Chapter 48 Traveling Through the Middle Ages: Chapter 48

Chapter 48 Traveling Through the Middle Ages: Chapter 48

Louisa immediately met with Maxim.

Maxim was not a member of the Brundor Court, and if there was no urgent matter, it was unlikely he would come to see Louisa—thinking of the recent task assigned to Maxim, Louisa first thought that the issue of removing bubbles from the glass had been resolved!

As she expected, Maxim arrived, beaming with excitement, bringing with him the latest produced sample, a cut glass pane. This glass pane was square, measuring about thirty to forty centimeters on each side, and Maxim had wrapped it in linen before bringing it into Truwa Palace.

Louisa laid the glass pane on the table, carefully inspecting the glass's interior. It wasn't entirely bubble-free, but they were barely noticeable at first glance. If the pane was of this quality, it would be more than sufficient for making silver mirrors. The only question was, what was the production yield?

Previously, regardless of cost, among the large number of glass panes produced, one could select panes of similar quality!

If the yield remained disappointingly low, it would be meaningless—not a matter of cost, or rather, cost was a minor concern, as long as the price was sufficiently high, it could still turn a profit.

The bigger issue was that even if Louisa wanted to make silver mirrors a luxury item, they were not the kind that were literally 'worth a fortune'. How many of those could be produced? Only marginally better than a one-off transaction. In her plan, there needed to be a steady flow of silver mirror sales to truly be a 'source of wealth'.

Moreover, only in this way could the prosperity of a city be driven… historically, Venice's rise wasn't solely due to its mercury glass mirrors, but cities like Venice were uncommon at the time. For a medium-sized city like Truwa, which was already quite prosperous, a glass mirror industry could propel it to new heights.

"How did you produce such flawless glass? What's the production yield?" Louisa asked happily after looking at it.

She had her suspicions; at least it wouldn't match the previous yield, otherwise Maxim wouldn't have come bearing good news.

Maxim, who was prepared, immediately replied, "It's the new glassmaker Marco who made the difference! He is really skilled at mixing glass liquid. After he understood how we originally prepared the raw materials, he immediately proposed two changes. One was to adjust the amount of arsenic; we always thought that the more arsenic the better, but he suggested using less."

Louisa, because of her concern for window glass and glass mirrors, had a complete understanding of glass production. So she knew that arsenic was a type of arsenic ore—naturally occurring arsenic ore includes red arsenic and white arsenic, with white arsenic being purer, basically considered 'arsenic trioxide'.

If arsenic trioxide is pure enough, it can be expressed chemically as As2O3. In other words, to use arsenic trioxide, its effective component is As2O3.

Louisa actually didn't know that arsenic trioxide and arsenic were As2O3, she only knew that arsenic trioxide was used in glass production, probably as a clarifier.

So, the summary in time-travel novels that 'sand + limestone = glass' is too simplistic! Not only does it not mention the type of sand (sand is used for silicon dioxide, not all sand is suitable), but it also doesn't mention that clarifiers and fluxes need to be added to the raw materials when melting glass.

Without these, it's not that you can't melt glass, but it would be 'twice the effort for half the result'. Time-consuming, labor-intensive, and costly, but the resulting glass would be of poor quality!

Louisa estimated that people usually use arsenic trioxide as one of the clarifiers, naively thinking that the more you add, the better (as long as it's not too much).

In fact, people didn't realize that arsenic trioxide needs to be just the right amount to avoid the clarifier gas becoming supersaturated and too much, unable to be expelled in a limited time, thus remaining in the glass after the temperature drops and the glass forms (Louisa didn't know this either). It's also because arsenic trioxide is actually not cheap, normally used sparingly, and the resulting glass often has too many tiny bubbles due to insufficient clarifier.

As for using too much causing too many bubbles, people really didn't have the conditions to discover that.

Moreover, the number of bubbles in glass is actually influenced by many factors, and the effect of a single factor in a 'chaotic system' is not so easy to observe clearly.

"Then there's the processing of raw materials. To get cleaner raw materials, we always wash the recycled broken glass, as well as white sand. Marco thinks we are too hasty, washing the raw materials is right, but not waiting for the raw materials to dry before melting, which would definitely lead to an increase in bubbles."

With Maxim's explanation, Louisa understood—some things are not obvious until someone points them out, but once pointed out, as a modern person who knows a little bit of everything, one can still think of something.

Louisa guessed that some bubbles might be water vapor bubbles. The moisture in the raw materials would generally be evaporated at the high temperatures of glass melting. But it certainly wouldn't be completely evaporated in the first wave, and once the glass melt appears, it would be difficult to evaporate again. In a better scenario, it would combine with the clarifier gas, and most of it would be expelled.

In a worse scenario, it might even exist in an ionic state at high temperatures. Although the chemical equation shows that this doesn't happen in the glass melting process, based on Louisa's experience of doing experiments in this life, many changes are just due to harsh conditions, not the main reaction. But at high temperatures, more or less, a little bit can happen.

That doesn't affect the overall situation, but it can make a reaction less than perfect.

"...We tried again, and indeed the bubbles were significantly reduced." Maxim's tone was full of admiration.

He himself was also a glassmaker by origin, and he could see the gap between himself and Marco. Not only did the raw materials need to be dry, but this might also be the experience passed down by the glassmakers of Nice. But the addition of arsenic trioxide, although it sounds simple, how much clarifier is too much, and how much is too little, can it be easily explained?

At this time, many raw materials were not as 'pure' as in later generations, and production conditions were not guaranteed to be 'standard' every time. So in the production process, a lot really depended on the experience of the craftsmen, making some adjustments according to the situation!

Marco came and made a judgment casually. In fact, without even looking at the final result, just this point alone was a very impressive performance—if he didn't have that ability, how could he dare to make such a quick and decisive judgment? Such confidence is built on countless successes.

"Is this the glass we got?" Louisa pointed to the square glass plate spread out and asked.

Maxim replied, "No, Louisa, the glass we get now is much better, but achieving such perfection is impossible. It's still Marco who personally operates and is responsible for stirring the glass liquid. He must have more experience than anyone else. In short, when he does it, there are fewer bubbles."

Although it is generally believed that stirring the glass liquid can help bubbles escape, in reality, excessive stirring and vibration can also lead to the generation of more bubbles. So the specific operation entirely depends on the craftsman's experience. In the same workshop in the Middle Ages, experienced and skilled craftsmen can produce qualified products with a high probability, while others are a different story.

"It seems there is still much room for improvement in the glass workshop," Louisa said, not in an angry tone, but literally.

Maxim paused for a moment. Although he knew Louisa was not angry and did not intend to blame anyone, he immediately said, "True, but the workshop also excels in some areas, and Mr. Marco has praised them. For example, the coal we use in the kiln, he said the quality is very good, with very little soot, which is beneficial for reducing bubbles."

Soot and other impurities mixed in the glass liquid will decompose and form small but numerous bubbles.

Of course, even if people don't know the connection between soot and bubbles, they can naturally assume that high-quality fuel is beneficial for improving glass quality. But still, in a chaotic system, it's hard to say exactly how much benefit it brings. And the workshop has to consider costs, so it may not always use the best coal.

"And the material pit, probably because we don't do much blown glassware, mainly producing glass plates. Often, a large amount of glass liquid is poured into the rolling machine's feeding port at once, which happens to be beneficial for reducing bubbles—repeatedly dipping the blowpipe into the material pit for glass liquid can also lead to an increase in bubbles."

"This is also what Mr. Marco said."

Louisa guessed that it might be due to disturbing the surface of the glass liquid in the material pit, causing surface gases to enter the glass liquid...

"I’m not blaming anyone, just sharing my thoughts... well, everyone is doing a good job... so what is the success rate of such quality glass plates?" Louisa comforted and then asked the question she had asked before and was most concerned about.

Maxim explained in detail, "If Mr. Marco personally adjusts the glass liquid, three or four out of ten batches can reach this quality. But if others do Mr. Marco's work, it's hard to say. However, the slightly lower quality ones are close, and you can't see much difference without careful inspection."

Louisa did not agree with this. She wanted to make luxury silver mirrors, which are luxury items! Ignoring flaws for the sake of output would undoubtedly damage her own style and artificially lower the threshold for others to imitate, which is unnecessary.

Of course, she was not surprised that Maxim thought this way. Maxim didn't know that she wanted the best glass plates to make glass mirrors. He probably thought that Louisa just didn't like the previously produced glass plates and felt that there should be better window glass—like many extravagant nobles, always striving for perfection, preferably something exclusive to her.

And if that was the purpose, the 'slightly inferior' glass plates in the workshop would indeed be sufficient.

"A 30% to 40% success rate?" Louisa murmured to herself and nodded, "That's not unacceptable. However, having only one craftsman capable of this is not very safe. Let's do this: assign a few more assistants to Mr. Marco, and as soon as one is trained, give Mr. Marco a large reward."

Although Marco is indeed highly skilled, with a deep understanding of bubbles in glass, and has significantly improved the quality of the workshop's glass in the Middle Ages. But constrained by the 'non-standard' raw materials in the Middle Ages, the number of bubbles in the produced glass is still often uncontrollable... a 30% to 40% success rate has already satisfied Louisa.

"Training assistants? That will probably cost a lot of money," Maxim thought for a moment and said.

In the Middle Ages, masters teaching apprentices were similar to ancient China, often withholding knowledge, which was very common.

After all, unless it's their own son, no one wants an extra competitor in the industry. Of course, this is ultimately to protect their own interests, so if the expected potential loss of interest is compensated at once, masters in the Middle Ages might be willing to teach everything.

"Money is not a problem. Isn't the profit of the glass workshop quite high? Just deduct it from the profits to be submitted," Louisa said lightly.

The glass workshop is nominally Count Balzac's industry, but in reality, it is controlled by her.

Originally, a certain proportion of the profits should be handed over to her, and she would then transfer it to the Count (she reasonably keeps her own share, which is also tacitly approved by Count Balzac), and the remaining profits are used for the maintenance and expansion of the workshop. She can make such arrangements without asking Count Balzac, which is a reflection of her control and the high level of mutual trust with the Count.

Also, the glass mirror industry, with its promising future, has already been registered with Count Balzac. Using this as a reason, the glass workshop handing over less profit, the Count certainly wouldn't mind.

If money is not a problem, then the rest is easy to handle. According to Louisa's instructions, the glass workshop specially set up a group, assigned a separate glass rolling machine, solely producing high-quality glass plates. And from the glass liquid provided to them, every step is done regardless of cost!

Moreover, the glass they produce is also the most strictly tested, and only the best can be delivered. As for the slightly inferior ones in the workshop, they are shipped out with other window glass. However, they are also the highest quality among the window glass, listed as first-class, sold at the highest price—even though this high price is not enough to cover costs, it at least recoups some losses.

To show her attention and to confirm that Maxim was not exaggerating, Louisa even personally went to the glass workshop in the workshop and watched the entire glass production process.

Seeing the glass plates coming out of the roller conveyor belt, she directly inspected them in the workshop, confirming that everything was as Maxim said, and then she completely relaxed.

After thinking about it, she instructed, "You can hire a few workers who used to make wide glass sheets. The current glass plates are already perfect, and they don’t need grinding like wide glass sheets, but polishing them would still greatly help improve the quality. And when it comes to polishing glass, they are the professionals."

In fact, compared to the large glass mirrors in history in the Middle Ages, which were made by flattening glass plates on iron beds using large metal rollers, Louisa's method of using relatively rotating rollers for rolling is much better—although both belong to the rolling method in glass manufacturing, the former uses flat rolling, while the latter uses roller-to-roller rolling, and the difference is significant.

Flat rolling, in its simplest form, often results in uneven thickness, similar to rolling out dough with a rolling pin, where the resulting sheet cannot be completely uniform in thickness.

Slight unevenness in dough is no big deal, but uneven thickness in glass sheets for mirrors is a serious problem!

First, the glass thickness impacts the image quality, leading to distorted reflections. Additionally, the reflective effect is also related to the thickness!

Mirror glass has always needed to be thin. In fact, in Louisa's past life, ordinary mirrors were never thicker than half a centimeter. Before modern times, like in the 17th century with Versailles' 'Hall of Mirrors,' even those rare 'giant mirrors' were kept under 6 millimeters thick!

In short, mirror thickness and uniformity are both critical. Inter-roller rolling allows for uniform thickness by adjusting roller spacing and thinner than flat rolling, which requires more effort—modern rolling machines set roller spacing at 5 millimeters.

This thickness balances reflection quality and production efficiency. After all, the raw materials and production conditions at this time are not as good as in later times. Pushing for thinner glass risks stress fractures, causing cracks that even annealing can't fully fix.

Even if it doesn't crack, thin glass of this era is hard to transport and could shatter from minor bumps or vibrations.

Flat rolling's repeated compression is tough on this era's glass, beyond just thickness issues. Large sheets often end up with internal flaws or break outright—historically, giant mirror production had a high rejection rate.

Records show that out of 400+ sheets, only three met standards, yielding mirrors just over a meter wide and two meters tall. Others were trimmed to 1-1.5 meters tall. Most were crushed and recycled.

Inter-roller rolling has rejections too, but at an acceptable rate. Even blown and cast glass of this era has rejections—it's unavoidable. If Louisa widened the roller spacing, rejections would decrease. But she prioritizes mirror quality over fewer rejections.

As for the efficiency and flatness of flat rolling not matching inter-roller rolling, that's a minor issue. After all, large flat glass mirrors are luxury items, so lower efficiency is not a big deal. Poorer flatness can also be remedied by subsequent grinding...

"Polishing? Are you making glass mirrors?" Suddenly, Marco, who had been silent all along, spoke up.

Compared to Maxim, a glassmaker who lacks the concept of flat glass mirrors, Marco, who has lived in the Republic of Nice, is much more familiar with flat glass mirrors. In Nice, if glassmakers were to produce flat glass, it was mostly not for window glass (they also mostly used crown glass for windows there), but for making mirrors!

Previously, the glass workshop mass-produced glass sheets specifically for the high-end window glass market. This actually 'misled' Marco, making him momentarily forget about flat glass mirrors. But now, Louisa's dissatisfaction with the already very flat glass sheets made him think of glass mirrors.

It's not impossible to be so meticulous in making window glass, but it's really unnecessary. The cost increases significantly, yet the visual appeal as window glass does not improve much... And window glass with such high costs has a very limited market. Unless Louisa, the owner of the glass workshop, is using it herself and completely indifferent to cost, there's really no need to pursue this.

And with the current momentum of setting up a dedicated production line, it doesn't seem like it's just for personal use.

"Hmm..." Louisa neither confirmed nor denied: "You're very clever, and seem to know a lot about glass mirrors."

What these best glass sheets will be used for in the future, once the Troyes glass mirrors are unveiled, cannot be kept secret. So Louisa didn't play any tricks at this time.

Facing Louisa seemed to make Marco very uncomfortable. He lowered his eyes and head, fidgeted with his hands and feet before saying: "Yes, I mean, madam, I'm from Nice. When glassmakers there are asked to produce high-quality flat glass, it's almost always orders from mirror workshops."

"However, some mirror workshops have their own glass furnaces and don't need to place external orders..."

Although what Marco said was not related to the production details of Nice glass mirrors, and was of no use to Louisa, Louisa did not interrupt him, but let him continue. Only when Marco's slow and almost non-existent 'emotional intelligence' finally played a little role, making him realize he had been talking a lot of nonsense to a noble lady, did he stop.

Marco indeed doesn't care about anything other than 'glass.' But after all, he is a human living in the secular world, so he can't be said to have no common sense at all. When he belatedly thought of Louisa's noble status, he immediately became nervous—this was different from his previous discomfort, which could only be attributed to his personality.

Any stranger speaking directly like that would make him uncomfortable.

Marco could think that if it weren't for various coincidences, he would never in his life have the chance to meet such a noble lady and speak to her face to face... There's no other meaning here, it's just the caution, admiration, and fear of commoners facing nobles in this era.

Louisa waited until Marco stopped speaking, then smiled and said: "What you said is very interesting, I've never been to Nice, and know nothing about it... Ah, do we still have one thing to do? Your reward, you've been a great help, you should be well rewarded!"

"No..." Marco instinctively said 'no,' then realizing he had negated a future countess, he quickly explained: "I mean, I mean I've already received the reward, it's from the workshop... Mr. Maxim is a very good workshop manager, the reward was given promptly."

"Right, that's what the workshop should give. For a craftsman like you with superb skills, who has solved a major problem for the workshop, it would be wrong for the workshop not to give a reward. Such a stingy workshop has no future, who would be willing to contribute to such a workshop? After all, doing well or poorly is the same." Louisa said matter-of-factly.

This is very simple management wisdom, and at this time it cannot be said to be a secret. However, due to the nobility's disdain for commoners, and the stereotype of underestimating women's intelligence, it seems a bit incongruous coming from a female noble like Louisa, rather than from a seasoned businessman.

Louisa continued: "You've solved a big problem for me, not just for the workshop, so I must reward you. Don't refuse, everyone who works for me, if they do well, gets a reward... You can't make me lose credibility in front of my subordinates."

Of course, there are also punishments for those who don't perform well, but that's not necessary to mention, as Marco is not one of those around Louisa. To be precise, he is a technical talent. For technical talents, unless it's subjective malice, Louisa would not punish someone for not achieving something.

After pondering for a moment, Louisa nodded, "How should I reward you? If it's material wealth, the workshop has already provided you with that. And according to Mr. Maxim, you are not a man with much desire for wealth. I heard your wife has passed away, so perhaps I could introduce you to a capable lady as a wife?"

"No, that's not enough," Louisa herself dismissed the idea first. Arranged marriages might not have been popular in her previous life, but in this era, introducing a suitable marriage partner to a man was definitely a good thing. Especially for a man who has lost his wife and has children, without a wife, most of them would live in chaos!

"Your eldest son seems to have no intention of inheriting your career?" Louisa indeed valued Marco and had specifically inquired about this from Maxim. In fact, Marco's eldest son is already 14 years old. If he really intended to 'follow in his father's footsteps,' he should have been apprenticing under Marco by now.

"That child..." Marco muttered, "I don't know what that child is thinking. It seems he wants to be a dyer. Oh, his maternal grandfather was a dyer. When we were in Nice, we lived in a community of textile artisans, which might have greatly influenced him."

"That's not a problem," Louisa said gently. "Everyone has different interests and talents. I mean, if you are willing, I can sponsor and cultivate your eldest son. Within Brundo, Provan is a famous center for the weaving and dyeing industry. I can arrange for him to study there, apprenticing under the best dyeing masters. During his apprenticeship, all expenses will be covered by me."