Three days have passed, and there are only two days left before the Mid-Autumn Festival.

Chen Xu also arranged the production of perfume one after another, not only arranged for people to continue to pick and collect a large number of osmanthus, chrysanthemums and various herbs, so that a group of alchemists in the chemical laboratory distilled and refined day and night, but also arranged for the glass factory to start producing larger distillation equipment and making crystal glass bottles of different colors.

The most complicated push-type spray cover Chen Xu specially went to the engineering college to gather some students and craftsmen for a class, explained the working principle, prepared to let these students and craftsmen start public relations research, and also proposed a huge reward of 5,000 yuan to stimulate the enthusiasm of all students and craftsmen.

The principle of the press type spray cap is very simple, in fact, it is a simple air pressure pump, Chen Xu was curious before and opened the spray cover of shampoo hand sanitizer to see, there is a coil spring in the closed air pressure bin as a recovery device, in fact, it is the same principle as the pump and bellows, after pressing, the gas in the air pressure bin is emptied, under the different air pressures inside and outside, the liquid in the bottle is squeezed out of the nozzle along the catheter, and the spring springs up after letting go, and the gas enters the air pressure bin and the bottle, and the internal and external pressure reaches a balance.

This principle seemed very simple to Chen Xu, but when he explained it, he found that everyone was listening to a book from heaven, with two eyes wide and their mouths wide open, looking at him dumbfounded like a group of Erha.

Air pressure is not a new word for these people, Chen Xu has mentioned it many times as early as when he first explained the topography and climate, it is precisely because of the different air pressure in different regions that there is the flow of wind, thus forming various climates such as rainfall, snow and even drought.

But after all, this is a very abstract statement, and everyone does not understand what the real air pressure is, because the air pressure cannot be seen at all, and therefore it is impossible to describe its specific existence and role in real life.

The idea of squeezing out the gas to get the water out of the bottle is bound to be unsuccessful in the eyes of all.

"Master Hou, how can the air pressure you said prove its existence? You also said that the air we live in is full of all kinds of gases, and we rely on oxygen to breathe to survive, but since ancient times, it has been believed that breathing is nature. Breathing is just the body exhaling the old and absorbing the new, not to breathe any oxygen from the air, and the air is empty and empty, how can the breath come from, once the breath is exhaled out of the body, it will disappear in an instant......" A craftsman with a bun stood up and retorted to Chen Xu.

In the Academy of Sciences system, everyone knows that when discussing problems, they can speak freely, whether they are right or wrong, they can raise questions and discuss them, but they must have their own ideas, and they cannot refute others for granted, that is, they cannot be pure trolls and bar spirits.

"Yes, the first child of a person is still in the mother's womb, and he can still develop and grow without breathing, so where does the oxygen that Hou Ye said come from......" Another Immortal Wind Dao Bone Mo disciple stood up and echoed.

"In the womb, of course, the human being receives oxygen from the mother through the umbilical cord......"

Chen Xu's words were interrupted before he could finish speaking.

"Master Hou, the baby is pregnant in the mother's womb, and it doesn't breathe because it has fetal breath, and the umbilical cord is only ...... by the power of the mother's blood."

"That's right, the reason why the fetus survives is because of the innate ancestral qi stored in the mother's body, which is called the innate vitality, and the fetus obtains the innate vitality through fetal breath to grow, and once the baby is born, the acupuncture points are opened, and it can breathe and breathe ......."

"Yes, yes, what Hou Ye said has no roots and no reason, and it is not scientific at all, it is really difficult to agree......"

Chen Xu: ......

I'm so unscientific, a bunch of stupid people who don't understand bullshit, what Lao Tzu said is science, okay, you heavenly diehards.

Chen Xu found that a group of people in the academy system are becoming more and more difficult to fool, and they used to believe what they said, and they listened to it with relish, but since the spirit of scientific skepticism began to spread, Chen Xu felt that every time he said some new theories, he would always be doubted, and if he couldn't come up with a proof method of seeing is believing, these people would jump very high.

And Chen Xu is also very depressed, it is really difficult to talk about science with a group of people who believe in metaphysics, because they are always easy to connect with the five elements of yin and yang and the Zhouyi Bagua to explain natural phenomena.

"Papapa ”

"Don't believe it, unless Master Hou can prove it to us?" Almost everyone in the classroom shook their heads in unison.

Chen Xu's face twitched a few times, and then he looked at the ceiling of the classroom at forty-five degrees for a long time and then nodded and said: "Okay, Ben Hou will prove to you today that air pressure exists, the power of air pressure can not only pump up water, but also open your eyes, you go find a curved water pipe to ......" Chen Xu pointed to a teacher sitting in the front row.

"Master Hou, how thick and long should it be?" Jiao Xi quickly stood up.

"Half an inch in diameter is enough, a few feet long is enough, but it must be curved!" After Chen Xu finished speaking, he pointed to the two students and said, "You two go and carry a bucket of water and an empty wooden bucket!" ”

The things Chen Xu wanted were quickly prepared, the bucket full of water was placed on the podium, the empty bucket was placed on a slightly lower stool, and a curved thin pipe was also found.

"If Ben Hou can transfer the water in the bucket to the empty bucket with this pipe in his hand without using any other items, you must not believe it, right?" Chen Xu took the water hose and showed it to everyone in the classroom.

Many people looked at each other and nodded their heads together.

Although many people have seen the water tower, the water tower drains water from the bottom, but at the moment Chen Xu only has a thin pipe, and judging from experience, there is no possibility of discharging the water from the wooden barrel into the empty barrel.

"Keep your eyes open, here are the moments to witness the miracle......"

Chen Xu put one end of the water pipe in the wooden bucket, ready to hold the pipe and sip two sips of water out, but after looking at the dirty pipe head, he didn't know what was stained, so he pointed to the guy who was the first to question him with a smile and said: "Come and cooperate with the test, inhale hard at this nozzle, remember, the mouth can't leak!" ”

"Yes, Master Hou!" This guy ran up with excitement and red skin, and without even looking at it, he inhaled sharply with the tube in his mouth, and then the tears that were choked by a stream of water came down.

And just as the craftsman let go of the pipe, everyone saw that there was a stream of water flowing out of the pipe, and it fell into the empty barrel with a clatter.

"Wow~~" There was a commotion in the classroom, almost everyone was rubbing their eyes thinking that they were dazzled, and after a while, the classroom began to be excited and noisy, and many people even left their seats and ran to the podium to watch, Chen Xu did not stop it, and warmly beckoned everyone to come up and observe.

"Master Hou, this ...... Could it be that you cast an immortal spell? A group of people were staring at the rushing water pipes, and one of the craftsmen said excitedly with a slight pendulum.

"It's not an immortal spell, Ben Hou uses scientific principles!" Chen Xu pouted.

"But I've never seen anything so strange that water can run from bucket to bucket on its own!"

"Hey, how can this water flow upward......"

"yes, it's weird, it's incredible......"

"Who said it wasn't, I feel like there's a ghost in this tube......"

"Hell, uncle!" Chen Xu kicked the craftsman who said there was a ghost in the ass, and then drove a group of guys back to his seat and said, "This is a simple physical phenomenon called the siphon principle......

"Master Hou, what is the siphon principle?" A craftsman asked aloud.

"Rainbow, is neon, neon you should have seen, after the summer rain, you can see an arc-shaped colorful halo in the sky, you see that the pipe in my hand is also curved, so I call the method of transferring water from one bucket to another is called the red siphon principle, which is a universal principle that applies everywhere, as long as one water surface is higher than the other water surface, the water will keep flowing high to the low, until the last two sides of the water level is the same high, if there is water high enough, The pipe is long enough that the water at high places can be drained at the end, and the key to the maintenance of this siphon principle is because of the dual effect of air pressure and water pressure! ”

"Master Hou, you have talked about water pressure and air pressure before, and it is not that we don't believe what you said, but even if you did this siphon principle experiment, where is the air pressure you are talking about?" A craftsman stood up and questioned again.

The so-called hearing is false and seeing is believing, but at the moment, even if they really saw Chen Xu just relying on a curved pipe to draw water from one bucket to another, they had to question further, because qi is something that cannot be seen or touched, and it is essentially different from water, so they can't completely solve their doubts, and even have more doubts.

"Ben Hou said before that gas is everywhere, although it can't be seen or touched, but it does exist, and there is gas in the water pipe, so after putting the water pipe into the water, because of the balance of air pressure, the water can't come out of the water pipe, but after I let the water pipe absorb the air in the water pipe, there is no air in the water pipe, and under the air pressure outside, the water will enter the water pipe......"

"Master Hou, in this way, the water coming out of the water pipe is not because of the air pressure, but because Fang Da's ears sucked the water out of the wooden barrel! Another craftsman stood up and said loudly.

"Yes, yes, the more the Hou Ye pulls it, the more complicated it becomes, and it is obvious that Master Fang sucked the water out with his mouth."

"Yes!"

Looking at the sound of doubts in the classroom, Chen Xu hated itchy, Nima dripped a gourd scoop, Lao Tzu shouldn't have preached any bullshit in the first place

The more the explanation becomes, the more complicated it becomes, and this experiment makes the problem more and more complicated.