The microscope is not unique to advanced industrial society, and it was completely polished by hand at the beginning!

In 1590, two Dutch spectacle craftsmen and their father began experimenting with lenses. They put some lenses in a round tube, and an important discovery was born. Objects near the bottom of the tube are magnified and magnified much higher than the magnification of any single magnifying lens.

For the most part, their first microscope can be considered an innovation that could not yet be used as a scientific instrument because of the magnification of only 9x and the somewhat blurry images.

The world's first real microscope appeared in the late 17th century, and the inventor was the Dutch cloth merchant and the pioneer of the microscope, Leeuwenhoek.

He honed his own simple microscope with only one lens that he could hold in his hand for observation. By honing the fine in an innovative way, Leeuwenhoek achieved more than his contemporaries. He grinded a small glass ball into a lens, and the magnification reached 270 times. You know, other microscopes at that time had a maximum magnification of 50 times. He used this lens to build the world's first practical microscope.

At present, there is no shortage of craftsmen who can polish lenses in Li Zexuan's workshop, and Mo Lingwei herself will polish lenses, but the most difficult thing to do in a double-convex lens-type microscope is not the lens, but a series of fine adjustment devices.

At present, there are no machine tools in the workshop, and the screws used need to be polished and carved by hand, which is more time-consuming.

"Mountain Chief, I see what you mean! This microscope feels like it should be better than an astronomical telescope~! ”

A course on microscope principles and manufacturing processes lasted for nearly an hour, and the small blackboard was full of optical path diagrams and formulas, and then Mo Lingwei said excitedly.

Li Zexuan nodded slightly, and said, "Generally speaking, the microscope is simpler than the astronomical telescope, after all, Miss Mo, you are very experienced in polishing lenses now!" ”

When Mo Lingwei heard this, she immediately said with a sad face: "Mountain Chief, this polishing lens is very laborious, look at my hands, they used to be quite smooth, but now they are a little rough, how can I marry in the future~?" Why don't I call Xiao Ningzi to come over and help me polish my lenses~? ”

Looking at Mo Lingwei's white and flawless slender jade hands, Li Zexuan was quite speechless, where is this rough? Isn't it lying with your eyes open?

"Miss Mo, Shao Ning has been busy building a dam recently, where does he have time? But you're also talking about... It's not unreasonable, so let's do it, I'll let people make some skin-protecting babies in the future, how about sending you some when the time comes~? ”

In other words, the cucumber mask can not only apply to the face, but also to the hands, right~?

Li Zexuan thought silently in his heart.

When Mo Lingwei heard this, her eyes lit up, and now everyone has a consensus, that is, Li Zexuan's product must be a high-quality product, although she doesn't know what can protect her skin, but this does not prevent her from booking one with Li Zexuan first!

"Yes, yes! Mountain Chief! That's it! ”

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Walking out of the workshop quite speechlessly, Li Zexuan slandered in his heart, if Yan Shaoning marries Mo Lingwei home, it is estimated that the Yan family will be lively in the future!

This girl is lively and interesting, but sometimes it's very noisy~!

"Xianggong, Daddy has a letter~!"

Back at the Yunshan Courtyard, as soon as he entered the courtyard gate, Han Yuxi greeted him and said with a happy face.

"Oh~? What did the father-in-law say in the letter? How is he doing over there~? ”

Li Zexuan grabbed his daughter-in-law's thin waist and asked with a smile.

Han Yuxi didn't break free, so she gave up, she turned her head to look at Li Zexuan, and replied: "Daddy said that he bought three Zhuangzi over there, and he has dug the sewage treatment pond near the mine, and now it has been put into use!" He asked someone to buy a lot of curved ploughs from the workshop, and rented them for free to the people who did not have ploughs, and now the spring ploughing over there has begun for several days!

Daddy also asked the people to drink boiled water, saying that if they found out who drank raw water, whose rent would rise by half in the future, and now Daddy's Zhuangzi is the most favorite Zhuangzi in Yifang County to drink boiled water! The Wang County Order of Yifang County has praised it many times! Oh, Daddy also asked Xianggong in the letter, now that the sewage pool has been repaired and the water quality of the river next to Zhuangzi has also improved, what else should be done~? ”

Li Zexuan nodded slightly, it seems that Han Tianhu is over there and wants to move the previous development model of Hanjiazhuang over! After a moment of silence, he said:

"Now that we have a cesspool, the next step is to plant trees! If you plant trees next to the river, if there are more trees, not only will the water in the river become cleaner, but the air you breathe will also become fresher! ”

Lanzhou is rich in water sources, not only the Yellow River flows through the west of Lanzhou, but also small rivers such as Lanhe, Lanyi River and Weifen River in its territory, which are rich in water sources, which means that they can grow food, so the people in this basin live very happily, and it is precisely for this reason that the dynasties before the Song Dynasty, its political and economic centers are all in the north!

However, this land on the Loess Plateau, after the population expansion of the Sui and Tang dynasties and the war at the end of the Tang Dynasty, there will be very serious soil erosion, resulting in water pollution and even depletion.

The most direct and effective way to control soil erosion and water pollution is to plant trees, not only in Yifang County, Li Zexuan also wants to suggest that Li Er plant trees on a large scale in the waters near Chang'an.

Chang'an is now the world's largest super city, with a population of one million, and a population of more than two million at its peak.

Modern Xi'an has been "warm but not hot" in all provincial capitals in the country, a very important reason is because of the lack of water resources, yes, modern Xi'an is very short of water, the Tang Dynasty's "eight rivers around Chang'an", to the modern era after a water is gone. Without the Heihe Water Diversion Project, Xi'an does not know what would have happened.

If Datang wants to stand on top of the world forever, and if Chang'an City wants to continue to prosper and "expand", then the tree planting and shelter forest project must be carried out from now on!

Han Tianhu's letter gave birth to the idea of implementing Arbor Day in Datang in Li Zexuan's heart!

If the momentum is good, maybe it can really be! The main thing is to think about how to convince Li Er!

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