The weather started to get hot at the end of April. After dinner, Wan Lei sat in the courtyard to enjoy the cool air. This courtyard was Wan Lei's residence in Peiping. Now that the war situation was uncertain, he naturally moved everyone into the city. I saw him
The wicker chair rocked gently and the cattail leaf fan flapped slowly, it was so relaxing.
Chi Xin and Chi Cheng were also in the yard. They took a flat water and an angle meter and kept looking at the sky. At this time, the sky was clear and the air was clear, which was also the best time to observe the celestial phenomena. However, the female Taoists such as Miaoyu did not.
In their leisure time, each of them was running a hand-made spinning machine, weaving cotton wicks to make wicks for candles.
Learning without forgetting production is Wan Lei's tradition of teaching apprentices. In this way, you can earn money and train your apprentices' hands-on ability. Practical teaching and applying what you have learned is the right way. Everyone is talking and laughing.
They were doing fine work on the ground, and the sound of the spinning wheel's chirping was so hypnotic that Wan Lei couldn't help but stretch. Wei'er, on the other hand, was diligent. She sat by a small oil lamp and sewed summer clothes, every stitch and every thread was perfect.
Sewing very carefully.
"Sir, it's been measured. Our current latitude is about 40 degrees." Chixin ran over to report excitedly.
"Well, that's good. You can use the North Star to determine latitude. Then you can find a way to determine longitude later, so that you can draw a more accurate longitude and latitude map."
"What's so difficult about this? We can determine the longitude by measuring the time when the sun is in the sky. For example, when the sun is in the sky here, it is twelve o'clock at noon. Fifteen degrees eastward, when the sun is in the sky, it is eleven o'clock.
Fifteen degrees to the west, when the sun is in the sky, it will be one o'clock in the afternoon." Miao Yi interrupted.
"Yes, yes, my little brain is really smart, so tell me, why is this happening?" Wan Lei asked happily, these kids don't forget to review at work, and they are nothing more than three good students.
"I know this." Wongyu replied: "The earth rotates once, and it takes exactly 24 hours a day. Since the earth rotates from west to east, we can see the sun rising in the east and setting in the west. It is precisely because of this
, at the same latitude, the sunrise time in the east is definitely earlier than that in the west.”
"Then why not measure longitude by the time when the sun rises, but when the sun is in the sky?"
"Because the length of day and night is different in winter and summer, the sunrise time cannot be accurate. What can be accurate is the solar noon. No matter whether it is a high latitude or a low latitude, the solar noon must be noon, and the sun is at its highest altitude at noon.
The shadow is the shortest and easier to observe than the sunrise." Miao Yi said.
"Well, that's right, but what is the most necessary thing for longitude determination?"
"We need a clock, a clock that can accurately measure time. If there is a clock, the longitude of Peiping will be set to zero, and noon will be set to twelve o'clock. After traveling fifteen degrees eastward, the time of noon there will become eleven.
Point. On the contrary, if the time at noon in a certain place is eleven o'clock, it will be fifteen degrees east longitude." Miao Yi said again.
"Yes, a clock is a tool for accurate timekeeping. We used to use a clock to keep time, but it was not accurate and the details were not detailed enough. Now, we have to design a new timekeeping tool."
"Sir, if we subdivide the timepiece into more grids, wouldn't it be possible to keep time accurately? Why do we need to design it separately?" Chixin asked.
"Using a clock to record time is really inaccurate. When we study physics and astronomy in the future, we will need to use precise timekeeping tools. The design now is to pave the way for future research, so the clock must be designed."
"Okay, but we don't have the relevant design drawings on hand. I'm afraid it will be difficult to get them out for a while." Chixin frowned.
"I have already concluded this in my mind, but if I want to make it happen, I need you to do more hands-on experiments."
Wan Lei already had a blueprint in mind. The electronic clock of later generations would be the most precise in keeping time, but with the current level of technology, it would definitely not be possible. Therefore, Wan Lei settled for the next best thing and built a Big Ben, which is a pendulum machine to be precise.
Clock. It is a timer that utilizes the isochrony of a pendulum and uses the pendulum as the core timekeeping device.
The mechanical power of this clock is provided by a weight, and the swing frequency of the escapement is controlled by a simple pendulum. An L-shaped rod connected to the escapement spindle extends toward the pendulum, and the head of the L-shaped rod is bifurcated.
It just blocks the rigid pendulum rod. When the pendulum swings, it drives the L-shaped rod to rotate, thereby transmitting the frequency of the swing to the escapement.
The advantage of the pendulum clock is that the frequency of the pendulum has nothing to do with the initial force pushing it, but is only related to gravity and the length of the pendulum. In this way, the timekeeping mechanism is really no longer interfered by the dynamic mechanism. In addition, you can also add
The hairspring controls the balance wheel. The hairspring is a spiral spring connected to the balance wheel. When the balance wheel moves towards a
The direction of rotation deforms the hairspring and generates a force to pull the balance wheel to rotate. After turning the balance position, the hairspring deforms again and generates a reverse force to pull the balance wheel back again. In this way, a kind of balance can be maintained.
It can vibrate periodically, like a horizontal pendulum or a simple pendulum, to control the frequency of the escapement.
The hairspring-balance wheel is independent of the power mechanism like the simple pendulum, and its frequency is not affected by other mechanical parts. The advantage of a clock made with a hairspring-balance wheel compared to a pendulum clock is that it does not rely on gravity. Therefore, as long as the design is reasonable, then
It can still keep accurate time while moving, which means it is relatively more portable and can accurately keep time even in the bumps on the carriage.
The principle seems simple, but it takes countless experiments to make such a clock. This tedious experimental work is naturally completed by a few students. Making clocks now is time-consuming and labor-intensive, but it can be considered
To gain experience in designing other machinery in the future, especially steam engines, Wan Lei has long wanted to own this kind of thing.
In order to invent reciprocating power machinery that converts steam energy into mechanical work as soon as possible, and even more advanced internal combustion engines, Wan Lei decided to guide these little guys and cultivate their hands-on invention abilities. Wan Lei did not dare to expect that all of them would be Edisons.
, but seven together can make half an Edison, which is amazing.
And just as Wan Lei was explaining the principle of the pendulum to the crowd, there was a knock on the door outside the courtyard, and then someone shouted: "Mr. Wan, there is something going on in the south of the city, please come over immediately."
"What's the matter?" Wan Lei immediately stood up from the rattan chair, threw away the rattan fan and went to answer the door. Zhao Xueer and others also dropped what they were doing and followed out.
"Battle Commander Zhang, who is responsible for guarding the south of the city, sent someone to report that a grain transport team has arrived from outside the city and is clamoring to enter the city." The person who came to deliver the order was a yamen servant. Seeing that Tie Xuan had also received the news immediately and
Rushed over.
"Grain transport team? Are you coming so late?" Wan Lei faintly smelled a hint of conspiracy, and immediately trotted out to the south of the city. As he walked, he said to Zhao Xueer and others: "You guys are going to other places.
Go to the city gate and tell the generals guarding the city to be on alert and guard the city carefully."
All the people left in response, and only Zhao Xueer followed Wan Lei as a bodyguard. The two of them rode horses and ran to the south of the city. They heard bursts of shouts of "Open the door and let us enter the city." They climbed up the tower and took a look.
Good guy, thousands of grain trucks are lined up outside the city, and there are at least tens of thousands of people responsible for escorting them.
"It's getting late at this time. As usual, the city gates cannot be opened. If you are tired, please spend the night outside the city." The guard on the city shouted.
"We have been traveling for a whole day. We have not had enough water and rice. We are tired and hungry. Please do us a favor and let us into the city." Seeing that shouting failed, the people outside the city turned to begging.
"We brought food here with good intentions, but you closed the door to us. Is this how you treat guests in Peiping?"
"Brothers, if we had known that Beiping City was so unkind, we should not have brought the grain here. Now we will bring it back and not give it to them."
The people below were clamoring to enter the city. Tie Xuan, who was on the top of the city, felt even more headache. When he saw Wan Lei coming, he said, "Xiannie, can this door be opened?"
"Open, why not open?!" Wan Lei raised the corners of his mouth and said nonchalantly.
"But, what if these people take the opportunity to seize the city..." This is what Tie Xuan is worried about.
"Follow the plan." Wan Lei whispered in Tie Xuan's ear and shouted outside the city: "Brothers, you have come a long way to work hard. The city gate will be opened soon. Please wait a moment."
"Hurry up and open the door. The night frost in the wild is so heavy that it will freeze us to death." The people from the city shouted again and urged.
However, Wan Lei ignored them and instead called for the commander of the city guard, Zhang Battalion Commander, and other generals. Everyone whispered in the room for a while, and then they went separately. Tie Xuan saw that Wan Lei had already made up his mind.
, didn't bother to ask any more questions, but just stayed on top of the city and didn't dare to leave.
About half an hour later, Wan Lei led a group of sergeants and carried dozens of big bags up to the city tower. After all preparations were completed, he waved his hand to signal the city gate to be opened. There was a "bang" and the suspension bridge was lowered.
At the same time, the city gate also opened wide.
At this time, Tie Xuan's heart was in his throat, fearing that the gang from outside the city would swarm in, but Wan Lei patted his hand and told him not to worry. In fact, Wan Lei had already prepared for those few
The items contained in the ten large boxes are to prevent intruders from taking over the city in one fell swoop. Now they have been placed on the top of the city to keep them unchanged in the face of any changes.
However, what Tie Xuan was worried about did not happen in the end. When the people outside the city saw the city gate opened, they not only stopped shouting, but also became very orderly. They drove the grain trucks and lined up towards the city gate. There was no riot at all.
This made Tie Xuan suddenly confused again, and the defenders on the top of the city also looked at Wan Lei. Wan Lei just smiled indifferently and waved his hand to indicate the second response plan.
The so-called second plan is to invite you into the urn. Wan Lei doesn't care whether the person coming is a spy or not, but he will treat him as a spy first. No, a small company commander immediately led people to push several carriages and got stuck at the city gate, and
Remove the steam from the carriage
The aroma of the old wine was flowing, and he shouted to the first grain man who entered the city: "Everyone has come from afar, but we at Shuntian Mansion have no respect for you. Please drink a glass of water and wine to warm yourself up before entering the city. Wait for it."
If you have good food, we will hold a banquet in honor of you."
"It's important to transport the grain into the city first. It's not too late to drink wine later." The grain man went to refuse.
"Oh, brother, you are just too polite. You are not afraid that the wine is poisonous. Okay, I will drink this bowl first." After the company commander finished speaking, he drank the whole bowl with a tilt of his neck and flashed the wine.
He picked up the bowl and said, "I promise it's not vegetarian. You can drink it with confidence now."
When the words came to this point, the grain man frowned and did not dare to shirk anymore. He took the wine bowl and drank it all in one gulp. Finally, he praised "good wine". The company commander laughed and looked at each other.
Feeling sorry for the late situation, he said a few more polite words before letting him enter the city.
Someone took the initiative, and the grain men below also followed suit. They were all poured a bowl of wine, and some of them used the strength of the wine to shirk it, but they could not withstand the insistence of the company commander who persuaded him to drink. In the end, he was beaten ten times in a row.
Several cartloads of wine would be enough to drink for this man who spent more than ten thousand dollars.
This was both to persuade people to drink and to arrange for people to enter the city. They were busy from midnight to the second half of the night. When all the grain men entered the city, the city gate slowly closed again. Wan Lei came down to the tower and asked the young company commander:
"How about it, everyone drank?"
"Drank them all."
"That's good. You should find a place to rest first. Don't fall down halfway."
This scene naturally fell into Tie Xuan's eyes. He didn't understand what Wan Lei wanted to do. He secretly thought in his heart: "Did he want to get these people drunk? This is not right. It was just a bowl of wine.