In the early days of optics, the interpretation of color was particularly difficult. Before Newton, Aristotle's view of color was prevalent in Europeans. Aristotle believed that color is not an objective property of objects, but people's subjective feelings, and that the formation of all colors is the result of a proportional mixture of light and darkness, white and black.

In early 1666, Newton made a triangular glass prism and used it to study the color of light. To do this, he made the room pitched and made a small hole in the window to let in the right amount of daylight. He also placed a prism at the entrance of the light, so that the refracted light could hit the opposite wall, and through this experiment, he obtained a colored spot on the wall, and the color arrangement was red, orange, yellow, green, blue, indigo, and violet. Newton called this color spot the spectrum.

Later generations called this experiment the dispersion experiment of light!

In 1830, Thomas Young, a British physician and physicist, made a small hole in the shutter to let light pass through and reflected the light through it with a mirror. He then used a piece of paper about 1/30 inch thick to split the light into two in the middle. As a result, intersecting lights and shadows are seen.

This is known as Young's double-slit interference experiment, which shows that two rays of light can interfere with each other like waves. This experiment also played a crucial role in the creation of quantum science a century later.

Li Zexuan moved these two experiments to the Tang Dynasty to let the students of the academy understand that the sunlight they can see every day is not as simple as it seems! Light is a wonderful substance, and understanding its inner life will lead to a lot of amazing things!

At this moment, the curtains in the auditorium have been opened, but most people still haven't come back to their senses, they can't understand why there are only two beams of light, but they seem to have become many beams on the paper, how did Li Zexuan do it?

"Mountain Chief, what was ....... just now?"

A student couldn't help but stand up and wanted to seek the truth, but halfway through the question, he couldn't ask any more, because he felt that Li Zexuan would definitely prevaricate as before.

Sure enough, I saw Li Zexuan wave his hand and said, "Let's put this aside first, and I'll take you ......"

"Make a little game!"

Before the last few words could be spoken, all the teachers and students in the audience helped Li Zexuan speak out in unison, and the voice was so loud and angry, Li Zexuan on the podium felt a strong resentment coming to his face!

"Ahem! So you all know it! ”

Li Zexuan's forehead was sweating, and he said something embarrassed, and then he took out two iron boxes, and shouted to the side by the way: "Mo Zhong, Mo Yun, you two come here!" ”

The two brothers had already come down from the roof, and when they heard that Li Zexuan had something to do again, they had to run over again.

"You two hold a box, pay attention to the line in the middle, don't stay too far away from each other, otherwise I won't be able to spare you if the line is torn off!"

"Yes, yes, chief!"

The two brothers hurriedly agreed, and each took a box.

"Now you two go over there and stand!"

Li Zexuan pointed to the corner of the back of the auditorium and said.

The two brothers did as they were told.

Everyone is unknown, but there are two exceptions, that is, Li Tai and Cheng Chumo, because they have not only seen this thing before, but also played with it.

Li Zexuan took out two more iron boxes (one is a voltaic battery, and the other is a telegraph), and after the wires were connected, he raised his head and said: "The next little game is even more interesting, have you ever thought that one day, two people who are thousands of miles apart will be able to transmit messages to each other?" ”

Sun Zifan: "Send a letter!" ”

Wang Meng: "You can also fly pigeons to pass on books!" ”

Li Zexuan shook his head and said: "Thousands of miles away, how long does it take to send a letter and a flying pigeon?" These two things that you see today will be able to transmit messages thousands of miles apart in the future! ”

"Wow~!"

"This.... How is this possible? ”

"Thousands of miles apart, instantaneous transmission, isn't this a fairy method?"

Everyone in the audience was in an uproar again, saying that the number of times they were shocked today was more than in the past, and Li Zexuan was speechless every time!

"Due to the limited space, let's do a ten-zhang interval transmission experiment first! What kind of sound will the box on my side make next, and what kind of sound will it make in the hand of the ink clock! ”

Li Zexuan opened the tin box and began to send "telegrams".

"Didi! Drip~! Drip~! Drip~! ”

Two short and three long!

Almost at the same time, the iron box in Mo Zhong's hand also sounded "Didi!" Drip~! Drip~! Drop ~ "Two short and three long sounds."

The students and teachers felt amazing, but most of them didn't understand it very well.

"Mountain Chief, how do you transmit the news just like this drop of sound?"

A student asked, standing up.

"Hehe, that's a good question! This classmate, if you think about the sound you just heard, is there a long or a short? ”

The student pondered for a moment and replied, "Yes, Mountain Chief! ”

"Then think about it again, if I combine these long and short sounds with each other, and the different combinations correspond to one word, for example, I correspond to the word "Li" just now for two short and three long, then can I transmit the message through this? ”

As soon as the words fell, exclamations rang out!

"Wow, how could I not have thought of that? Mountain Chief's method is really amazing! ”

"I just don't know how far this thing can go!"

Li Zexuan said again at this time: "At present, according to my preliminary test, with this thing, we can communicate with each other within thirty miles!" If it is slightly improved in the future, it is not a dream to transmit news from thousands of miles away! ”

"Wow, more than thirty miles? That's amazing! ”

"Amazing! It's amazing! An iron box can send messages thousands of miles! ”

The auditorium was boiling again!

The older generation of college gentlemen all looked at each other in shock, and at this moment they really felt that they were old and couldn't keep up with the times!

"Okay, let's take this for now, there's still a lot to come! Mo Zhong and Mo Yun, please pack these things up! ”

Li Zexuan smiled again and commanded.

It is impossible for him to explain the principle of the telegraph in detail right now!

The students showed an expression of "sure enough", but now they are too lazy to complain, so they are silent and watch Li Zexuan's performance.

I saw Li Zexuan bring a basin of water from under the lectern, and then took out a box and two tubular glasses, then he looked at everyone and said with a smile: "The next moment is to witness the miracle, you will see the real creation out of nothing~!" ”

………………………

Pay off your previous debts and try to pay them off this month!

In addition, let's talk about rewarding and adding more, this chivalrous man has never officially said it before, today I specially said that the one-time reward of the alliance leader only adds five more, not because the chivalrous play a big name, the chivalrous really has no cards to play, mainly because the chivalrous is now at work, there is less free time, you just let me add twenty more I can't add it, it's really too tired after work every day, it's not easy to keep two more a day, the main thing is to hope that everyone keeps the book currency subscription, there is a subscription chivalrous is already very happy, don't ask for a reward!

Thank you for your companionship all the way, and thank you for your subscription, I wish you a happy day!

(End of chapter)