Chapter 49: Journey Through the Middle Ages 049

Chapter 49: Journey Through the Middle Ages 049

The raw materials needed for making silver mirrors, apart from glass panels, are all produced in several small estates and castles owned by Count Balzac.

First, there are nitric acid and hydrochloric acid. Nitric acid is required for making silver nitrate, while hydrochloric acid is needed for hydrolyzing starch to obtain a glucose solution.

While laboratory production was inefficient, considering they were used for luxury goods such as silver mirrors, it was acceptable. However, nitric acid did not need to be produced by the mirror workshop itself, as it was available for purchase.

Generally, goldsmiths used nitric acid to purify gold. Specifically, in gold-silver alloys, nitric acid could dissolve the silver, leaving behind the gold. In fact, these 'strong acids' were mostly related to gold at this time. Sulfuric acid was mainly used in gold purification through the cementation method.

In short, though specialized, nitric acid could indeed be sourced. As for whether this would expose the silver mirror reaction formula, it actually wouldn't. If one were to be concerned, purchasing the raw materials for making nitric acid would also expose the formula.

With so many things being purchased, nitric acid had its own uses, and with the intelligence capabilities of the time, it was really difficult to uncover the details this way. In comparison, directly bribing the mirror craftsmen was more likely... hence the need to scatter the raw material sources, so that those producing the materials might not even know they were related to glass mirrors.

Additionally, the mirror craftsmen received raw materials from different sources, and many didn't know what they were using.

Hydrochloric acid was more troublesome than nitric acid. At this time, there was no method for extracting hydrochloric acid, so Louisa had to devise a new method. Fortunately, Louisa knew the chemical equation and had an idea of which raw materials might work. Combined with Helena's foundational alchemy knowledge from this era, they eventually succeeded.

In fact, the method for producing hydrochloric acid was very similar to the process for producing sulfuric acid at the time, just using different raw materials... It was Helena who, based on experience, chose a method similar to that used for other strong acids, which allowed them to resolve this issue quickly.

It wasn't strictly necessary to use hydrochloric acid to hydrolyze starch to obtain glucose, but when Louisa tried using other acids, even when successful, the results were not good. Finally, she had to bite the bullet and work on hydrochloric acid—essentially, among the common 'acids' in Louisa's memory, she had tried almost all of them, and only hydrochloric acid remained, which turned out to be the best.

Dilute nitric acid, and silver powder, are mixed in a certain ratio and heated, allowing the silver powder to completely dissolve the silver. This yields a silver nitrate solution and releases nitrogen monoxide gas. If heating continues, the solution can be concentrated into a supersaturated silver nitrate solution, which, upon natural cooling, will precipitate silver nitrate crystals.

If Louisa were to produce silver nitrate in the mirror workshop, there would be no need to precipitate silver nitrate crystals; stopping the heating once the solution reaches the required concentration would suffice... since the solution would still be needed for the silver mirror reaction.

Of course, with the raw materials produced elsewhere and not nearby (by the standards of the time), it was better to precipitate silver nitrate crystals. Convenience of transport was one aspect, but consideration also had to be given to evaporation during transport, which could cause the concentration to differ from that initially produced... these things needed to be accurate, or there would be losses later.

With silver nitrate, producing a silver ammonia solution only required ammonia water. This also did not need to be made by Louisa and her team, as ammonia production was already industrial at this time, much more common than nitric acid production—people obtained concentrated ammonia from aged urine, mainly used as a more efficient cleaner than urine for removing grease from clothes (although from Louisa's perspective, she preferred grease over the smell of ammonia).

Additionally, ammonia was used in producing alum and making pigments, but these were fringe applications of ammonia at the time.

Then there was just sodium hydroxide solution and glucose solution, the former easily made from quicklime and could be prepared on the spot, while the latter was much more complex.

In a small estate, peas grown on the estate were used to obtain pea starch through washing and sedimentation. Only then could the hydrochloric acid sent from elsewhere be used to hydrolyze the starch to obtain a glucose solution.

After hydrolysis, some soda ash (sodium carbonate) had to be added—hydrolysis is just starch and water decomposing into glucose, with hydrochloric acid as a catalyst not participating in the reaction. So after hydrolysis, alkali had to be added for neutralization.

Sodium carbonate was a good choice for neutralizing hydrochloric acid; it was not too strong and would not cause glucose denaturation. Additionally, it was readily available at this time, as natural soda ash was not rare.

Also for the convenience of transport, to avoid changes in the solution during transport, these glucose solutions had to be crystallized. For crystallization, sufficiently pure salt had to be added to the glucose solution, because sodium chloride and sugar could co-crystallize (using salt as a nucleus for glucose crystallization, adding salt would speed up crystallization).

The precipitated co-crystals were mixed with a small amount of water and re-crystallized in a low-temperature environment (theoretically, temperatures around 20°C would suffice, but for smooth crystallization, it was done in an ice bucket). This way, only glucose would crystallize, and the salt would remain.

Later, Louisa thought about why hydrochloric acid worked better than other acids in hydrolyzing starch and concluded that it might be because the neutralization products of hydrochloric acid were all resolved in subsequent treatments: the reaction products were just sodium chloride, carbon dioxide, and water, with carbon dioxide automatically escaping, water evaporating, and sodium chloride functioning together with the later added salt in co-crystallization.

The relatively complex co-crystallization method for purifying glucose was initially just Louisa trying every possible method, and later it turned out to be one of the few successful methods, producing the purest glucose...

Thus, there was finally a chance to produce relatively pure 'glucose'... honestly, the most easily obtained glucose in later generations was the most complex and had the highest failure rate in the entire process, significantly increasing costs.

In any case, even if every part had the potential to fail, as long as cost was not a concern, there would always be qualified output—this was the reality. Under Louisa's prior arrangements, the 'production teams' established in various locations had already accumulated a batch of raw materials for the silver mirror reaction by the time the glass workshop overcame the bubble problem.

Thus, in a secret manor house in the outskirts of Troyes, Louisa witnessed the first official mirror-making—the silver mirror she had shown to Count Balzac earlier was actually a laboratory product. It was made by her and Helena in a laboratory set up in Troyes Castle, not in the mirror workshop.

Of course, making it in the mirror workshop wouldn't have made any difference.

Silver nitrate mixed with water to form a silver nitrate solution, which was then mixed with diluted ammonia water to obtain a freshly prepared silver ammonia solution (silver ammonia solution could only be prepared fresh). Then, only a small amount of sodium hydroxide solution was needed in proportion—the glucose solution was not added immediately because the reaction would start once it was added.

"Proceed," Louisa ordered, seeing that the craftsmen had already mixed the three solutions and placed the glass panel, under everyone's anticipation.

The placement of the glass plate was specially arranged, resembling a frame structure made from glass. As for the glass plate, placing it inside was equivalent to the backboard of the frame—during the silver mirror reaction, the solution mixed from silver ammonia solution, glucose solution, and sodium hydroxide solution would be poured onto it.

After Louisa gave the go-ahead, the craftsman first applied melted beeswax to the seam between the bottom of the 'frame' and the glass plate. Although the glass plate was pressed against the frame, preventing much of the solution from seeping out, it was still necessary to take precautions.

After applying the beeswax, a lead craftsman added the glucose solution to the pre-mixed 'three-in-one' solution—the container holding the solution was suspended above the glass plate. The craftsman, based on prior trial experience, shook the container before pouring it onto the glass plate.

Louisa recalled from her past life that the textbook's silver mirror reaction required the test tube to be placed in hot water for a water bath. Now, this step was unnecessary, thanks to her chemistry teacher from that time, who, for the sake of 'fun,' did not have the students use test tubes but instead used glass plates. The goal was to create an actual mirror to take home, ensuring a memorable experience.

Louisa certainly remembered it well.

Naturally, a glass plate wasn't suitable for a water bath, so the teacher taught them to make the sodium hydroxide solution more concentrated. This way, the silver mirror reaction could be completed quickly at room temperature without the need for a water bath.

This was indeed the case. About 2 to 3 minutes later, an apprentice who had been crouching and closely watching the bottom of the glass plate stood up excitedly: "The mirror! The mirror is done... the silver plating is successful!"

Yes, the essence of the silver mirror reaction was simply a 'silver plating'... It was counterintuitive, but silver plating was a very late development. If sticking silver powder or applying silver foil didn't count as silver plating, then at least for now, there was no silver plating technology. In contrast, gold plating was an ancient craft.

As the silver mirror reaction completed, a shiny silver layer was formed. After a short wait, until the apprentice crouching under the glass plate confirmed that the silver layer on the back of the glass plate was very complete, with no unplated areas, the craftsmen proceeded to pour out the waste liquid from the 'frame.'

After that, they did not immediately clean the residual waste liquid on the surface of the silver layer but left it aside to dry. The mirror workshop manager explained to Louisa: "Well, as you can see, Lady Louisa, we still have to wait a bit. The silver layer just plated is very fragile, and cleaning it now could easily damage the silver layer."

Louisa, naturally, knew this, as the current production process was one she and Helena had tested in the lab. However, the guy currently running the mirror workshop clearly didn't know this and only knew that the mirror-making technology came from Louisa—he, in line with the era's mindset, didn't believe Louisa had developed the technology herself but assumed she had capable people around her.

So, it made sense for Louisa to need an explanation of the operational details.

This mirror workshop manager wasn't actually one of Louisa's people. Count Balzac, who valued glass mirrors, had sent his own man after the workshop was established... This somewhat had the air of taking credit, but Louisa remained calm.

This was because, on one hand, Count Balzac allowed her to send her own people as assistants to the manager, both to supervise him and to ensure that Louisa could directly and consistently receive her share of the profits from the glass mirrors. On the other hand, this manager was quite savvy and respected Louisa's authority in the workshop.

Louisa didn't mention knowing, as the silver mirror reaction was not her academic achievement (although she had put in great effort to replicate it in this era), so she naturally had no motivation or confidence to 'claim credit.' She didn't bother explaining that others didn't believe the technology came from her... To those in the know, this was seen as her modesty.

She was more concerned with the mirror that was drying and asked, "What is the size of this mirror?"

The manager, who had clearly memorized every aspect of his job in a very short time, immediately replied, "This mirror is 7 feet 1 inch by 4 feet in size."

Louisa mentally converted this to about 2.4 meters by 1.2 meters, which was truly a 'giant mirror' by the standards of the time!

The manager, without waiting for Louisa to continue questioning, added, "As per your instructions, we have also prepared other frame devices that can be used to make several other sizes of mirrors, including even round mirrors. But the largest is this size. This is truly unheard of; even metal mirrors from the past should not have been this large."

"However, this is indeed a genius idea!" The manager did not forget to flatter Louisa: "I heard from Madam Hugo by your side that you plan to name such a large mirror a 'dressing mirror'... Yes, having such a huge mirror while dressing would be incredibly convenient."

"And, in a luxurious and beautiful room, having such a crystal-clear, shining mirror would be truly astonishing! Enough to leave everyone who sees it in awe and amazement."

This was also very important, as the nobility of this era placed unprecedented emphasis on 'face.' They loved to display their wealth, grace, and transcendence through lavish scenes, grand displays, and generous rewards.

To the other party's flattery, Louisa neither agreed nor disagreed, merely curling the corner of her mouth and saying, "Sounds good... Be careful, these are glass plates that have been carefully selected and polished with the finest powder, requiring a lot of work. If something goes wrong here, all the previous work would be wasted."

Such a large glass plate, and so thin, was undoubtedly very fragile (given the quality of glass at the time, this was certain), so Louisa's concern was not unwarranted. In fact, the glass mirror could have been made even larger, but the reason it wasn't was that larger sizes would be even more prone to breaking... Of course, it was also unnecessary, unless Louisa intended to create a spectacle, decorating an entire wall with a single, complete glass mirror.

In her previous life, the Hall of Mirrors in history didn't even do that... The Hall of Mirrors used glass mirrors to form the shape of arched glass windows opposite, with a 'glass mirror window' composed of 21 mirrors.

"By the way, are there enough goldsmiths?" Louisa thought of something and asked.

The manager of the mirror workshop nodded repeatedly: "This is easy to handle, as long as there is money, it's already done! The most famous goldsmiths in Troyes are willing to take on this job. If we had more time, goldsmiths from Provins, Cité, and even Roland could be invited to work in Troyes."

Goldsmiths were responsible for making the mirror frames. Just as clothes make the man and the saddle makes the horse, a good mirror also needs a good frame to complement it. Since these glass mirrors were to be sold as top-tier luxury items, their frames naturally had to be made of good materials and craftsmanship. Silver, gold-plated, with intricate and beautiful carvings as the basics, and further adorned with jewels, ivory, etc., to create truly 'treasure mirrors'!

And this type of work was done by goldsmiths at the time—the reason Louisa didn't hire a few goldsmiths exclusively for the mirror workshop was also a consideration.

She thought that different goldsmiths had different styles, so the frames made would rarely be repeated, each being a unique piece of art... The top echelon of the pyramid at this time pursued novelty, not just following others' 'innovations' but also loving to create some innovative operations themselves.

They probably wouldn't want the mirror they spent a fortune on to look too much like someone else's.

This also better justifies positioning glass mirrors as top-tier luxury items... Louisa may be in the luxury business, but she’s no scammer! The core advantage is multifaceted, unlike in the future where it might just be about a logo.

Louisa, satisfied with the answers, didn't ask any more questions. By the time the next mirror started production, the previous one had dried somewhat. She didn’t stick around to watch as the leftover waste liquid was rinsed off with clean water and a thick coat of paint was applied outside the silver layer to protect it—right now, the bottleneck in the mirror workshop’s production is the limited supply of raw materials.

The glass panels, polished to a gleaming shine with polishing powder, and the chemical ingredients needed to make several solutions, are not easy to supply. In contrast, the silver mirror reaction is surprisingly fast.

It’s not that they can’t ramp up production of raw materials, but the problem is, that would result in too many silver mirrors being produced! It would be tough to keep up the luxury brand’s image—Louisa had initially planned for silver mirrors to boost Troyes’ economy, but she's not sure if that plan has failed or succeeded.

If it’s a success, limiting production capacity means fewer citizens benefit than expected, and the ripple effects are not obvious. If it’s a failure, the industry still employs quite a few people.

Besides the mirror workshop’s direct employees, even the glass workshop has opened a new team specifically to produce the highest quality glass panels. This master, along with apprentices and helpers, makes up about ten people. Polishing, the most labor-intensive part, employs dozens of people! After all, it takes several days for two people to polish a qualified glass panel to perfection.

Next, the chemicals used to make the solutions, whether produced in Louisa's own small workshops or purchased from the market, provide decent-paying jobs for quite a few people—conservatively, about a hundred!

All in all, about two hundred people are employed, and considering that Louisa has provided them with good compensation, each person can support a family... this actually means that two hundred families are living a decent life.

Even at a lower estimate of four people per household (in ancient agricultural societies, whether in China or the West, under normal circumstances, the average family size was between four to five people), this amounts to 800 people.

What does this mean? At this time, some small cities have only two to three hundred families, with a total population of about a thousand people. Such cities, population-wise, aren’t much bigger than some thriving villages with a hundred households. It's just that the population density is higher, with more people engaged in handicrafts rather than agriculture.

So, if Louisa were to centralize the entire silver mirror industry, it would be enough to establish a small town on the spot—200 households engaged in mirror-related industries, plus some households working as builders, carpenters, metal craftsmen, etc., serving those 200 households, would make up a small town with a total population of over 1,000 people.

But Troyes is a big city at this time, with about 5,000 families and a population of twenty to thirty thousand. With such a scale of the mirror industry integrated into it, the impact is not as significant—but even so, it still directly affects the livelihood of 1/25 of the city's families (not even counting the indirect benefits), which cannot be taken lightly.

It's just that, not being centralized, much of it doesn't show. Especially since a large part is kept away from the city for confidentiality reasons (including the mirror workshop itself, which is located in the suburbs), it doesn't contribute much to the city's development.

However, Louisa doesn't care much about these things. As a medieval lord, being obsessed with 'urbanization' would be too foolish.

Louisa left the mirror workshop after announcing double wages for the week, and even apprentices without wages would receive a reward equivalent to a week's pay of a regular employee—Louisa doesn’t know much about management, after all, in her previous life she was just an ordinary college student with zero social experience.

But having lived in modern times, she at least knows a bit of everything. She knows that as a feudal (preparatory) 'lord', as long as every act of grace is not blocked by the middle layer, and the people below always know whose rice they are eating and whose rewards they are receiving, and as long as no principled mistakes are made in other aspects, it's basically stable.

After leaving the mirror workshop, Louisa didn't put the glass mirror matter out of her mind, but rather kept it more in her heart. She clearly understands that this source of wealth is only halfway done at this point, and the other half is promoting the glass mirrors.

Even though glass silver mirrors are very impressive in this era, without promotion, just taking them directly to the courts of the great nobles, their extraordinariness is self-evident, and people are always willing to pay a high price for them. But promotion can't be completely neglected—Louisa, with her modern pace, isn't willing to wait for the trend of glass mirrors to slowly form.

For people of this time, it's already fast for a luxury item to spread and become popular in various courts over a few years, but Louisa can't wait three to five years.

Moreover, promotion always has its significance. It might not be possible to sell a product worth 100 units for 10,000 units, but there is hope to sell a product worth 1,000 units for 10,000 units.

"...Has anything big happened recently? I mean, the kind of news that everyone is concerned about!" Louisa was thinking about how to make a stunning debut for the glass silver mirrors, the first appearance must leave as many people as possible with a deep impression. But she couldn't think of a good opportunity for a while, so she asked her maids and attendants about the latest news.

Of course, when it comes to news, with the speed of news dissemination at this time, the timeliness is just so-so. What's being talked about now might have already passed.