Zhou Nan learned from Gao Yun's letter that Yu Liyan was busy in Yanjing City to open a branch and recruit craftsmen, but unfortunately Gao Yun did not say it in detail. As for the progress of the state and county to distribute land to each household and recruit craftsmen, the two things of recruiting craftsmen and opening a department can be delayed a little, but the matter of dividing the fields cannot be delayed.

However, I believe that with Yu Liyan's sitting, with the assistance of Yu Zhongwen and other ministers, and most importantly, the support of the people, who would dare to stumble in this matter? Although the people are honest and simple, they naturally understand who is good to them. Besides, it is all the ownerless fields that are divided, and no one will jump out to stop them. In addition, the most attractive thing about the "Land Decree" is the new land that has been reclaimed, as long as it is reported to the government and the number of acres and location are registered, the government will not collect any rent within five years; It was only after five years that the normal collection of rent and tax began. Coupled with the extremely low rent, everyone is afraid that they will have less land to plant. At this time, if someone comes forward to block the "Land Decree", they will be setting themselves on fire.

I don't know if there are any inopportune aspects of the "Land Ordinance" and the "Decree on the Supervision of Prisoners", and I hope that Yu Liyan can make corrections as soon as possible.

Zhou Nan was thinking about it, but saw the grinder who polished the crystal and the craftsman who made the mask walked in together, and the grinder said to Zhou Nan, "Your mission is small, and the small one has been completed, please check it, is it agreeable?" As he spoke, he presented a round crystal stone with a thick middle and a thin perimeter.

Zhou Nan took it over, and saw that the polished crystal stone was crystal clear, the surface was flat and smooth, and the surrounding arc was regular and smooth, which was almost comparable to the glass lenses of later generations. It is hard to imagine that in ancient times, without high-precision machinery and equipment, such exquisite crystal objects could be ground only by hand, stones, cowhide grinding tools and other materials.

Zhou Nan held this crystal convex lens between the thumb and index finger of his right hand, looking towards the palm of his left hand, the palm pattern suddenly became larger and thicker, and the fingers also became thicker. Zhou Nan's magnification effect of this crystal convex lens is not strange, but there are some slight flocculent plaques in it, which affects the overall effect. However, judging from this crystal convex lens, it is still feasible to use crystal as a telescope.

Zhou Nan nodded, and first said affirmatively, "It's very well polished, but when you choose the crystal again, don't have this kind of tidbits in the chip, it's excellent." Saying that, Zhou Nan pointed out the flocculent plaque in the crystal convex lens to the grinder.

The grinder looked at it and said, "If you want to get rid of these flaws, you can't polish them according to the shape of the crystal stone, but you must choose a shape that has no flaws in it to polish, but I am afraid that the crystal stone will be used more." ”

"If it is not enough, I will ask His Majesty the Emperor for another visit. You just polish yours. Zhou Nan said indifferently. If it weren't for him, these crystals would just be sleeping in the emperor's treasury, and it would be better to use them.

"The little one knows. I just don't know how much of this kind of shackle your envoy will polish next? "The grinder is still called according to the old custom, saying that the convex lens is a sling.

Zhou Nan picked up a page of paper on the table and said to the grinder, "I have drawn two drawings here, and the size and size are indicated on them, and you polish two pieces of each according to the drawing." In addition, you will polish the crystal pieces that you have just polished, one thick and one thin, and polish two pieces each. ”

The miller took the pattern and was about to leave, but Zhou Nan stopped him again and said, "I see that you are accompanied by dust and fog every day, and you will have lung diseases over time." Since you are doing things for me, I specially ordered someone to make you a mask, and if you wear it, you will not be harmed by the dust and mist. ”

The craftsman who sewed the mask heard Zhou Nan talking about the mask, and hurriedly handed over the mask he had just sewn in his hand, and then he knew the intention of this Liao man to let him sew the mask.

Zhou Nan took the mask and put it on for the miller with his own hands, the grinder was so excited that he didn't know what to do, and only took off the mask after a while, and said gratefully, "In this small business, after reaching the prime of life, there are many diseases of coughing up phlegm and blood." The grace of your thoughts, the small toothless unforgettable, I don't know how long this thing can be used? ”

Zhou Nan said with a smile, "As long as you keep it clean, there is no deadline." However, this thing is easy to make, if you want to make it yourself, you can ask this master. ”

The miller glanced at the craftsman next to him and said, "When I return, I will show it to all my companions, so that they will all be blessed by the horses." I don't know when your envoy will use this sting? ”

Zhou Nan thought about the production time of the carriage and the time to make the barrel frame for the telescope, so he said, "I don't know if it will be polished in four days?" ”

"But with the dispatch of your envoy, the small one is to grind it overnight, and after four days, it will definitely be polished for your envoy!" This miller couldn't imagine that the Liao people he didn't know would carefully send someone to sew a mask for him to prevent dust, which is in the Wensi Academy, not to mention the envoy, even the supervisor and the conductor, no one cares about them, holding the mask specially made by Zhou Nan, naturally he has to do things wholeheartedly.

"Xiao Jiu'er, each person will be rewarded with ten taels of silver, let's do things." Zhou Nan asked Xiao Jiu to take out the silver, and each person was rewarded with ten taels of silver, and the grinders and the craftsmen who sewed the masks went back to work happily.

Zhou Nan himself sat in front of the table, there were a few pages of paper on the table, as well as pen and ink, Zhou Nan took the pen and began to draw carefully.

The simplest telescope, probably the principle Zhou Nan still understands, and he once took apart the broken telescope and looked at it. Therefore, what Zhou Nan wants to build is the kind of telescope that does not need a prism and only uses convex and concave lenses. If you use two convex lenses, you can magnify what you see, but what you see is upside down, unless you add a prism in the middle to refract a positive image.

The advantage of this kind of telescope is that it is simple to make, if you want to make a telescope with a prism, just arrange the tube structure of the telescope is enough for Zhou Nan to be busy.

In fact, Zhou Nan only roughly knows the principle of the telescope, which is composed of a concave lens and a convex lens, and even whether the objective lens is a concave lens or a convex lens, Zhou Nan doesn't remember. But it doesn't matter, when the lens is polished, he can try it. The diagram he just drew for the grinder also drew two kinds of thicknesses of the concave lens, one thick and the other thin, that is, after the grinding is made, compare it to see which lens can see farther.

Now he is going to draw a basic structural diagram first, and when he has two lenses, he will let the craftsman who has nothing to do to melt the gold collar and start casting the gold barrel - since it is made for the emperor, it is naturally super luxurious and exquisite, and when the time comes, give one to the emperor and keep one for himself.

Zhou Nan just drew a simple style drawing, as for how to install the crystal lens into it and fix it when the time comes, and adjust it back and forth without falling off, that is what these craftsmen have to do.

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