Lord, these are the lenses you want! Within a few days, Ma Jun brought a big cloth bag to Xiang Han's study.

After unfolding the cloth bag, Xiang Han saw lenses wrapped in cloth or paper.

"So much?" After seeing the lenses one by one, Xiang Han was a little surprised, he didn't think at all that in such a short time, Ma Jun could make so many lenses!

"Well, it's actually quite easy to make, as long as you master the knock on the door to make glass, you'll be fine!" Ma Jun smiled.

Xiang Han nodded, didn't say anything more, but picked up a convex lens, and then compared it to a line of small characters.

Under Ma Jun's surprised gaze, this line of small characters was directly enlarged!

"My lord, this ...... Is this called a magnifying glass? Ma Jun asked in surprise.

"Well, yes, you can go and make a wooden frame and make a handle, like this!" As he spoke, Xiang Han drew a magnifying glass on the paper for Ma Jun.

"So it can be like this!" Ma Jun suddenly nodded hurriedly.

"Also, you can design a cylinder like this, and then two convex lenses, and put them like this, and you can form a telescope! Of course, how this curvature is, you have to experiment yourself. Xiang Han simply drew a simple drawing of the telescope on paper.

"Lord, why is this thing magnified?" Ma Jun asked puzzled.

"Look at this, then!" As he spoke, Xiang Han picked up a concave lens again and put it in front of the line.

"Huh? It's getting smaller! Ma Jun was even more surprised!

"Actually, it's a refraction of light!" Xiang Han said succinctly.

"Refraction?" Ma Jun was very puzzled by this fresh term, and looked at Xiang Han curiously.

"Yes, it is refraction, in short, when light is obliquely emitted from one transparent medium into another transparent medium, the direction of propagation will generally change, this phenomenon is called the refraction of light, roughly draw a picture, that's ......" said, Xiang Han told Ma Jun all the little knowledge he had about light.

"I see! So magical! Ma Jun was surprised and praised repeatedly.

"In fact, there are many examples of this in life, like a chopstick, stuck in the water, do you feel that it has become bent?" Xiang Han asked with a slight smile.

"Huh? It seems like this! Ma Jun recalled.

"Also, when fishing, the fish swim in the clear water, and you can see it clearly. However, if you fork the fish in the direction you see it, you won't be able to fork it. Yes and no? Xiang Han asked with a slight smile.

"Uh-huh! That's it! Experienced fishermen will plug it cheaper, so that they can plug it! Ma Jun nodded.

"There are many such phenomena in ordinary life, as long as you observe carefully, you will definitely find them!" Xiang Han smiled slightly.

"Uh-huh!" Ma Jun nodded.

"Okay, you go and make this telescope, you also understand the specific refraction principle, I think you should be able to make it soon!" Xiang Han smiled slightly.

"Hmm!" Ma Jun nodded, but he had no intention of leaving.

"Anything else?" Xiang Han asked with some curiosity.

"Lord, that's the case, I still have some questions, I don't know if the lord can solve the doubts." Ma Jun said.

"Oh? Tell me about it! Xiang Han raised his eyebrows and said with a slight smile.

"That's right, I didn't notice it before, but recently I noticed a problem, that is, when the kettle is boiling, after the water is boiling, there always seems to be a force to push the lid of the kettle up! Why is that? Ma Jun asked curiously.

Although Ma Jun's question was simple, but for Xiang Han, it was extremely shocking, what age is it now, Ma Jun actually noticed the existence of steam power! In this way, it is more than a thousand years earlier than those countries in the West!

"This question, I have to explain to you what water vapor is first......" Xiang Han started with water vapor, and talked about the conservation of energy, and other knowledge, and finally explained this problem!

"I see! Lord, you know so much! Ma Jun said with great admiration.

"Have you figured out how you can use this momentum?" Xiang Han smiled slightly.

"My lord, this power is really too useful, too many places can be used to replace manpower!" Ma Jun said.

"Well, go back and study it well, by the way, how is that little girl Huang Yueying?" Xiang Han asked.

"Lord, our craftsman workshop is a group of big men, what do you want to do with that little girl? It's inconvenient! Ma Jun said with a bitter face.

"Didn't you see the repeater she made?" Xiang Han asked.

"Repeater? What repeater? Ma Jun asked with some confusion.

"You didn't even look at it?" Xiang Han was a little speechless and shook his head, "That's it, you come with me!" ”

Xiang Han and Ma Jun came to the craftsman's workshop together and came to Huang Yueying's separate room.

"This ......" Seeing the delicate trap beasts on the table, Ma Jun's eyes widened in surprise.

"Brother Zimo, why are you here?" After seeing Xiang Han, Huang Yueying was obviously very happy.

"How has Yueying's repeater improved?" Xiang Han asked with a slight smile.

Hearing Xiang Han ask about this, Huang Yueying's face immediately collapsed: "Shuo'er has tried many methods, but it doesn't work, Brother Zimo, you give Shuo'er a little more time, just a little bit!" ”

"Hehe, I'm not in a hurry, you've encountered a bottleneck, why don't you discuss it with these masters outside?" Xiang Han smiled slightly.

"This ......" Huang Yueying's face turned slightly red.

"In this case, you take out the repeater first and show this Ma Jun!" Xiang Han smiled slightly.

"Hmm!" Huang Yueying nodded, and took the previous repeater and gave it to Ma Jun!

"This ...... It's so ingenious! Ma Jun sighed, and then whispered in doubt, "It doesn't seem right here, right?" ”

"Is there a problem here?" Huang Yueying asked curiously.

"Look, add a slot here......" Ma Jun put forward his own idea.

"That's right! That's it! Huang Yueying was very pleased and nodded hurriedly.

"Deheng, don't underestimate this little girl, his or her brain is better than yours!" Xiang Han smiled slightly.

"Uh-huh!" Now Ma Jun completely believed Xiang Han's words.

"In the future, if you two have any problems, discuss them first, and then come to me, I believe that you will benefit a lot from communicating with each other!" Xiang Han smiled slightly, and then left.

(End of chapter)