Daming: I, Yang Xian, really govern Yang!

Chapter 169 Summer of the fifth year of Hongwu

Peking is also the capital of the Yuan Dynasty.

As the capital of the Yuan Dynasty, its city wall defenses were already very strong.And Yang Xian's improvement plan directly gave Beiping City the strongest and tallest city wall in the world!

Once completed, it is no exaggeration to say that it is impregnable.

Wang Baobao could only pray that he would launch the attack earlier. If it was too late, there would be no hope at all.

At that time, looking at the towering city wall, I am afraid that I will immediately despair.

Building the city wall was a big project, so Yang Xian sent Liu Kun to Peiping with a key team to take charge of the construction work.

Military factory, train station.

All people and things seemed to be put on clockwork, and started to operate step by step.

In the summer of Hongwu's fifth year, in addition to the above major events.

Yang Xian also did a trivial thing and built an ice-making factory in Yangzhou.

As for the reason why I suddenly thought of building this ice-making factory, it is a very funny thing.

In Rugao County, Yangzhou Prefecture, someone was selling counterfeit white sugar and rock sugar. He was reported and finally arrested by the Rugao County yamen. After some investigation, it was discovered that, good guy, this person actually used Glauber's Salt as white sugar for sale.

This matter was naturally reported to Yang Xian.

After Yang Xian took the people to Yangzhou for interrogation, he learned that they were a gang committing the crime and actually discovered a natural Glauber's salt mine in Fengyang Mansion.

Yang Xian was overjoyed, knowing that high-purity Glauber's salt can greatly increase the power of gunpowder.

Then Yang Xian directly asked people to go to Fengyang Mansion to take over the Glauber's Salt Mine on the pretext that the Ordnance Bureau was manufacturing firearms.

Fengyang Mansion was naturally reluctant at first, but Prince Zhu Biao came forward and solved the problem directly.

Just kidding, this is related to the development of firearms and the fate of the Ming Dynasty.

While taking over the Glauber's Salt Mine and making gunpowder, Yang Xian suddenly thought of making ice, so he also built an ice-making factory.

You must know that in the lives of ancient people, ice cubes, which may seem inconspicuous, were actually a very important consumer product.

In ancient history, "eating ice" was a great enjoyment of the ancients. Especially since the Song Dynasty, a large number of cold drinks came from the palace to the people.In big cities during the Ming and Qing Dynasties, "ice sellers" were a common sight in the streets in summer. During the hot season, the price of ice cubes often went up. In the midsummer of the Qianlong period, a pound of ice cubes even sold for 500 yuan. Money.

In addition to daily uses such as eating and cooling down in summer.

Ice cubes are also widely used in various fields such as ancient medicine and refrigeration.

For example, during the Wanli period of the Ming Dynasty, ice cubes also contributed to a "price miracle".

"Wuzazu" records that in Beijing in the early Wanli period of the Ming Dynasty, fish, crabs and other aquatic products were treasures, and their prices were much higher than pork, beef, and mutton.But in less than 20 years, the market has been full of fish, crabs and other aquatic products, and prices have been falling, making them much cheaper than pork, beef and mutton.

Why is this so?Because a large number of "chilled boats" along the coast purchase ice and go out to sea to preserve the caught aquatic products with ice and sell them to the mainland, the aquatic products on the market have increased sharply and the prices have become "friendly to the people".

Therefore, the ancients actually had a huge "rigorous need" for ice.

It can be used in all walks of life, the difference is whether it can be afforded or not.There were no refrigerators in ancient times.

Therefore, most of them use natural ice, which comes from only one source: ice harvesting.

The ice harvesting industry in ancient China can be said to have a long history. In the Zhou Dynasty, there was an official "Ling Ren" who was in charge of "ice harvesting". There is also a chant in the "Book of Songs" about "ice cutting on the second day of the year", that is, on the twelfth day of the lunar calendar every year. The coldest month of the month is the time for "ice harvesting". Archaeologists also discovered a "ling chamber" specially used to hide ice in the No. 5 site of Chang'an City in the Han Dynasty in Xi'an. Its internal structure design is very scientific.

With the advancement of ice harvesting and ice storage, the ice production of Chinese dynasties has been increasing day by day, and the consumer group has been expanding day by day. By now, the ice harvesting and ice storage technology of the Ming Dynasty has become unprecedentedly mature.

There are 23 official ice cellars throughout the capital, storing about 20 tons of ice every year.

Therefore, when he heard that Yang Xian was going to build an ice factory, Lu Mingyi thought that Yang Xian was going to build an ice cellar.

"It's a pity that the temperature in the south is higher in winter and the river freezing period is shorter, so the amount of ice is limited." Lu Mingyi said.

Yang Xian glanced at Lu Mingyi and said with a smile: "Brother Lu, you misunderstood. I don't want to build an ice cellar. I want to build a factory to make ice cubes."

"The kind made out of thin air." Yang Xian said and gestured towards Lu Mingyi.

"Do you want to use the boiling water ice-making method recorded in "Huainan Wanbi Shu"?" Lu Mingyi asked.

Since following Yang Xian, in the past two years, he has also begun to like to read this kind of leisure books that he used to think of to increase his knowledge.

Yang Xian shook his head.

The "summer ice-making" technology recorded in the "Huainan Wanbi Shu" mentioned by Lu Mingyi just mentioned was often written down in various historical fictional novels and time-travel novels as the protagonist's ice-making method in the early years.

It is recorded in the book that "Put the boiling soup in an urn, seal it with a new seal, and let it turn into ice in three days."

That is to say, pour the boiled water into a large urn, seal it, and then sink it into the well water for three days and three nights to get ice cubes in the hot summer.Although this technology is feasible from the perspective of physical science, in actual operation, it has extremely high requirements on air humidity, container volume, water temperature, etc. Even if it can make ice, the output is not high.

In later generations, someone wanted to replicate this experiment in the laboratory.

The final result is that if you want to make ice through "summer ice making", the air temperature needs to be around 20°C, the humidity needs to be less than 26%, and the volume of the jar should be at least about 100 liters. When every step is controlled perfectly , to get a few strands of ice residue.You must know that this is the optimal solution obtained after repeated experiments in modern scientific laboratories of later generations.

Thinking about it, if this method is really feasible, then so many dynasties after the Han Dynasty would not need to still use the most primitive method of collecting ice.

"This is what I want to use." Yang Xian said and took out a transparent glass bottle from behind. The bottle contained white crystals, which looked like sugar at first glance.

"This is?" Lu Mingyi had a puzzled look on his face.

"Do you still remember the case reported in Rugao County a few days ago?" Yang Xian laughed.

Hearing what Yang Xian said, Lu Mingyi immediately remembered it and said, "It's Glauber's salt. Sir, are you saying that Glauber's salt can make ice?"

"Yes." Yang Xian nodded and smiled.

In Yang Xian's view, the original ice harvesting method not only consumes a lot of manpower, but is also inefficient and is also affected by weather.

Far from directly manufactured incense.

(End of this chapter)