, so far, these measuring tools are still the evidence for the imperial court to collect taxes, and even for landlords to collect rent, and civilians to buy grain. And these measuring tools, do they weigh the rice noodles? No, these gauges actually measure the volume of various grains. ”

"In other words, weighing grain with a measuring tool is completely different from weighing pork and mutton with scales in the market."

"His Royal Highness the Crown Prince once asked a question about agriculture in the examination question of the East Palace attendants, I think this news should have been spread now, at this moment, no one should ask what is Hu, Dou, Sheng, He, Spoon, and how do these measuring tools weigh grain?"

He paused, and saw that some people would smile, but there were also some people who were hiding the dazedness on their faces, and he knew that among these people who were dedicated to reading sage books, I was afraid that there were many people who had never seen the things of the ascension, and he couldn't help but smile slightly.

"The measuring tool was originally an official system, but in the hands of some black-hearted guys, they often came up with their own set of things, for example, big and small buckets. Big buckets are collected, and small buckets are sold to make a profit. Today, I won't talk about this, but just another technique, which is the so-called, drenching and kicking. I would like to ask, does anyone know what these four words mean? ”

The third prince frowned suddenly, but he couldn't think of it at all, and he wasn't even sure which four words these four words were. Seeing the buzz below, although most people tried their best to keep their faces calm, the fluttering eyes showed that some people, like him, heard these four words for the first time, and some people may know the cattiness.

Thinking of this, he didn't plan to just be an observer today, and he immediately asked, "Is it true that no one knows what the teacher asked?" ”

Seeing that there was still no response, he simply laughed self-deprecatingly: "It seems that you would rather let Lone be a lonely person?" ”

As soon as the words fell, the third prince saw a young man Huo Ran get up and said loudly: "Returning to His Royal Highness the Prince, the so-called drenching and kicking is a kind of malpractice when the tax collectors collect grain!" When the people carried the grain to hand it in, the government did not use a sheng bucket to weigh it, but to weigh it with a hu. The so-called Hu is a measuring tool that can hold five buckets of grain! ”

The fourth prince found that the person actually recognized it, and he once questioned Fang Qing, who was tired of his third brother's solution in the Jiuzhang Hall of the Guozijian, and was later left in Zhang Yuan by Zhang Shou, he didn't care that this was in front of the public, so he hurriedly attached it to the third prince's ear and muttered and reminded him. And the third prince laughed dumbly. Do you need to explain? It's not like I don't know!

And Fang Qing stood up in anger for a moment to uncover the matter, although he had already sensed that Song Juren was desperately pulling the corners of his clothes, he didn't pay attention to it. After all, I think that when he was not famous, his family was exploited by this, and later it was better to have fame and less food.

"Reasoning, a Hu is five buckets of grain, should be loaded to the mouth of the mouth of the level prevails, but in order to be able to gain more losses, the officials often require the people to continue to load grain after leveling, until the grain is piled up in the mouth of the mouth to emerge sharp. It's called drenching. ”

"But if it's just like this, even if it's a maladministration, it can be regarded as storing grain for the country, but these officials often have a more powerful trick, that is, kicking Hu. You must know that Hu is flat on the ground, once the tip is drenched, a kick up, will naturally spill a lot of food, which can be blatantly regarded as loss, and fill your own pocket! ”

"There are those who have darker hearts, in order to collect more food, kick Hu, let the people drench again, and wait for the warehouse to be re-weighed...... according to Pinghu"

As soon as Fang Qing said this, the face of the third prince finally gradually changed. He never imagined that there would be so many famous people who collected taxes and grains. Seeing Fang Qing sit down like this, he couldn't help but ask Zhang Shou, "What the teacher just said, is this the case?" ”

"Yes, but not exactly, what I was trying to say, there's another thing hidden in the drenched kick."

Zhang Shou smiled casually, and then clapped his hands gently, and after a while, he saw Ah Liu, holding a Hu in one hand and two rice bags in the other, and walked over easily, and then put the things next to Zhang Shou. It's just that the muffled sound of the bang sounded, and everyone below realized that these two things were extremely heavy.

"In the two bags, they are all measured with Guan Hu, five buckets, that is, half a stone of millet. Now, Ah Liu, you put it in this official hall again and show it to everyone. ”

Ah Liu has always been a person who does what Zhang Shou says, and immediately untied the rope of the bag according to his words, and after lifting it easily with one hand, he controlled the mouth of the bag to fall into the big husk.

Although the people below couldn't see the specific situation, they could still hear the movement of the grain pouring down. And the fourth prince, who was watching intently next to him, couldn't help but shout: "Sixth brother, be careful, it's almost full, don't spill it!" ”

Ah Liu looked at the pouring grain, and glanced at the four princes who were shouting with contempt, and wanted to say that when he was in Rongshui Village in the past, he didn't rely on Lao Liutou's unreliable guy when collecting land rent, but all relied on him. Just this kind of trick of pouring grain into the hu, he is an old trick, and he still needs to be reminded?

Sure enough, when he was about to reach Hukou, he directly and quietly closed the mouth of the bag, and the speed of the millet falling was much slower for a while, and he skillfully adjusted the direction of his wrist and the mouth of the bag, and poured all the grains in the bag in a short time, and then wiped it flat with his hand. At this time, the third prince and the fourth prince on the side saw that Guzi was just at the same level as Hukou.

The fourth prince is not more reserved than the third prince, and when he saw this, he immediately shouted: "The sixth brother is a good means, and it is flat!" ”

Seeing the testimony of the brothers, Zhang Shou smiled and said: "This is the real Yihu, that is, half a stone of grain, now, I won't drench the tip, Ah Liu, you kick it." Hold on to me, don't kick down, don't spill grains, and don't kick this official Hu badly! ”

As soon as these words came out, Lu Sanlang, who was going to pick up the gaps on the side, but didn't find a chance at all, suddenly sweated profusely, and the fourth prince couldn't help but think of the sin that his ass had suffered, and for a while he only felt that Guan Hu was himself, and hurriedly flashed directly behind his third brother. As for the other speakers, and those who came to listen to the lecture below, they were stunned and stunned.

They have grown up and listened to countless lectures, but how can they have experienced such a unique lecture?

Although countless eyes fell on him, Ah Liu was still very calm, he didn't do too much preparation like the tax collectors in the government, and he didn't even take a step back, but casually raised his foot and kicked on the official hu. The fourth prince even found that the official Hu didn't even move, and couldn't help but widen his eyes and said, "Sixth brother, your feet are too light, aren't you......" Could it be because I didn't eat enough today?

Before he could finish his words, he was directly interrupted by the third prince: "Fourth brother, don't shout if you don't understand!" With his foot, not a single grain of grain was sprinkled that was just level with Hukou, and the most important thing is that you look at the millet in this Guanhu now! The fourth prince was slightly stunned, and when he looked inside, his eyes widened: "Really, it seems to be less all of a sudden!" ”

Although among the people who came to listen to the lecture with an invitation card today, they are indeed all scholars, so even the trick of drenching and kicking Hu, few people know about it-otherwise, the thing that is in the limelight in front of His Royal Highness the Crown Prince may not be Fang Qing's turn, even if some people will be afraid that they will attract hatred after the news spreads, but there has never been a shortage of gamblers who dare to fight in this world, but for this situation, no one has predicted it.

At this moment, someone immediately shouted: "Isn't it the case that you use boxes and things like that?" It's obviously full, but as long as you knock and pat it, you can still load it again! ”

"That's right, that's the truth!" Zhang Shou slapped the podium and praised as soon as his words fell, but after praising it, he changed his words and said, "But has anyone ever thought about why this is?" ”

Hearing the three words again, Lu Sanlang was already numb in his scalp, and even the fourth prince was stunned. Or the third prince has been trying to keep up with Zhang Shou's rhythm, and at this time he didn't notice that most of the others looked dumbfounded, but he said thoughtfully: "Is it because after kicking this kick, it is as if it was pressed with your hands, and those grains are tighter in the hu?" ”

"That's pretty much it. Millet is an irregular object, so when poured into the dunk, there is often a gap between the millet and the millet, so the volume occupied will actually be relatively large. And kicking so hard, the millet in the Hu will be hit by a strong impact, and the arrangement between each other will change, and those originally large gaps will be filled, and the gaps in the middle of them have been reduced, so the millet that was originally level with the mouth of the Hu will naturally not be so full. ”

"Therefore, the weight of the same grain is different. The approximate density of an object that is not monolithic such as a grain can be measured by repeatedly kicking and smoothing out, as in the case of a drenched tip, but it can also be calculated simply when it is full. Then, weigh the grain and divide it by the volume of the guanhu, which is the density, but most of the time we can call it, bulk density. ”

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