Short video spoiler history: The beginning of modern warfare

Chapter 149 Water System

[Before running water was available, people mostly used well water. By the end of the Qing Dynasty, the number of registered residents in Beijing had reached 80, but there were only 1228 wells in total. One well had to supply water to at least 652 people, which shows how tight the water supply situation was.]

[The first water plant was not built due to such intense water pressure, but because ministers wanted to build a water plant that could put out fires. Fires often occurred in Beijing at that time. From 1865 to 1906, there were 40 recorded large-scale fires in 20 years.]

[Although there was a department called the Fire Bucket Department at that time, which was responsible for extinguishing fires, they had to bring back buckets of firewood from far away and put out the fire one by one, which was extremely inefficient. And Cixi had experienced all these fires.]

[So when Cixi heard about building a water plant to put out fires, she was supportive in principle, but if you asked her for money, you would be ignorant. The ministers then used the trick of "official supervision and business management" to pass the buck to the merchants. The merchants were not stupid either, and they argued back and forth with each other. In the end, the matter was done according to the water supply model, that is, after the water plant was built, water could be sold to the people on a normal basis.]

[In the 1908th year of Emperor Guangxu's reign (400), Beijing's first water plant, the Beijing Water Company, was established with Sunhe River in the east of Beijing as its source. Along with it were the Sunhe Water Plant responsible for sedimentation and purification and the Dongzhimen Water Plant responsible for bleaching and disinfection. The two water plants were connected by two mm steel pipes.]

[Beijing's first water tower was also built in the Dongzhimen Water Plant: Dongzhimen Water Tower. The bleached and disinfected water was pumped into the water tower by a high-pressure water pump, and the treated tap water was pressed into the water supply network through the pressure difference. The network was designed to be 20 meters long at the time, with more than 420 taps. It started from the northeast corner of Beijing and was laid around the city wall.]

[The main network cables are mostly 450mm diameter pipes. From the main network down are small main pipes with diameters of 200mm to 350mm, which are used to access various streets and large alleys. From here, they are connected to 80-150mm branch pipes leading to various small alleys, and finally connected to small pipes with a diameter of less than 50mm to the user's yard or the taps of various water stations.]

[According to the plan, residents need to buy water coupons to get water, which is now 5 cents per dan. They need to use the coupons to get water from the water station and then carry it back to the water tank at home. Because there are not enough taps, the tap water at that time is not directly connected to every household.]

[This solved the domestic water problem for about 16 people, but there are at least 80 people in the city. Logically, if more water plants were built, the entire population could be covered. Unfortunately, this is not possible because Beijing lacks water.]

[Not only Beijing, but also northern cities generally suffer from water shortage. From the late Qing Dynasty to the early days of the People's Republic of China, Beijing only had this one water plant. At the same time, Shanghai, which had relatively abundant water resources, already had 50 water plants.]

Jinling City, in front of Fengtian Palace.

"Is Cixi lacking fire in her five elements?"

"But at this time, the Qing Dynasty is almost about to perish, right?" Everyone couldn't help laughing. No wonder when it comes to building a water plant, they strongly support it in principle, but when asked about actual action, there is no such thing.

At the same time, we can see the decline of the empire, which could not even raise enough money to build a small water plant.

"Sedimentation, purification and disinfection are all understandable, but what substance is used in bleaching?" Zhu Biao couldn't help but say that sedimentation and purification can be understood literally, disinfection uses chlorine to kill bacteria and viruses, and what about bleaching?
"Is the water quality in Beijing very turbid? Why do we need to use bleach?" Everyone was confused. Could it be that the water in the river is like that of the Yellow River, with a lot of impurities?

But after all, everyone still wrote down these two steps. Then the water tower, high-pressure water pump, and the ins and outs of the water plant were optional.

"Pressure difference means water flows to lower places, right?"

"Can the water shortage problem be solved by the South-to-North Water Diversion Project?" Many people's eyes lit up, as if this made sense.

"The timing is not right." Many people still have some impression that the South-to-North Water Diversion Project did not take that long, and the Three North Shelterbelt Project spanned several decades.

Hexing Tea and Snack Shop.

All the diners were excited because they had not seen any wells when they were shown the city and the home before.

Especially for such a high floor, some people in the city have discussed the issue of the well, but the explanation has been hidden.
I just didn't expect that tap water was used.
"The water carriers know the pain of water!" A group of diners complained helplessly. For example, the public water wells in Jinling City are all equipped with shafts, and water can be pumped up by shaking the shafts. In the remote countryside, there is no such device, and water is still pumped up by sheer force.
Not only is it dangerous, it's also very damaging to your waist.

Some places simply use water from the river, but it still requires a lot of fetching.

Many of the people here have been carrying heavy loads since they were young, and their shoulders may have some problems due to carrying so much heavy loads.

"Yes. The water flows automatically as soon as you turn on the switch. It's really vivid."

“When will this become popular in Jinling City?” Seeing all the convenient facilities, even Manager Wan was envious.

"It's probably because water is so easy to come by that they pay so much attention to their appearance." Mr. Su also said with a smile. Otherwise, a bath would require so much water. If a family were to bathe every day, how much water would they have to carry?

[The solution at that time was to exploit groundwater. This technology was learned from the Soviet Union. With this technology, many inland water conservancy projects were started, and northern cities temporarily got rid of the water shortage dilemma.]

[At one time, all major cities rushed to build water plants, repair water towers, and lay pipelines. If some cities still retain these tall, funnel-like buildings, they are water towers. Some water towers are painted with blue and white stripes.]

[The function of the water tower has just been explained: it uses the pressure difference generated by its own height to transport the collected and processed tap water to various places around the tower, forming an independent water supply system. Once the switch is turned on, water will flow out.]

[This type of water tower also has a fatal flaw. For example, if I want to build a new floor that is higher than your water tower, then the water cannot reach the floors that are higher than the water tower because the pressure difference is not enough. If I want to re-water the extra-high floors, I have to build a taller water tower.]

[Obviously this design is unreasonable, so we simply put the water tank on the top of the water tower on the roof. This design perfectly solves the problem of pressure difference]

[Another very strange problem followed: the water pressure was extremely unstable, especially in low-rise residential buildings next to high-rise buildings. When the water pressure was low, it took 10 minutes to fill a basin of water, and when it was high, it hurt to hit the hands.]

[This question is very simple. In fact, after the tall public water tower is demolished, the lower water supply points may not need a water pressure pump to use water, but the houses on high floors must build their own water towers. When the higher floors pump water to their own water towers, the water in the pipes of the nearby lower floors will be pumped away.]

[The solution to this problem is very interesting. It is a math problem that we learned in primary and secondary school. There is an empty reservoir with a capacity of 8 liters. There is 2 liters of water in the reservoir. The water inlet takes in 0.4 liters of water per minute, and the water outlet discharges 0.2 liters of water per minute. How long will it take for the reservoir to be filled? ]

[This is the solution, which is to build a reservoir for secondary water supply. High-rise buildings can draw water from the reservoir to the rooftops of lower-floor residents without being affected. The standard at the time was that any building with a height of more than 12 meters and more than 6 floors must be designed and use secondary water supply facilities.]

[It seemed perfect until we discovered ground subsidence caused by excessive groundwater exploitation. In serious cases like Shanghai, the cumulative ground subsidence from 1921 to 1965 was as high as 1.98 meters. This level of subsidence would directly cause ground collapse and even affect the stability of high-rise buildings.] [The solution was the later South-to-North Water Diversion Project]

Tang Dynasty, Chang'an City.

Li Shimin's heart moved. Tianmu said that the various problems in the late Tang Dynasty included the depletion of water resources. The eight rivers were cut off and the surrounding desertification
However, this is only a cure and not a fundamental solution. Moreover, excessive exploitation of groundwater will lead to ground subsidence, which is not worth the cost.

A project as large as the South-to-North Water Diversion Project is not easy to build.

This is a dead end.

Li Shimin pondered silently: if the Tang Dynasty directly entered the Second Industrial Revolution and had various advanced equipment such as airplanes, artillery, tanks, missiles, etc., and was ahead of other countries, then it seemed that it would not matter where the capital was located; if other countries could also catch up and both sides had these weapons, it would still be the same where the capital was located.

Under the scrutiny of various advanced weapons and equipment, the strategic location of Chang'an does not seem as solid as imagined.

At least, the plane flew by casually.

Even without the natural barrier, Chang'an no longer had the advantage of being close to the sea, and because the grain transportation chain was too long, it actually had some disadvantages.

Jinling City, in front of Fengtian Palace.

Everyone was amazed when they saw the development and evolution of the tap water system, especially the problem that as the floors are built higher and higher, the disadvantages of the water tower will be exposed.

From the influence of black and white, we can infer that this was an influence from a long time ago and is probably rarely seen nowadays.

If Jinling City wants to build a tap water system at that time, the various problems and solutions mentioned today will serve as a good reference.

Everyone in the science department copied down the pictures and questions given by Tianmu. Tianmu said more than once that mathematics is very important.

So everyone copied down the questions, wanting to see what the math level was like in primary and secondary schools.

However, most people had not studied arithmetic, so the hall was quiet, but they began to sweat after two minutes.
When it comes to mathematics, if you know it, you know it, and if you don’t, you don’t know it, and you can’t pretend.

Sun Chuanshi's forehead was covered with sweat. Although he really wanted to complain about what a ridiculous math problem this was, he held back.

The imperial examinations in the Ming Dynasty were not like those in the Song Dynasty, which had other subjects such as arithmetic and medicine. There was only one subject, the Jinshi. Although the subjects were quickly corrected after the appearance of the sky curtain, the time was short after all, and arithmetic was rarely mentioned. Now I look at it and I am completely in the dark. I have no idea.

Zhu Yuanzhang knew that they were unreliable, so he looked at Liu Ji.

Liu Ji smiled slightly, obviously confident: "It's actually very simple."

Seeing that this statement was about to make everyone laugh, he continued: "The water reservoir is 8 liters, and there are 2 liters now, which means the gap is 6 liters. Every minute, 0.4 liters of water enters and 0.2 liters of water is discharged, which means the net water intake is 0.2 liters per minute."

"The net water intake is 5 liter in 1 minutes, and the deficit is 6 liters, which means the reservoir will be full in 30 minutes."

Liu Ji still had a smile on his face after he finished speaking. When it comes to arithmetic, he modestly calls himself second, and no one dares to claim to be first.

"Lord Chengyi, please tell me again." Someone said with gritted teeth. He was just listening and never thought it would be so simple.
Liu Ji was not angry and repeated it again. With the written answer, everyone's minds gradually came to understand.

"Ah~ I see."

Liu Ji didn't care whether they really understood it or not. The Mathematical Book of Tens that His Majesty had asked him to compile contained many "torturing" questions. This was just the beginning. Thinking of this, he smiled inwardly. He wondered how they would react when faced with the problem of pheasants and rabbits in the same cage in the future.

Jinling City.

Many people also copied down this question and wanted to try to see if they could solve it.

However, most people don’t even recognize the characters, even if they understand what others are repeating. Without special training, it is really difficult for them to think flexibly.

Some of them are more sensitive to this and can easily come up with the answer.

Many business owners are also confused, but if you replace the water reservoir with a wallet, the water inflow with revenue, and the water outflow with cost, then you can do it quickly.
"I didn't expect the math problems from my childhood to come back as boomerangs! [狗头]"

"In Guangzhou, everyone has the impression that there is no shortage of water in the south, but when I was a child, my family still had a water tank of about 2 cubic meters. In the 7s and 80s, Guangzhou often had water and power outages. Speaking of water towers, there is an inverted cone-shaped one on Yuexiu Mountain, which has now been demolished. "

"The running water pipes that we have only used in our rural areas in the 21st century were already used in Beijing during the Qing Dynasty."

"In the 21st century, there is still a well near our primary school. I even took students away when they were in primary school."

"Now that I think about it, there have been huge changes compared to the past. My parents' generation used well water. My generation often had water and power outages before 07. When there was a water outage, I would go to the house with a well to get water. When there was a power outage, my father would let me go to the grocery store to buy red candles to light. But simplicity has its advantages, that is, there are fewer worries. "

(End of this chapter)