After cooling in the stone grooves, the next step is polishing.
First rub it back and forth with the same grooved grinding stone. The hardness of quartz glass is higher than that of ordinary glass, but it can't withstand Yarrow's strength. With the constant friction back and forth, the surface of the glass gradually becomes blurred and gray. But the power of convex mirrors is also becoming more and more precise.
After polishing the large convex mirror, and then the smaller one, both convex mirrors became gray, with some small scratches still vaguely visible on them.
Yaro changed materials and continued polishing.
Fine grinding discs, fine sand, semolina, pearl powder... Yaluo didn't have sandpaper to use, so he could only find these natural materials instead.
The fine sand is about forty meshes, the coarse flour is about eighty meshes, and the pearl powder has reached two hundred meshes... Yaro's movements gradually became more and more violent.
The mesh number originally refers to the fineness of the sandpaper, specifically the number of particles per square centimeter. The higher the mesh number, the more obvious the polished effect will be.
As long as you have patience and enough polishing material, a stone can be polished into a mirror that shines brightly.
When polishing, the mesh number can only be increased from small to large, and there should not even be too many gaps in between, otherwise it will be very laborious to polish.
Just like Foolish Old Man who moved mountains with a small spoon.
After grinding the single-digit mesh, use the thousand-digit and ten-thousand-digit mesh. The groove left in front is too deep. The sanding with the thousand-digit and ten-thousand-digit mesh can only grind to the surface of the tip of the groove, and it will be very difficult to polish. The difficulty.
Of course, two hundred shots were still not enough, so Yaro continued to change materials.
Linen can be polished to more than a thousand mesh, and it will feel "moist" after polishing.
A person's hand or wearing cotton gloves can see three thousand eyes. At this time, the lens is like some permanent objects. It can reflect the figure but it is difficult to see clearly.
Finally, there is wool felt, which was also used in the last polishing process of glass products in previous generations. The finished product can reach a level of 5,000 to 7,000 polishes.
"Finally done!"
Yaro shook his sore arm, looked at the two transparent lenses, and finally breathed a sigh of relief.
Pick up the mirror barrel made earlier, install the two lenses, and try to take a look.
"Huh? Why is it a little blurry?"
This is definitely not a problem with the lenses.
After all, Yaro had already checked the transparency of a single lens.
"Is the data given by the academy incorrect?"
Yaro tried to close the mirror barrel, but the more he closed the mirror barrel, the blurry his vision became.
This shows that the distance between the two lenses where the light rays intersect exceeds the length of the lens barrel.
“Is it because quartz glass has a lower refractive index?”
When the angle of incidence of light is fixed, the greater the refractive index, the smaller the angle of refraction.
From this point of view, it seems that ordinary glass is better. After all, the higher the refractive index, the shorter the distance between the mirror barrels required.
But you should know that the curvature of the lens can be adjusted. As long as the convexity is adjusted, the lens barrel can be made as large as you want.
The higher the refractive index, the more serious the dispersion will be and the lower the clarity will be.
Taking current lenses as an example, if the distance between the middle lens barrel is adjusted, first of all, the distance that can be seen will be much farther, and the clarity will be higher.
This is a good thing.
It’s not too difficult to adjust, just add a section to the mirror barrel.
It's just that the width of the mirror barrel and the convexity of the lens have been fixed for a long time. Even if one section is added, you can only see the farthest distance, unlike the original mirror barrel, which can be divided into three sections for viewing.
If you want to achieve the original effect without adjusting the lens power, you need to recalculate the width and length of the lens.
Or continue to debug and make modifications based on experience.
Yaro didn't remember the refractive index of quartz glass. It took a lot of effort to calculate it, not to mention that for now, as long as the telescope can see far enough, it is enough.
I tidied up the small yard a little and selected some materials and daily necessities to put into the space ring.
Yaro walked into the forest, and after making sure there was no one around, he used his magic power to activate the flying pendant. After reaching the extreme height of the flying pendant, he got into the console of the hang glider, controlled the hang glider, and headed towards the Perrin Manor. Fly in the direction.
The Perrin Territory is close to the mountains, and the surrounding terrain is uneven and full of valleys. Especially on the side close to the Perrin Territory, there are not only deep pits, but also two towering peaks that can be seen from Perrin Castle.
Due to the remoteness of the terrain and the steep roads, both peaks have no names.
Yarrow's goal is the shorter and closer mountain.
Looking at the mountain was a dead horse. Even though Yaro had already looked at the mountain peak in the castle, he could not estimate how big the mountain was due to the distance.
When Yaro circled around half a circle and landed on the mountain peak, he saw several towering "small trees" in memory, and when he looked back at the castle, but could only see a small black dot, he realized that this How far is the mountain?
"That's good. Such a long distance can also prevent the wizards who are following you from discovering your hiding place."
Among the tricks that Yaro exchanged, there was a wind spell that allowed people's eyes to see far away. The original name was just one word and could not be directly translated. Yaro called it 'Eagle Eye Technique' in comparison.
In fact, not only the wind system, but other systems also have many spells that can see far away, but Yaro made a choice and exchanged them all without wasting the contribution points.
"The exchange price of magic spells from a distance is not high, which may also mean that this kind of spells are highly circulated. Just hiding so far away is still not safe enough."
With this in mind, Yaro climbed up the tree, jumped towards the edge of the mountain, and stopped on the side in the direction of the castle.
"It should be almost done here."
This is the sunny side of the mountain, and the location Yaro chose is a corner of the rocks. As long as you step out of the cover of the rocks, you can have an unobstructed view of the castle.
Yaro set up a telescope in the corner of the rock and tried to take a look at the castle.
"The quartz telescope is really good. Although I still can't see everyone's face clearly, I can already vaguely see everyone's clothes. Based on these clothes, I can roughly tell who is who."
After confirming that the telescope was indeed effective, Yaro pulled some dry grass and vines from the ground, woven it into a fine net, and then shined it on the lens of the telescope to prevent the telescope from reflecting light and being noticed by others.
After getting these done, Yaro began to organize his residence.
He didn't plan to make it complicated, so he directly covered the glider in the cracks of the rocks, and then pressed the edge of the glider with stones.
Then the ground was cleaned, a trench was dug to divert rainwater, and a layer of sulfur powder was spread on the ground to get rid of mosquitoes.
After doing this, he took out all the grease accumulated in the castle in the past few months from the space ring.
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