Chongzhen revived the Ming Dynasty

"The Leaning Tower of Pisa experiment?"

Xu Guangqi was completely confused.

Because he had never heard missionaries talk about this experiment, nor had Sun Yuanhua, who had returned from his mission to the West and had interacted with Galileo, mentioned it.

This made him curious and ask:

"What kind of experiment is this?"

"How come I've never heard of it?"

"Never heard of it?" Zhu Youjian was very surprised.

In his mind, this experiment should be quite famous, so why hasn't it started yet?
However, he was misled by elementary school textbooks. The experiment in the article "Two Iron Balls Landing at the Same Time" was never actually carried out.

Galileo's theory was put forward in "Dialogue Concerning the Two Chief World Systems," a book that has just been published in the West.

According to the theory of free fall, all objects, regardless of their weight or density, will accelerate uniformly in exactly the same way in a vacuum.

To make it easier for people to understand, Galileo had Salviati, who represented himself, explain this theory in a fictional dialogue in his "Dialogues":

“Aristotle said: ‘A 100-pound iron ball dropped from a height of 100 cubits will hit the ground sooner than a 1-pound iron ball dropped from the same height, which will only descend one cubit in the same amount of time.’ But I would say they arrive at the ground at the same moment.”

This was entirely the result of his theoretical derivation, but he had never conducted any experiments.

Zhu Youjian was unaware of this, but after hearing from Xu Guangqi that no experiments had been conducted at the Leaning Tower of Pisa, he immediately decided:

"If the West hasn't done it before, we'll do it ourselves."

"Prepare iron balls of the same material but different weights and sizes, as well as iron balls and wooden balls of the same weight but different sizes."

"Let's drop them from hot air balloons and see who hits the ground first, then figure out the underlying principles."

"Whoever can explain and calculate it mathematically will be granted a hereditary knighthood and membership in the Academy of Sciences!"

Xu Guangqi was appointed as a Grand Secretary to oversee this experiment in order to promote scientific research.

Xu Guangqi was still puzzled, but he knew that the emperor's intentions were good.

The spread of this experiment's fame can increase people's attention to science.

It can also shift the focus of attention and reduce the criticism one receives.

If Western learning can be used to explain the principle behind this experiment, the situation of Western learning will also improve.

He decided to take charge of the experiment as requested by the emperor, to find out the underlying principles.

To prevent anyone from being unable to answer, Zhu Youjian offered a slight hint, saying:

"This experiment can be called a free fall experiment, which is mainly affected by gravity and buoyancy, or air resistance."

"Air allows hot air balloons to float; it has power. Just as water can float objects, air has buoyancy."

"This buoyancy is not enough to make the iron ball and the wooden ball float in the air, but it will create resistance when they fall."

"According to my estimation, iron balls of the same material would probably land at the same time if they were to fall."

"There might be some differences due to resistance, but it's hard to distinguish with the naked eye."

(The Leaning Tower of Pisa is 56.7 meters high. According to calculations, when the larger ball lands, the smaller ball is 2.42 meters above it. Under the acceleration of gravity, the iron ball's speed upon hitting the ground is close to 40 meters per second. The time it takes to fall from 2.42 meters is less than 0.1 seconds, which is difficult to distinguish with the naked eye.)

Xu Guangqi was even more bewildered, never expecting that the emperor would know these things.

He didn't know if the emperor was right or wrong, but intuitively he felt there was no problem.

However, it cannot be released until it is confirmed; he plans to wait until the experimental results are available before announcing them.

After carefully noting these down, Xu Guangqi asked:
"Then what's the point of using a wooden ball?"

"Did the wooden ball land at the same time as the iron ball?"

Zhu Youjian said:
"If two balls of the same weight but different sizes, an iron ball and a wooden ball, are dropped, the iron ball will definitely hit the ground first."

"Because the wooden ball is larger, it will experience greater resistance."

"The purpose of comparing the two is to make people feel the buoyancy."

"I have offered a reward for the hot air balloon for several years, but no one has been able to solve the problem. I will use this experiment to inspire them."

Zhu Youjian originally had high hopes for the reward offered for the hot air balloon.

However, after a period of excitement, the question was shelved because no one could solve it.

Therefore, Zhu Youjian used a wooden ball and an iron ball to visually demonstrate buoyancy. This also introduced concepts such as density, drag, and gravity, promoting physics research.

Of course, he used the name of "investigating things" to encourage scholars to investigate things and acquire knowledge, and to study the underlying principles.

After explaining the freefall experiment, Zhu Youjian remarked with emotion:
"The ideal environment for a free fall experiment is in a vacuum, which eliminates interference such as air resistance, and can be called a free fall experiment."

"That way, all objects, regardless of weight or density, will fall to the ground at the same time."

"But there is no such place in reality. We can only do this experiment when we fly into space in the future."

The word "space" was also an unfamiliar term to Xu Guangqi.

He knew the emperor didn't mean "particularly empty," but rather the extremely high sky. He immediately offered his advice:
The idea of ​​flying to the heavens is nothing but a myth.

"No one can know what's in the sky."

"Your Majesty should not devote yourself to such a vain and unrealistic matter, lest you waste your energy."

Zhu Youjian shook his head and said:
"Things in space are not just abstract concepts."

"According to the theory of buoyancy, the air becomes thinner as you go up, until there is nothing at all, and it becomes a complete vacuum."

"In such a place, people cannot breathe or survive. But free fall experiments are also unaffected by air."

"If future generations do go into space, I hope they will conduct experiments in a vacuum to verify the theory of free fall."

Let the person next to him record it as his expectation.

He hoped that after the development of the Ming Dynasty's productivity, it would be able to set its sights on space.

Humanity cannot remain confined to Earth forever; it must venture to the stars and the sea.

Such a grand goal was naturally beyond his sight; he could only place his hopes on future generations.

Hearing the emperor's words, Xu Guangqi was relieved. He knew the emperor wasn't pursuing brain transplants into space and was not recklessly sending people into the sky.

However, he was somewhat skeptical of the emperor's claim that the air became thinner as you went up until it became a vacuum.

At that time, the mainstream view in the West was that the air was filled with ether and that there was no vacuum at all.

Zhu Youjian chuckled upon hearing this.

Although he didn't know how Galileo's disciple Torricelli proved the vacuum, he knew how to create a vacuum since he had used vacuum bags to store clothes.

Thinking of the hand-operated water pump he had ordered people to develop, Zhu Youjian drew a diagram and said:
"Order Wensi Institute to make an air pump that can extract air."

"Also, prepare two hollow hemispheres, put them together and remove the air, and a vacuum will be created inside."

"Outside air will flow into a vacuum, and after being blocked, it will squeeze the two hemispheres together, so tightly that even several horses could not pull them apart."

"This experiment is the hemispherical experiment, which can prove the existence of vacuum and atmospheric pressure." "I hope someone can calculate atmospheric pressure and create more convenient vacuum pumps and vacuum bags to store food and slow down its spoilage."

"Both offered hereditary knighthoods, and the best candidate would be granted academician status based on their academic qualifications."

They then offered a reward to Xu Guangqi to lead the hemispherical experiment.

This experiment is even more difficult to understand, because Xu Guangqi could not imagine why several horses could not pull apart after the air was removed from the hemisphere.

He was worried that the emperor was wrong, so he decided to announce the reward after the experiment was conducted.

From these two bounties, he fully appreciated the emperor's emphasis on science.

In the future, as long as we can uncover the underlying principles and do a good job of investigating things to acquire knowledge, science can establish its position within Confucianism.

He could also reduce the criticism he received for his Western learning and become a founder of science.
-
With two experimental requirements in mind, Xu Guangqi sought out Chen Zilong to make arrangements.

Upon hearing this, Chen Zilong immediately said:
"The student union mobilized the Academy of Sciences and the Academy of Arts and Sciences to support the two experiments."

"Does the teacher have a plan for promoting the experiment?"

"Should we advertise it in the newspaper for a while first to attract more viewers?"

Xu Guangqi hesitated and said:

"What if the results of the experiment are different from what the Emperor said, and we can't offer a reward?"

Chen Zilong disagreed, saying:

"His Majesty is wise and exceptionally talented, and he also received guidance from Emperor Taizu and Emperor Chengzu in a dream."

"He's even been to the sky; he might have conducted free-fall experiments there."

"There's no way this could be wrong; His Majesty must be right!"

This is the idea of ​​many people. After Zhu Youjian continued to prove it with prophecies, many people have come to believe that he is a living god who can communicate with heaven.

Many young scholars, including Chen Zilong, believed that the emperor was the supreme god among men.

On the contrary, scholars like Xu Guangqi, who had more contact with the emperor, did not have as much reverence for him.

They were skeptical of the claim that the emperor was the supreme god on earth, but they simply did not object to it.

Upon hearing Chen Zilong's words, he opened his mouth wide and finally said:

"Let's do the free-fall experiment first!"

"Once the free-fall experiment proves it, then we'll conduct the hemispherical experiment."

"Iron balls and wooden balls are easy to prepare; have the Institute of Literature and Art make them as soon as possible."

Chen Zilong nodded and immediately went to the Wensi Academy to find someone to make arrangements.

Lü Xiang, who built the hot air balloon under the emperor's guidance and was thus granted the title of Yuanshi (a scholar-official rank), was very concerned about this.

The concept of buoyancy has troubled him a lot, and he also wants to explain the principle of hot air balloons.

Unfortunately, his knowledge was insufficient, and he was unable to explain buoyancy.

Upon learning that the freefall experiment was related to buoyancy, he personally led the ninth-level blacksmiths of the Academy of Arts and Sciences to create iron balls of varying sizes and weights.

Based on the weight of the small iron ball, he used his superb woodworking skills to select very light wood and make a wooden ball with the same weight as the iron ball, but much larger in volume.

These four balls are the equipment for the free-fall experiment.

There are also hot air balloons that carry them, which can rise to a height of fifty meters and drop them from the sky.

Thanks to Chen Zilong's vigorous promotion, many scholars and commoners in the capital became aware of the experiment.

Those who enjoy watching a spectacle gathered at Golden Terrace on October 1st to watch this experiment.

Chen Zilong volunteered to board the hot air balloon and shouted through a megaphone:
"Stay away, or you might get hit."

"You'll have to see this clearly later. Those who can understand the underlying principles can receive a hereditary knighthood."

Ignoring Xu Guangqi's instructions, they directly revealed the reward, attracting the audience's attention.

The onlookers, both scholars and commoners, widened their eyes when they heard that someone could be granted a noble title for making a reasonable argument.

Although the current emperor is very generous in bestowing titles, in addition to meritorious service, a hereditary knighthood requires a donation of 150,000 shi of grain.

The vast majority of people in the Ming Dynasty could not afford this amount of money and grain, so they were basically ineligible for noble titles.

Now that they heard about the opportunity to become hereditary knights, every single one of them stared intently at Chen Zilong in the hot air balloon, afraid of missing any details.

Chen Zilong instructed the guards from the Academy of Sciences to clear a space before weighing the iron and wooden balls on the golden platform, and then slowly floated up in a hot air balloon.

At this time, hot air balloons had become an indispensable piece of equipment for the Ming Dynasty's military and police due to their functions of artillery fire correction and city observation.

Its improvement speed is also very fast. Although Lü Xiang and others did not know the principle, they greatly improved its performance by using their experience, and it has become very safe.

In no time, Chen Zilong floated to a height of fifty meters in the air, using the markings on the rope.

Looking at the densely packed buildings and crowds around him, he truly felt a sense of awe and wonder at the vastness of the landscape.
"This hot air balloon is a wonderful thing. Who would have thought it could fly so easily?"

"I hope someone can explain buoyancy clearly and calculate it scientifically."

After muttering "May Your Majesty bless me," Chen Zilong first took the large and small iron balls and simultaneously released them from his hands, causing them to fall from the air.

People heard a loud "thud" as the two iron balls fell to the ground almost simultaneously.

This has caused some who firmly believe that the heavier iron ball should land first to begin to doubt.

Not long after, Chen Zilong brought out a small iron ball and a large wooden ball, and dropped the two balls of equal weight down in the same way.

This time, the two balls landed at different times. The wooden ball was noticeably slower and even deviated slightly upon landing due to the wind.

Most people were bewildered by the result, and many had no idea what the underlying principle was.
Seeing this, Chen Zilong hurriedly lowered the hot air balloon and loudly read out the reward through a megaphone.

Then it was announced that a hemispherical experiment would be held in ten days, also at Golden Terrace.

If someone explains the principle behind it, he will request a higher reward from the emperor.

However, this is obviously impossible, and most people have no idea about it, let alone be able to explain it through scientific calculations.

Many people are just watching the spectacle and using it as a topic of conversation.

This also led to even more people watching the hemispherical experiment ten days later.

When they saw that two horses, four horses, or even eight horses couldn't separate the two hemispheres that had been vacuumed, and that it took sixteen horses to pull them apart, they were all amazed and exclaimed in surprise.

Before conducting this experiment, they hadn't realized that air possessed power. This experiment fully demonstrated the power of air.

The concept of vacuum has come to the forefront of people's minds. Moreover, unlike its Buddhist connotations, it has become a scientific concept.

Many people have begun to study vacuum, especially vacuum pumps and vacuum bags, which seem very simple.

They hoped to find a convenient way to vacuum-preserve food in order to obtain the noble title offered by the emperor.

A scientific craze swept through the Ming Dynasty, with everyone discussing the investigation of things to gain knowledge and to uncover experimental principles.

Science's reputation grew ever stronger, becoming one of the most prominent fields of study in the Ming Dynasty. (End of Chapter)