The conscience of heaven and earth is really not the first time that Li Su has been in this world for more than three months before paying attention to the mirror.

He also knew that the cliché method of making glass and mirrors to make money had long been used up by the time-traveling novels he had read in his previous life, and the huge profits of glass and mirrors had long been boasted about.

But as a liberal arts student, glass he really can't burn.

If you just increase the heat and burn the sand until it melts, you end up with something strange and smooth but cloudy—

He secretly took the time to do this experiment once when he was in Luoyang, and then gave up. At that time, Guan Yu almost thought that there was a fire in the place where he lived, but then Li Su finally prevaricated.

It was not until this moment, using the living utensils of the Mi family to entertain distinguished guests on the Mi Mansion that he suddenly opened his eyes: the clarity of the silver mirror of this world does not seem to be very bad, and it can still be used without glass.

It's a pity, and it's also strange that although Li Su has had business dealings with the Zhen family many times before, he has always dealt with the housekeepers and shopkeepers of the Zhen family, and he has never been invited by Zhen Yan to stay in the Zhen Mansion. So much so that it is only now that I have seen the top silver mirror of this era for the first time.

Otherwise, with the wealth of the Zhen family, most of the Zhen family can afford luxury goods.

After coaxing in her mind for a while, the maid of the Mi family had already wiped Li Su's hair thoroughly after washing, and then combed it with a comb while fanning her with a dough fan of silk noodles.

In the era when there was no hair dryer, it still took a lot of effort to wash your hair and dry it thoroughly. The weather at the end of April was already a little hot, and the maid fanned hard for 20 minutes, Li Su was cool and comfortable, and the girl was sweating profusely.

Li Su just thought about the big thing, and asked casually: "What's your name?" Do you know how much this silver mirror is worth? ”

The maid was slightly startled, and hurriedly tried to find a way to behave: "The slave and maid have no name, and the lady and lady all call me Cao'er." This silver mirror is made entirely of sterling silver...... It must cost dozens of copper coins, and if Childe wants to know the finer price, I will try to ask the steward. ”

Li Su listened to it and secretly thought: I really have a humble nickname, and I don't even deserve such a cheesy flower, so I can only make grass.

Silver was not in circulation in the Han Dynasty, but there was still some silver in stock, which was mainly used to make jewelry utensils.

Therefore, in fact, the exchange rate of copper and silver is slightly higher than the usual money in later generations.

The silver mirror in Li Su's hand is square and round (more than 22 centimeters in diameter), with a thickness of three points, and the back is also carved with moire birds and beasts, which is a very atmospheric high-end goods.

Converted into the volume of the afterlife, it is 20 cubic centimeters, and according to the density of silver, there are more than 200 grams. Li Su weighed and estimated the weight in his hand, and felt that it was about the same.

The value of silver itself is about five or six copper coins, but it costs dozens of dollars to make a silver mirror—at least according to more than 20 yuan, which is also four times the cost of materials.

In later generations, the processing fee for making gold and silver jewelry was definitely not so expensive.

Li Su couldn't help but be curious, and continued to ask: "Is the labor fee very expensive?" The carvings and inlays of these moire birds and beasts are extremely exquisite? ”

Li Su's aesthetic ability is not strong, and he can't see how valuable the pattern and gold craftsmanship of ancient handicrafts is.

Cao'er pointed to the mirror and said, "This slave knows a little - the cost and wear and tear of engraving on the back should not be too expensive, mainly because of this mirror." Even if the mirror is hidden in the most delicate silk sac, it will be black in a month or two, and it needs to be repolished.

The most expensive silver mirror is the grinding mirror, every time it is grinded, it should be at least half a point thinner, and the mirror in the son's hand will be used for a year at most, and it will be worn out - the slave maid also often sees the master silversmith in the house grinding the mirror for the ladies and ladies, so I know.

In this Donghai County, I heard that only a few wealthy families and dignitaries dare to use the same silver mirror as our Mi family, and the rest of the big families only dare to use the bronze mirror. The bronze mirror is still clear, but the portrait is gray and yellow, but the copper mirror turns green much slower than the silver mirror turns black. It is not distressing to wear out the loss, and a copper mirror can be used for several years. ”

Listening to Cao'er say this, Li Su suddenly realized that he had been deceived by so many years of time-traveling novels!

In fact, most of the contribution of glass to mirrors comes from antioxidant resistance, rather than clarity. The glass is kept out of the silver, isolating the air and preventing the silver from oxidizing and blackening.

And whether the mirror image is clear, has a fart relationship with the glass? Clarity is only related to the grinding process and the coarseness of the wear grain. As long as the grinding material is fine enough, the surface of the metal material can be mirror-reflected, which is very good - those stainless steel decoration pillars in the hotel lobby in the later generations can clearly reflect the figure, and the clarity is not much worse than the mirror.

Of course, unless you take a glass plate and silver chloride solution like the junior high school chemistry class experiment, and then do a silver mirror reaction to evenly precipitate the silver and plating it on the smooth glass, then you can make the precipitated silver surface as smooth as the glass surface. In this case, the glass does help with clarity slightly.

It can only be said that a group of liberal arts students wrote time-traveling novels, and they all said that "when they took out the glass mirror, they immediately leaked domineeringly, shook the tiger's body, and shocked the ancients to bow their heads", and as a result, they deceived Li Su for so many years.

Now, the problem has been split into two parts by Li Su:

First of all, the key to creating a clearer, less loss-making mirror is to come up with a better surface grinding technique – grinding determines clarity.

Secondly, to create a mirror that is more durable and does not blacken after grinding, this requires glass technology – glass determines durability.

In other words, the rich people in the ancients could actually use a relatively clear mirror, but they had to be used as consumables, and non-rich and noble families did not dare to play.

Li Su has never been able to solve the problem of glass, so it is better to throw it away.

Taking advantage of the fact that Mi Zhu has not come back and has been a guest at Mi's house for two days, it is better to secretly ponder how to improve the grinding technology of this era, and when the time comes, make an improved silver mirror that is "as clear as a glass mirror, but just not durable enough".

In this way, whether it is to sell it in the future, or to exchange this slightly improved version of the technology with Mi Zhu as a bargaining chip, there will be an extra spare tire.

In fact, it is not bad to exchange chips, because the improvement of this technology is not very large compared to the old product, but the quality is improved.

In the terminology of later patent law, this kind of micro-innovation is not at the level of "invention", but can only be regarded as "utility model".

This kind of improved thing is still expensive and expensive, and it needs to be played by big businessmen who have mastered the channels of the rich.

If Li Su does it alone, I am afraid that he will not be able to sell much if he grinds it out.

Cao'er saw him stunned and occasionally rubbed against the silver mirror, and felt strange, so she posted it and whispered with concern: "Son, what's wrong with you?" Want this mirror? As a son, if you really want it, the head of the family will definitely give it away. ”

Li Su came back to his senses slightly: "No, how can I be rare to see a mirror-but by the way, do you know how this mirror is polished?" Is there a silversmith in the house today who wants to sharpen the mirror? I was intrigued to see the silversmith in action. ”

Li Su also found that he couldn't think of any countermeasures after a few blind thoughts.

Although the slight improvement of the grinding process is much less difficult than making glass, it is not something that a liberal arts student in his previous life, who lacked technical imagination, could casually think of.

He probably hadn't even seen a ball mill in his previous life.

Cao'er heard him suddenly say that he wanted to see the mirror grinding, and he didn't know what to do for a while: "Slave go and inquire for the son, I don't seem to have heard that there is a mirror to be polished in the house today." ”

……

Li Su wandered around for a few days like this.

With the stories of "Xiaoyilu" and other literati legends in the past few days, more and more spread in this Qu County, the Mi family also knows Li Su's coffee position, and they are more and more courteous to the diet and daily life of this "celebrity official", but they can't see him because Mi Zhuzhen is not at home.

For Li Su who wants to go to the city to wander around and secretly observe the Mi family's industry by the way, as long as it does not involve trade secrets, the Mi family doesn't care about him, just look at it.

After a day, Li Su also roughly understood that the Mi family now really has a large merchant fleet and river and sea trade.

Qu County is equivalent to Lianyungang in later generations, the seaport conditions here are still good, there are rivers from here into the sea at the end of the Han Dynasty, the waterway trade is very developed, the Mijia is the richest man in a state, how can it not pay attention to the low freight water transport trade.

It's just that there seems to be no difference between the sea ships and the inland river ships in this era, Li Su went to the commercial port to observe a circle, and recognized that the merchant ships of the Mi family were the style of the Yellow Sea sand boats in the later generations, flat bottoms, common to the river and sea, nothing more than the sand boats of the Tang and Song dynasties, and smaller, but the appearance pattern is almost the same.

Of course, it is estimated that there is no watertight compartment - this is not something that Li Su can see, but he has read history roughly, and knows that the watertight compartment is estimated to appear in the Tang and Song dynasties.

Therefore, the Mi family's sand boat, that is, sailing close to the coastline, will not enter the far sea where you can't see the land.

After walking around the shops in the city and the wharf outside the city, I returned to the guest room in Mifu in the evening, where the maid Cao'er was already waiting.

Seeing Li Su coming back, the maidservant hurriedly came over to sell it: "Li Gongzi, good news - today I told Aunt Zhao who was in charge of us that you wanted to see the mirror grinding, and Aunt Zhao tactfully told Mrs. Miss, Miss was kind, saying that since there are distinguished guests who want to see it, I will invite a silversmith from the business to come to the house tomorrow to grind the mirror, which is not a big deal." I'll take my son to see it tomorrow. ”

When Li Su heard this, he was immediately a little embarrassed: "If you grind this more time, you will lose it one more time, since it is not so dark that you can't see it, why bother grinding it in advance." ”

Cao'er said proudly: "Miss said, since the guests in the house have this elegant taste and want to watch, don't slack off." Grinding the mirror one more time is just a few taels of silver, so why worry about it. ”

For a big tyrant like the Mi family, a few taels of silver can satisfy the guests, of course, they will not hesitate.

——

PS: I got up in the morning and looked at it.,Just the new book period ended.,So it's still updated as usual today.,And I don't compress the number of words.。 Next Wednesday Jiang, the smoothest situation will be on the shelves on the Friday of September 25th (to see if the follow-up competition is fierce and whether it can be scheduled for a strong push period), the details are not clear, it depends on the situation.

Therefore, next week, we will continue to violently ask for recommendation votes, comments, pursuits, and collections. If 1 yuan live powder has not yet been realized, I will ask for a handful in the end. At present, the number of live fans is 407 people, if you follow this final frame, it will be 18,000 words on the day of listing (the app shows 22,000 fans, this number is fake, generally divided by 50 times equals real people.) In the future, if the number of live fans exceeds 500 before the shelves are put on the shelves, and the list of web pages cannot be displayed, we can divide the number of APP fans by 50 approximate judgment. That is, the number of APP fans is 25,000 before the strong push, and the first day explosion is 21,000 words, 30,000 APP fans, 20,004 for the first explosion, 40,000 APP fans, 30,000 words for the first explosion, and so on),

In addition, I would like to emphasize the importance of chasing more. Because whether readers are chasing more is an important indicator to judge whether a book is worthy of being pushed to the shelves in the sprint stage. If everyone is fattened, it may cause the book to continue to wait for the shelves to be put on the shelves. If there are many people chasing more, everyone works together, and it may be on the shelves on September 25th.

Thank you very much.

In addition, in order to avoid a shortage of books when everyone is chasing, pull a new book of other insidious historical texts to cushion the field: "There is a Good Disciple in the Northern Song Dynasty" by the ancient predecessor Wu Lao Wolf. I won't comment much on Brother Wolf's book.,Don't dare to say anything else.,The protagonist must be an unscrupulous.、Shameless old thief.,Book friends who like Machiavelli's idea are probably interested (in fact, Brother Wolf is very old.,It's not my turn to promote.,When I was still in college in 08,I first read his "Great Song Dynasty" and came into contact with the new world of insidious.。 This time, while he was in retreat for half a year, no one noticed it when he just came back, so he came over and beeped)