As soon as the guard in the West Courtyard was lifted, the students knew that Master was coming out. Hurriedly put down the matter at hand and ran over to greet him.

When Zhao Hao walked out of the door, he saw Liuyang and Zhao lined up neatly, bowed down and shouted, "Master has worked hard." ”

Before the words fell, they turned the bamboo tubes in their hands one after another. In the thumping sound, the colored confetti sprayed out, and Zhao Hao was covered in head.

"Uh......" Zhao Hao was taken aback, and in an instant there was a feeling that he was shooting an earthy short video. couldn't help laughing and scolding: "Whose fucking idea is this?" ”

"Big brother!" Everyone pointed to Wang Wuyang.

Wang Wuyang hurriedly said with a smile: "The main reason is that I haven't seen my master for too long, so I want to make a simple ceremony to express my feelings in my heart." ”

Saying that, he hurriedly helped Zhao Hao take off the ribbon on his body.

"What is this?" Zhao Hao took the bamboo tube from his hand to take a look, and saw that it was very similar to the spray flower cannon at the wedding in later generations. But as far back as he recalls, the cannon was filled with compressed gas.

The eyes of the disciples turned to Zhao Shizhen again.

"This is the spray tube I made. Hollow out the joints of the bamboo tube, stuff the top with a roll of paper, and fill the bottom with gunpowder. The bottom can be turned, embedded with flint and fire steel, and the gunpowder is ignited in one turn. Zhao Shizhen sneered: "Bang, you can squirt out the paper roll inside." ”

"I'm not afraid to blow myself up!" Zhao Hao patted the back of his eldest nephew's head, but he was happy in his heart. After all, this kid's thinking already has the shadow of a flintlock pistol......

Sure enough, he was born an arms expert.

Zhao Hao secretly praised, threw the bamboo tube to the eldest disciple, and asked the disciples while walking towards the west courtyard, have you finished preparing for the exam?

The senior brother replied flatteringly: "Back to Master, according to your instructions, the disciples have focused on the big questions this month, and each of them has done a hundred articles, which can be said to be very well prepared. ”

The corners of Zhao Hao's mouth twitched when he heard this. Secretly, your ancestors only made one question, and they also consciously prepared well.

He has always felt a little sorry for the students, because of his own caution, he did not let them enjoy the happiness of 100% betting.

Therefore, before accompanying Zhao Erye in retreat, Zhao Hao had already made it clear that the chief examiner of this subject was Li Chunfang, a university scholar.

Li Chunfang is cautious as an official and cherishes his reputation very much, and such a character will definitely not rely on strange people to show his knowledge.

He is already the champion, the second-ranked bachelor, is there still a need to show off?

Therefore, it can be inferred from this that this examination is a big question, which should be very reasonable.

I hope that the disciples can waste less effort on the interception questions and make the already good results go further......

~~

After the master and apprentice had a reunion dinner, Zhao Hao went back to the house to stay for the exam.

At this time, even if you don't do anything and just sleep quietly, it's much better than chatting here.

The remaining three who don't take the exam will accompany the teacher to talk on the kang.

"How's that stuff going?" Zhao Hao asked without much hope.

At this time, he didn't hear a lot of banging explosions, if it weren't for the small danger factor of the Newco door machine, he would have asked Gao Wu to stop the experiment of the two.

Zhao Shizhen and Zhang Jian were already ashamed, so Zhao Hao's question, the two of them wilted directly. The latter was even more tearful.

"Master, we have failed to live up to your expectations, we have failed......"

"Oh, isn't it an old bomber?" Zhao Hao took a sip of tea, looking very understanding.

"Master guessed it right away." The two nodded like pecks of rice.

"Let's go, let's see." Zhao Hao got up and got off the kang, and the disciple hurriedly helped him put on warm boots.

When the master and apprentice came to the experimental room in the back courtyard, the first thing that caught Zhao Hao's eye was a model of a Newcomen machine made of bamboo and an iron kettle.

"Is this thing any good?" Zhao Hao asked with interest.

"This works well." Zhao Shizhen responded, quickly took a piece of homemade coal root the size of a moon cake, lit it and put it in a bowl to use as fuel. Don't forget to say to Zhao Hao with admiration on his face:

"Uncle's whimsical idea is indeed correct!"

"It's science." Zhao Hao corrected.

"Yes, a whimsy based on science." Don't look at Zhang Jian's lack of confidence, but his kung fu is very sufficient.

As he spoke, he filled the bamboo tube that served as a water tank with water. The water is sprayed into the cylinder made of bamboo and then poured into the iron kettle, which is tightly connected to the cylinder.

Then use coal root to heat the kettle. When it boils, the steam rushes onto the coarse bamboo, which is used as a cylinder. The increasing steam pushes the piston of the cylinder up, and the lever at the other end lowers its head.

When the piston rose to the top, Zhang Jian released the water again. Cold water is sprayed into the cylinder, the steam inside cools down and condenses, and falls back into the pot, forming a vacuum that sucks the piston down again, and the lever at the other end naturally rises again.

Then the steam is reheated and the piston is jacked; The water is cooled and the piston is retracted, and so on and so forth. In the steam filled, the lever was like a drilling rig in later generations, constantly looking up and nodding.

It can be seen that the two have thoroughly understood the simple principle of the Newco door machine, and perfectly restored the model, worthy of the name of genius.

After the model was successfully demonstrated, Zhao Hao turned his attention to the five or six cracked iron cans on the table.

"It's what we have the blacksmith cast." Zhao Shizhen said ashamedly: "I was going to compare the real automatic water lifter and make a ...... of the same material The proportional model comes out. But it didn't take long for the tin can to burst. Another one blew up as soon as it was used. ”

Zhao Hao nodded, picked up an iron can and looked at it, it had only been a few days, and it was already rusty......

He explained to the two: "It's a matter of material. Because the cylinder is integrated with the boiler, it expands synchronously with the boiler when heated. At this time, cold water is injected, and the inner layer of the cylinder will shrink rapidly. However, the outer wall is still in a state of expansion, and it will be subjected to the strong tension of the inner wall. However, the texture of the cylinder cast with pig iron is very hard, and the plasticity is extremely poor, so that if it is repeated dozens or hundreds of times, the uneven texture will be cracked. ”

"I heard that the guns of the officers and soldiers are easy to explode, is this the reason?" Zhao Shouzheng really deserved the name of the weapon master, and immediately thought of the idea.

"Yes, so to avoid blowing up the chamber, you have to use better materials, or change the way you make the barrel." Zhao Hao smiled, put down the tin can and said, "It's not your fault. I was lucky, and I thought I might be able to do it. ”

"Looks like we'll have to solve the material problem first." Saying that, he sighed lightly at himself, gave up the idea of ***, and said: "Let's put this matter aside for the time being, you still have to learn to lay a good foundation first, and then let's slowly figure out a way." ”

Seeing that Zhao Hao was about to leave the laboratory, Zhao Shizhen and Zhang Jian glanced at each other, and the former whispered: "Uncle, it's not that it's all for nothing. The sixth brother was inspired to build a pumping device......"

"Oh?" Zhao Hao couldn't help laughing: "Where is it?" ”

ps. The fourth update was delivered, 8600 votes plus more ~~~