Chapter 459: Proof of atmospheric pressure

The principle of the pressure cooker is very simple for Shang Wen. But for Qin, who has just established an education and research system. This is still an unknown mystery. And it takes a process to find out. For example, this problem was discovered by Captain Ma Zhendong who was involved in meteorological observations, but he could not explain this phenomenon. Of course Shangwen knew what was going on.

The pressure cooker is composed of a pot body, a pot cover, a fusible sheet, a vent hole, a safety valve, a sealing rubber ring, and other new forms of venting channels. But now, steel materials are very in short supply. Don't say it's making a pot. Thinking of this, Shang Wen explained in his heart why it could not be popularized.

The generation of new materials requires a time process. The priority level is also different. These Shangwens are temporarily out of control, so they go to manufacture, and steel has become an important material for high pressure. Some key things Shangwen all use steel instead. Such as vent holes. The pressure cooker needs a locking mechanism. This structure can be used on guns. But the emergence of thread cutters can solve this problem for Shangwen.

The pot body is made by stamping. Rather than making it by hand. Before the Qin State Arsenal, there was an "iron helmet" that was stamped from a whole iron plate to block bullets. But the individual equipment is already very high. Equipped with "Iron Helmet." Obviously not cost-effective. Ever since, was abandoned. Production molds are changed to production iron pots. Casting iron pots consumes coal abnormally. The price of coal needs to be shipped from the far north. Therefore, Qin's pots began to be stamped with medium-sized ones.

The pressure cooker is finished. The workers don't understand what this thing is used for. Shang Wen didn't want to explain, so he did an experiment himself. Cook the meat.

The same weight, the same water, the same fire. It takes a short time to open that pot. Don't guess the result.

The pressure cooker naturally wins.

"What is this?" King Qin asked, putting down the evening paper in his hand. Zhao Gao gently put down the end plate in his hand and replied.

"My lord, this is the chicken soup sent by the princess. Her Royal Highness made it personally." Zhao Gao said.

"Oh. Yu'er will cook the soup too. The widow will taste it." Then, King Qin put down the newspaper in his hand, and the current King Qin handed over most of the things to Shangwen. And he only has to check it at any time. With the emergence of newspapers, a certain degree of transparency began to appear in politics. King Qin read the newspaper every day, which is actually equivalent to understanding all aspects of Qin. Decentralization must be under certain supervision before King Qin dared to do so.

"En." King Qin took a sip of the jade spoon.

"My lord, how is it?" Zhao Guo asked in a low voice.

King Qin swallowed more painfully.

"The fire is almost too late." King Qin said. In fact, Yingyu puts too much salt. After Meier put the condiments, she got out the salt in advance. However, Yingyu saw that there was too little salt, so she added another spoonful. And it's a spoonful. Everyone wants to try, but Yingyu thinks it's done, so she directly gives it to Shangwen. Shang Wen didn't move. Then send it to King Qin. Only King Qin suffered. However, as a father, he is naturally happy for his children to be able to cook soup and filial piety. Even if there is something wrong, he naturally doesn't say anything.

Ying Yu, who was eavesdropping outside the window, whispered. "That's not right. I have been boiled for more than two hours, and it should be over."

"The principle of the pressure cooker is very simple, because the boiling point of water is affected by the air pressure. The higher the pressure, the higher the boiling point. On the mountains and plateaus, the pressure is less than 1 atmosphere, and water can boil at less than 100℃. Eggs are made in ordinary pots. The utensils are not cooked. When the air pressure is greater than 1 atmosphere, the water will not boil at a temperature higher than 100°C. The pressure cooker commonly used by people is designed using this principle. The pressure cooker seals the water quite tightly, and the water is heated. The water vapor produced by evaporation cannot diffuse into the air and can only be kept in the pressure cooker. This makes the pressure inside the pressure cooker higher than 1 atmosphere, and also makes the water boil when it is higher than 100℃, so that high temperature and high pressure are formed inside the pressure cooker. It’s easy to cook the rice quickly. Of course, the pressure in the pressure cooker will not be unlimited, or it will become a bomb.” Shang Wen explained to everyone.

"This is called atmospheric pressure so powerful!" the workers exclaimed.

"Atmospheric pressure exists naturally, not human." Shang Wen explained patiently.

"Oh." Everyone nodded. Seeing everyone still seems to understand. Shangwen believes that it seems that Qin's physics is in urgent need of strides. Otherwise, if you don't even know the atmospheric pressure, then the following experiments will not be done at all. Because it is this pressurization and decompression that gives chemistry a means of testing, so as to extract a large amount of chemical industrial products from petroleum and coal. Many of these industrial products are necessary for weapons.

There are many experiments that prove the atmospheric pressure. For example, the most famous one is the Ma Debao Hemisphere Experiment. There is also the Torricelli experiment. This experiment measured the value of atmospheric pressure. Shangwen decided to follow the example of Mayor Ma Debao and openly conduct this experiment.

Shang Wen drew a drawing and asked the workers to make it. At the same time, Shangwen asked about the pumping device. The answer is yes. Because many places have begun to use pumps. It has been used on the train. It's just that people don't know the principle. After understanding this situation, Shangwen decided to make it himself.

The rubber ring was used in the Ma Debao experiment. Shang Wen does not have such materials. Shang Wen has experimented with various sealing materials. Most of Qin's sealing materials are graphite, steel ring or other materials. The most expensive material is undoubtedly resin, which contains a lot of rosin and so on. At the same time, there are also animal gelatin extracted from animal bones, that is, capsules.

In order to do this experiment, Shangwen had to use a mixture of resin and gelatin, because the experiment failed anyway. Shangwen especially uses leather as the sealing material.

Two 13-inch copper **** are filled with water under a special seal and combined. Then pump the water out to make it a vacuum. Then let Mara do it. However, it is early morning. It is impossible for everyone to see it. As a last resort, Shangwen could only open the pumping place. Return to normal values. Without an audience, meaning is lost.

But Shang Wen decided. This experiment will be carried out tomorrow afternoon. Shangwen notified the major newspapers of the news. The newspaper has dedicated personnel on duty. They are in charge of the morning paper, because every day when the big clock points to six. The newspaper must be distributed to every household that subscribes.

When the newspaper received the news, it was already four o'clock in the morning. The printing of the newspaper has already begun. In order to grab the advantage of the news, they had to publish another special issue. Announce the news.