The heavy rain continued from the afternoon to the evening, but it still didn't stop. After dinner, Wan Lei had to discuss with everyone the "thunder and lightning" collected today. In fact, Wan Lei made a lot of preparations in advance for collecting thunder and lightning this time, especially
A simple "battery" was made, consisting of lead, lead dioxide and sulfuric acid.
Compared with steel, which is difficult to refine, lead is very easy to produce and is easily available on the market. Its melting point is relatively low, only about 300 degrees, and it can be melted into lead water in a briquette furnace.
It is easy to shape. In the chemical industry, it is often used to make pipes and reaction tanks. Sulfuric acid is produced in lead containers.
Of course, lead has many uses, such as lead white for cosmetics, lead for printing, and more importantly, it can be used to make batteries. Fortunately, Wan Lei made a diversion device in advance, and the lightning introduced into the battery is just
A very weak branch, otherwise this simple little thing will definitely be broken.
However, because the lightning duration is very short, there is not much electric energy stored in the battery. It may be suitable for doing some small experiments, but it cannot produce high-voltage arcs. Otherwise, Wan Lei would have built an electric arc furnace to make steel long ago.
.The first experiment is the electromagnetic induction experiment. The purpose of this experiment is to reveal the intrinsic connection between electricity and magnetism, and to lay the experimental foundation for the mutual conversion between electricity and magnetism, and to open the way for the invention of generators.
Under the attention of everyone, Wan Lei took out a small needle-shaped magnetic needle and placed it under a copper wire. After it stopped moving, everyone held their breath and concentrated. Wan Lei connected the circuit, and the small magnetic needle began to tilt slowly.
Everyone was surprised when they saw it. Wan Lei turned off the switch again, and the small magnetic needle slowly returned to its original position, as if an invisible hand was pushing it.
Pulling it down, Wan Lei replaced a piece of copper wire with a piece of copper coil that had been wound in advance, and then turned on the electricity. The small magnetic needle next to it suddenly deflected, and the onlookers were even more amazed. Zhao Xueer has always had many hands, and she saw
Wan Lei was having so much fun that he wanted to play too, so he grabbed the control switch and started playing with it.
However, after playing for a while, she felt bored, and the power was getting more and more low. It seemed that the small amount of power in the battery was almost exhausted.
"Sir, what's the use of doing this experiment?" Miao Yi blinked his big eyes and asked.
"The purpose of this experiment is to prove that electricity and magnetism can be converted into each other. Electric current can produce a magnetic field. At the same time, the movement of wires cutting magnetic wires can also produce electric current. Think about it, if we can create a generator that can produce powerful
And stable current, that would be a great thing."
"Tch, what's so great about it? Current has no use other than generating a magnetic field." After playing with the discharge in the battery, Zhao Xueer also finished playing with it, and she couldn't help but feel a little discouraged.
"Electricity has many uses. Electric energy can be used to heat objects, to illuminate, to do metallurgy, and can even be used to make telephones so that people thousands of miles away can talk. More importantly, it can drive motors,
Make it into an electric motor and provide us with strong power. In short, with electricity, everything is possible!"
"Is it true? Is there a phone that can make calls thousands of miles away? Isn't that the legendary Shunfeng Ear?" Zhao Xueer naturally didn't believe it.
"Sound ears are nothing. With the development of technology in the future, it is not impossible to invent a video phone. Through video calls, two people thousands of miles apart can talk face to face. It is like having the two divine powers of clairvoyance and ears at the same time."
"Wow, the more you talk, the more you talk about it. You can't be deceiving people." Not only Zhao Xueer didn't believe it, but other people's eyes widened. What Wan Lei said was nothing more than a fairy tale to them.
"It doesn't matter if you don't believe it, we can do the experiment." Wan Lei took out two small iron cylinders with a long string in the middle. He handed an iron cylinder to Zhao Xueer and said: "Go outside the experiment and whisper to the iron cylinder.
, I can hear it here, if you don’t believe it, give it a try.”
"Just try it. I think you are bragging about not paying the imperial tax." Zhao Xueer ran out of the laboratory in three steps and two steps at a time, chattering at the iron tube for a while, then ran back and asked: "Tell me, what did I just do?
What did you say?"
"You said Brother Wan is a big bad guy who likes to lie to little girls." Wan Lei said with a smile. Everyone looked at Zhao Xueer, but they saw her face was suspicious and said: "That doesn't count. You guessed it right."
After saying that, she ran out again. After a while, she ran back and asked, "What did I say this time?"
"This time, you didn't say anything, only the sound of grinding your teeth."
"Eh, no, you must have cheated." Zhao Xueer was not convinced, but Wan Lei put the iron tube in her hand to her ear, and then whispered to the iron tube in his hand, she said "Ah"
With a loud sound, he hurriedly threw away the iron cylinder and said angrily: "Do you want to deafen me?"
Wan Lei smiled slightly, ignored Zhao Xueer who was still protesting loudly, and said to the students: "This is still called a microphone, also called a telephone. Sound is actually a shock wave. In the air, the shock wave will weaken, so
It's like throwing a stone into the water. The farther the wave travels, the weaker the wave is, so if you are farther away, you will not be able to hear clearly."
"The principle of the telephone is almost the same as this microphone. It uses a device to convert sound waves into current fluctuations. The current can be transmitted to very far places in the wire without weakening, and there is a device to convert the current fluctuations into sound waves.
, you can hear sounds coming from far away places.”
"It's so troublesome to go around and around, it's better to write a letter directly." Zhao Xue'er was still picking out her ears. Apparently, the shock just now almost didn't deafen her, and her voice was a lot louder.
"Writing a letter is troublesome. You have to put what you want to say into words, and then ask someone to help deliver it. By the time the letter is delivered, it will be a year and a half ago. If it is just a love letter between a man and a woman, then it doesn't matter.
If you delay harvesting for a few days, you will only get lovesick at most. If it is an emergency
It would be terrible to have military information. I don’t know how many people will die in a few days. If you have a phone, you can report the military information as soon as you have it. After the headquarters receives the report, you can immediately forward the order to the various ministries. In this way, you can
Better direct the battle on the front line."
"You said this phone is so good, can you make it?" Zhao Xueer couldn't say it and started to roll her eyes.
"Hey, as long as there is electricity, what's the difficulty in inventing a few telephones?" Wan Lei said nonchalantly, because he understood the principle of telephones in middle school. After experimenting a few times or dozens of times, no matter what, he couldn't
The key to getting a few simple dedicated telephone lines is to have electricity.
"I can only say, do you have electricity now?" Zhao Xueer retorted.
"As soon as I have free time, I will lock myself in the laboratory and won't go out until I get the generator out." Wan Lei made up his mind. He still vaguely remembered the hand-cranked generator used in physics experiments in junior high school.
, draw the drawings and follow them, it should not be difficult to come up with an experimental model.
However, the current generated by the generator must reach a certain frequency and voltage before it can be used. The difficulty lies in this. This cannot be done quickly. Wan Lei studied chemical engineering, not an electrician. I am afraid it will take hundreds of times.
Even thousands of experiments may not be successful. Moreover, something like electricity must not only be able to emit electricity, but also must have a power distribution system, otherwise it cannot be used.
However, if you want to speed up the process of civilization, you have to do it no matter how difficult it is. Even if it means selling the iron, Wan Lei can do it. If it doesn't work in one year, he can do it in two years. If it doesn't work in two years, he can do it in three years. Even if it takes a lifetime, he can do it.
No matter what.
When Wan Lei was about to explain the principle of converting magnetic energy into electrical energy to the students, there was a hurried knock on the door. Zhao Quanzhong hurried to answer the door, and saw an orderly soldier coming in a hurry and shouting in Wan Lei's ears.
He whispered a few words. Wan Lei frowned and said to the students: "You continue to review, I will be back soon."
Wan Lei was so anxious because something happened in the city. Not long ago, dozens of people sneaked into the east of the city on a rainy night. When they found no one at the city gate, they opened the city gate and attracted nearly a thousand accomplices.
Entering the city, only a few dozen meters into the city, we were surrounded by the city's defenders, and a fierce siege and annihilation battle was now underway.
When Wan Lei rushed to the battlefield, he found that the battle was over. Dozens of corpses were lying on the ground. Nearly a thousand enemy soldiers were tied up and thrown to the ground beside the city wall. Only a few of the defenders were injured. It can be said that
It was a completely victorious battle of encirclement and annihilation.
"Mr. Wan has a clever plan. These guys are really evil and dare to attack." The person directing the battle at the scene was a military commander. He had already received a secret order from Wan Lei, asking him to guard the city in the past few days.
Tighten it internally to create the illusion that the city defense is empty and lure the enemy into taking the bait.
Unexpectedly, before the day had passed, these stupid enemies with no initiative came to steal the city again. Naturally, they were caught by the well-prepared defenders. The war just now was nothing at all.
Fighting, because these enemies did not even have weapons in their hands, most of them only had sticks. They were beaten by the defenders in a battle formation, killing dozens of them. Others suddenly lost all fighting spirit and threw down their "weapons".
Surrendered.
Wan Lei didn't like this kind of enemy who came into the enemy's nest after being let go. He glanced at the thousands of prisoners, frowned and said: "Pull them down for interrogation, find out the mastermind and internal agents, and deal with them according to military law."
, the others were put in shackles and led to build the city."
"Yes, such people who are dishonest and ignorant should be severely punished. If we don't show them some shame, they will think that our Peking Army is easy to bully." All the officers and soldiers agreed, and for these little thieves, they must be punished.
They all felt that it was not worth it to lie in wait in the rain for so long.
"Quickly clean up the battlefield and restore the city defense." Wan Lei gave the order, and the troops began to get busy.
In fact, one of the purposes of Wan Lei in letting these prisoners out was to play cat and mouse so that the Peiping Army would have targets for training. The scouts sent by Wan Lei have already found out that about 4,000 people are still stranded in Shuntian Mansion. Tonight
Only a thousand people came to attack, and the others must have found a place to kill themselves.
The city defenders played for a while, and then it was the cavalry outside the city's turn to appear. They had been training for so long, and they had to pull out mules and horses for a walk. Wan Lei also knew that this was taking a risk and would cause Peking to suffer a lot.
The army suffered unnecessary casualties. However, only through actual combat exercises with real swords and guns can a strong army be trained. If the Peking Army cannot even deal with these petty thieves, it will have to strengthen military training.
In addition, Wan Lei also knew that this risk had to be taken. Even if there were not these released prisoners, there would be other thieves sneaking into Shuntian Mansion in the future. Using these prisoners to practice now can be regarded as accumulating combat experience, so that they can sweep away the enemy in the future.
The bandits can get what they want, so why not do it.