future library.

Chapter 70 Elementary Mental Arithmetic Tutorial
The size of the Shen family is much larger than that of the Cheng family, but in terms of its influence and control in the capital, it is not yet one third of that of the Cheng family in Shaonan.The horse-drawn carriage with the flag of "Shen" couldn't even fully guarantee the ordinary nobles' access privileges - when passing through the second gate, there was actually a city guard collecting money.

Cheng Jinzhou, who is still familiar with the life of the nobility, couldn't help but widen his eyes.This kind of thing is not to mention the Great Xia Dynasty, which emphasized the difference in status. In a more mature era, it is normal for a gentleman with a special license plate to be stopped on the spot by a highway toll booth. , Lin Bo paid the money in a proper manner, but Shen Cong didn't say a word.

"The emperor's rules." Classmate Shen Cong explained guiltily, feeling that he had been embarrassed in front of the country nobles.

"I thought the nobles didn't have to pay taxes." Cheng Jinzhou insulted him in a flattering way, provoking the young master of the Shen family with his nostrils upturned.

In fact, not only nobles do not have to pay taxes, officials do not have to pay taxes, and gentlemen with fame do not have to pay taxes, nor do astrologists recognized by the Astrology Association. Huge tax-free class.On the bright side, it is also this tax-free class that supports the normal operation of the country-no benefit, who will support His Majesty the emperor to live a happy life.

Shen Cong blushed slightly because of his anger and said: "Our Emperor is crazy about money. The capital is okay, but he only sets up a card to collect money, and Hexi is worse. I heard that the transfer envoy will try a new tax law..."

"You know all of this?"

"There is no toilet without diapers." Shen Cong finally got rid of the topic just now.

The relationship between Cheng Jinzhou and Liu Bin can be said to be close, and he has no other way to learn about the court news, so he took the opportunity to ask carefully.

When a 17-year-old boy needs recognition from others and is eager to express himself, Cheng Jinzhou only needs to express admiration moderately, and Shen Cong can keep talking.The latter had nothing to worry about facing a 13-year-old child, and his face flushed with excitement as he danced and danced.Because the little bit of unhappiness brought by the city guards has long been thrown out of the sky.

For a while, classmate Shen Cong even felt that his new classmate was knowledgeable and interesting, and it would be good to train him as a younger brother.

……

Entering the warehouse area of ​​the wharf, the carriage jolted violently, and the people and vehicles coming and going made the speed suddenly slow down. The young men at work saw the banner of the nobility, except to give way, but very few deliberately avoided the road, perhaps the nobility of the capital There are too many of them, making them unavoidable while being familiar.

Because it was built on a water and land thoroughfare, although Xiajing's population is not one million, the area's supplies are richer. The West Pier built along the Jingzhou Canal stretches for more than ten miles, and the largest navigable ship is only three to four hundred tons. Under such circumstances, it is not an exaggeration to say that there are thousands of ships and thousands of sails.

Shen Cong hated the smell of fish, sweat and corruption wafting from the pier. He squeezed his nose and cursed something, jumped out of the car abruptly, and said viciously: "You'd better let me see something interesting, this place ..."

On the uneven ground, it is natural for boots to splash some muddy water, but soiling a pair of Nanhu silk uppers with small sheepskin turned Shaw's official boots is a bit expensive.Shen Cong frowned as if someone had molested him and said, "Shao's boots are not easy to buy."

"It's still a limited edition." Cheng Jinzhou was two heads lower than him, but he held his head high and said: "Uncle Lin, please lead the way. Have you got the sulfuric acid?"

"There are 4 jars of the stuff you call 'sour' in the shop. I don't know if it will go away. It has been delivered." Lin Bo laughed. The seventh-rank official in front of the prime minister's door said to a 13-year-old child. It's much more natural.

"That's fine." Cheng Jinzhou was satisfied that there was almost something he could fool.

The warehouse of the Shen family is in a very good location. After getting off the carriage, it is about 400 meters away. Due to the intentional removal, only one-third of the warehouse is filled with pottery, lacquerware and other goods, and there are two basketball courts in the free space. The size of the house, more than 300 stones of food were piled up in the corner of the door, it looked as if it had been abandoned.

Cheng Jinzhou picked up the wheat with his hand and looked at it for a moment, then said with satisfaction: "It's very good. I'm sorry to bother you."

The so-called practice makes perfect, he can more or less tell if some food is good or bad.

Lin Bo didn't know that he, a child, could understand or not, so he laughed, "It's just as long as the young master likes it."

For a family like the Shen family, court restrictions such as food reporting and other matters have no effect. When local officials want to claim their humble positions, there is no need to expect officials to question court officials about this.In the end, it is still a situation where the people do not appoint officials and do not investigate.Moreover, the transaction volume in the capital is huge, and it is difficult to keep accounts as clear as Shaonan's. Naturally, the Shen family is not as cautious as the Cheng family.

Cheng Jinzhou slightly rubbed the face of the ring, turned around and said with a smile, "Why don't you leave me alone inside?"

"I walked with you for half an hour, and all my clothes and shoes were scrapped. How dare you block me out?" Shen Cong made a silk scarf out of nowhere, and covered his face like Zorro in a third-level movie. He said with hatred: "In the Hongwen Museum, we are also number one."

"Where's sulfuric acid?" Cheng Jinzhou smiled casually. The latter saw him as easy to fool as a 13-year-old child, and he saw a 17-year-old child as such.

"In the corner over there, I'm worried about contaminating the food." Lin Bo said carefully.

Cheng Jinzhou looked around, and there were indeed 4 small jars piled up in the opposite corner, the size of a 10-jin shochu can.Walking a little further, you can smell the familiar pungent smell of sulfuric acid, Xiao Cheng covered his nose and laughed.

It is much more wonderful to encounter sulfuric acid while traveling through time than to meet old friends in a foreign land.

On the opened interface, the customer service 010 has been impatient for a long time, and urged: "If you are buying a book, there is a 7-word book, are you sure?"

Cheng Jinzhou turned his back to Young Master Shen, pretending to be looking at vitriol, and said while flipping his lips up and down: "Exchange a book with more words."

In his understanding, those with few words in libraries are mostly papers, magazines and pamphlets, while the better ones are "cultural relics" left over from previous generations.For him, compared to the timeliness and professionalism of papers, those books that have been summarized and matured may be more useful, although from another perspective, the content of the books must be uneven, and the chance of getting good things is not necessarily Increase, but Cheng Jinzhou still wants to try it. Previous experience has proved that if you only buy short books, it is difficult to find satisfactory content. If you finally find it, it will be like "Mechanical Metrology", only the first part , which is unpleasant to read.

Customer service 010 didn't need to study Cheng Jinzhou's psychology, and said straightforwardly: "If you want to determine the word count, then you have to relax the requirements in other aspects."

"I've heard too many things like quantum laws." Cheng Jinzhou curled his lips and said, "Then there's no need to determine the number of words, I'll decide by myself."

Last time, he played a similar game with Comrade Customer Service. Although both of them were so tired that they were foaming at the mouth, he obviously won.As a customer service, Comrade 010 definitely cannot compete with Cheng Jinzhou in training endurance. Seeing his tough attitude, he had no choice but to compromise: "12 characters, are you sure?"

"When I say yes later, we will trade again." After Cheng Jinzhou finished speaking, he brought out a jar of sulfuric acid wrapped in a rag, covering his nose with one hand and untying it with the other.

The first thing mixed in the air was a smell of sulfur. From the perspective of the nasal mucosa, there was no change in the whole.

"It's distilled and calcined." Cheng Jinzhou sighed. Although he has a PhD in theoretical physics who uses cheating as his main tool, simple chemistry is still not difficult for him.

The so-called distillation and calcination is to distill ferrous sulfate, which the Chinese call vitriol oil, in a sealed environment. The main purpose is to use high temperature to decompose ferrous sulfate, and let it decompose into sulfur dioxide and sulfur trioxide, the latter When mixed with water, it is sulfuric acid.A more advanced method is to find a way to convert sulfur dioxide into sulfur trioxide to increase its concentration. In the environment of the Great Xia Dynasty, if you smell the strong smell of sulfur dioxide, you basically know its production method.

"These four cans cost a lot of money." Cheng Jinzhou asked deliberately. Distillation and calcination consume a lot of artificial firewood, and the price cannot be as refreshing as in the industrial age.

"A jar of 3 taels of silver." Lin Bo replied beside him.

The price of a 10-pound bag costs two acres of land, but it is much cheaper than Cheng Jinzhou imagined.

Before he spoke, Shen Cong couldn't wait and said, "Don't worry about a small amount of money?"

Even though he was covering his nose, Student Shen still looked at the viscous liquid in the jar with curious eyes and wanted to touch it with his hands.

"It will cook." Cheng Jinzhou quickly grabbed him and said, "This thing can corrode iron."

After finishing speaking, he ordered: "Go and get a bigger basin, preferably ceramic, and then bring clean water.

"Will ceramics not rot? Is it not harmful to food?" Shen Cong looked at it curiously, and even showed a nostril.

Cheng Jinzhou ignored him.After a while, the servants brought two large stone troughs, one for storing water on the boat, and the other for drinking water for cattle and horses, both of which were more than two meters long. Water, Lin Bo asked with the same interest: "Is it enough?"

"That's enough, that's enough." Cheng Jinzhou said, calling another servant to carefully lift the sulfuric acid and slowly pour it into the stone trough.

An unpleasant white gas rose quickly, mixed with the stench accumulated in the stone trough for many years, like a mantis flying up.

Cheng Jinzhou casually grabbed two handfuls of wheat and threw it into the sulfuric acid, saying, "Look at how powerful it is."

The wheat fell into the trough and immediately turned black.The only thing that can compete with concentrated sulfuric acid dehydration is government taxation.

"What are you going to do? I see that other astrologists use many kinds of things to cook together." After all, Shen Cong came from a family, and he is well-informed in this era.

Cheng Jinzhou smiled and refused to explain, how could he really know any astrology and alchemy? He gave a few instructions in a low voice, and the two servants immediately took action.

A long bamboo tube was brought in again, and a skin bag filled with clear water was attached to it for use, and another person scooped the wheat into the dustpan, ready to be lifted at any time.Cheng Jinzhou stood far behind the wheat pile, and told the others to stay away.

Sulfuric acid itself contains a large amount of dilution heat. To put it simply, it releases a large amount of heat when it is diluted.And because sulfuric acid is heavier than water, if water is poured into sulfuric acid, the water will float on the sulfuric acid. Only the contact surfaces between the two sides will generate heat, which will become localized heating, causing the liquid to tumble. A large amount of contact will cause more violent tumbling. Even if sulfuric acid is splashed out, if the amount is large enough, the operator will become like the Tsinghua version of the bear.

Therefore, the correct approach should be to slowly add sulfuric acid to the water, and keep stirring to make it fully dissipate heat.Due to its inherent danger, in the chemical experiment class at school, the teacher will inevitably give instructions and take the trouble to shout: "Pour sulfuric acid into the water, stir it with a glass rod..."

If sulfuric acid dilution had not been used too much in experiments and was unavoidable, the talents of the Ministry of Education would have found 10 reasons to ask middle school chemistry classes to stop such tragic and dangerous experiments.

Cheng Jinzhou didn't have the awareness of being a genius at all. Apart from shouting "Everyone back", he kept rubbing the rings in his hands, and whispered: "Mr. Ke, I said a deal, you just take the things."

"Okay." Customer service 010 had no objection to this.

Both Shen Cong and Lin Bo's eyes widened, ready to enjoy the performance of the Star Warlock who was immersed in sulfuric acid.

"Pour water." Cheng Jinzhou shouted.

One skin of water is quickly poured into the bamboo tube, flowing down the bamboo joints, followed by the second skin, and the third skin.

The concentration of sulfuric acid obtained by distillation and calcination is usually difficult to exceed 76%, but even if the quality is worse, the calories contained in 10 pounds of sulfuric acid are still quite terrifying.

The clear water in the first skin flowed into the sulfuric acid in a calm manner, making a squeaking sound, accompanied by faint white smoke. Shen Cong waited for three to five seconds, and was about to turn around to laugh when the water surface suddenly rolled over. After another two or three seconds, The entire stone tank became violent like water pouring into boiling oil, and splashed water droplets containing concentrated sulfuric acid in all directions.The servant who was pouring water from a high place hid behind the door panel with a puff, while the one holding the dustpan vigorously threw out the wheat grains, then hid his head behind the dustpan and ran backwards.

If it was just water in a skin, the performance might stop here, but the water stored in the bamboo tube is continuously poured into the sulfuric acid, and the water that has not fully reacted before is also accumulated together. The sulfuric acid flew up like an explosion. Whether it fell on the ground or hit the wall, the hot sulfuric acid would continue to emit heat, and the white gas with a burnt and spicy smell soon permeated the entire warehouse.

Cheng Jinzhou rubbed his ring face in a low voice and said, "Mr. Ke, it's a deal."

Piles of food quickly disappeared without a trace.

"Star Alliance Reader, "Elementary Mental Arithmetic Tutorial", there is a 50% surcharge for translation." Customer Service 010's voice was dry.

"Elementary Mental Arithmetic Tutorial?" Cheng Jinzhou read the name silently, and said decisively, "Sure."

12 words cost 120 stars, and an additional 50% will cost 180 stars, which is really not a small amount, but when Cheng Jinzhou sees the content on the command line, he will no longer think about the small problem of how much money he spent .

The door of the warehouse was wide open, and the warehouse that had dissipated the smoke smelled like the scene of barbecue dog feces. Shen Cong ran over coughing, and shouted with a miraculous face: "What was burned just now was food?"

The pile of grain, which was larger than a truck, was missing. The place was filled with thick smoke and the smell of burning sulfur. It was not surprising that he had such an association.

Cheng Jinzhou, who was planning to continue lying, didn't care about taking care of him. He rubbed his fingers and flipped through the pages of the book.The "Elementary Mental Arithmetic Tutorial" in front of him turned out to be a calculation technology that he had never even heard of. In the 21st century, there are already countless quick mental arithmetic methods, such as the famous abacus mental arithmetic. After systematic training, you can Completing the multiplication of 18 digits in one second is terrifying, but it is a calculation method after all, and it does not have the ability to analyze the problem. Users are more inclined to deal with numbers rather than other considerations. .

The "Elementary Mental Arithmetic Tutorial" displayed on the warning surface is obviously a calculation technique used to deal with practical problems.

"Star Alliance readings..." Cheng Jinzhou repeated what Customer Service 010 said earlier.

"What did you say?" Shen Cong asked Cheng Jinzhou with excitement and confusion.

"Do you know how many steps we have to walk from here to the lighthouse ahead, and then turn to the biggest ship on the right?" Cheng Jinzhou looked at the example in the void and smirked.

Most of the children of the aristocratic family know the basics of mathematics, Shen Cong asked without knowing why: "Can you calculate things with that acid?"

Cheng Jinzhou stretched out a thumb, pointed at the position of the carriage in front of him, and said, "Do you know how humans determined the latitude and longitude back then? It was through the projection of the stars and the sun."

With a mysterious expression on his face, he said to himself: "If I know the angle and the height, I will know everything."

"Who said this?"

"It's said in the book." Cheng Jinzhou laughed loudly and said, "Trigonometric functions plus rulers are used to make graphs. There is nothing else I can ask for."

……

(End of this chapter)