Bohemian Cement (4)
Two months passed as swiftly as an arrow in flight.
The October autumn breeze was already pervasive throughout Prague.
In years past, the city, having been swept by the autumn rains, would have been a slushy mess of filth-ridden mud.
Carriages stuck fast in the mire.
Hemlines soaked in muddy water, reduced to rags.
And the foul, pervasive stench that seeped deep into the city’s lungs.
It was the inevitable landscape of Prague that arrived with this season.
But this year was different.
The central boulevard, stretching straight from the Old Town Square to the royal palace—there, one could no longer find the slushy mud or the rattling cobblestones.
In their place was a concrete road, smooth and seamless, as if a massive bolt of gray silk had been unrolled across the earth.
A road wide enough for two carriages to race side-by-side with ease.
The medieval disorder where people and carriages tangled together had vanished, and in its place, the majesty of a civilized path, with strictly separated lanes for vehicles and pedestrians, revealed its glory.
Public baths, public toilets, and communal laundries had been installed throughout the city, and instead of bringing out chamber pots to scatter filth onto the streets, people now used the sewage treatment plants designated for each district.
Thanks to this, the filth that used to be kicked underfoot wherever one went had disappeared. The streets, once vibrating with stench, were finally filled only with clean air and the fragrant scent of soap.
The citizens of Prague felt a sense of awe toward their King for this overwhelming change, and they called the road by this name:
‘Královská cesta’ (The King’s Road).
It had been a mere 60 days since the city’s old arteries were ripped out and that thick, gray paste was poured into wooden frames.
It was a miracle born in that short span of time.
On the day the King’s Road opened, the merchants’ reactions were nothing short of explosive.
“Your Majesty! Please sell this magical stone powder to me! I will pay double, no, triple the price!”
“Please, I beg you, let us pave the front yard of our shop with this as well! We will gladly pay any amount of ‘cleanliness tax’ you demand!”
These were the same people who had been crying and wailing when taxes were first collected.
But the moment they tasted the concrete, where carriage wheels rolled as if sliding on air, the merchants lost their minds and came running with money bags in hand.
Of course, I flatly rejected the merchants’ requests.
The production of cement was already fully allocated for the next year.
As soon as the Prague construction was finished, I had to proceed with the water and sewage works for other major cities like Kutná Hora and Plzeň. And that wasn’t even all.
I was already planning the construction of a concrete road network that would eventually connect Prague, Sternberg, and every major city in Bohemia.
The city had changed, the people’s lives had changed, and the landscape of the kingdom had changed.
But among those countless changes, there was one thing that brought me the greatest personal satisfaction.
“Hoo….”
In the Prague royal palace, in a small room secretly prepared next to my private bedchamber.
I stood up with an expression of extreme satisfaction. Then, I pulled the thin string connected to the wall.
Whoosh-!
A refreshing stream of water poured down, instantly swallowing the waste.
It was a mundane daily routine for a modern person, but to the humanity of 1421, it was a sight bordering on magic.
“Perfect.”
I smoothed my clothes and approached the washbasin.
When I twisted the brass-cast faucet, clear water gushed out. As I lathered up soap and washed my hands, the refreshing scent of lavender tickled the tip of my nose.
“This is the life of a civilized person.”
A life where one doesn’t have to expose their backside to the biting winter wind, nor endure a stench that makes one’s nose rot.
I wiped my hands with a towel and opened the bathroom door.
Just then, a familiar voice came from outside the door with perfect timing.
“Your Majesty? May I come in?”
“Come in.”
With the sound of the door opening, a maid carrying a basket in one hand slipped through the gap.
It was Sarka, my personal maid, who had been spending her busy days lately as a soap tester.
The basket she held was filled with the fresh scent of flowers.
“Your Majesty! I’ve brought the new top-quality herb soap samples that just arrived from the soap workshop.”
Sarka chattered away as she set the basket on the table with practiced hands.
“I tried them out first; the rosemary scent doesn’t lather quite as much, but the fragrance lasts for a really long time. And the chamomile scent—it makes my skin feel as smooth as silk after washing, it’s truly a marvel! It’s already causing a stir among the maids, asking when it will be released.”
“Good, you’ve worked hard. I’ll leave the real-world testing to you from now on as well.”
“Hehe, just leave it to me! My skin is so sensitive that I can tell immediately whether something is a luxury product or not after just one use.”
Sarka giggled and glanced toward the bathroom.
The sound of water draining could still be heard faintly through the pipes.
Unable to suppress her curiosity, she poked her head through the open bathroom door.
The empty ceramic toilet. The waste that had existed just moments ago had vanished without a trace, and only clean water was sloshing inside.
“Wow….”
Sarka let out an exclamation, her eyes sparkling.
“It’s truly amazing every time I see it, Your Majesty. How does it disappear so cleanly like magic without even a smell?”
“It’s not magic, but the power of civilization. Human dignity begins not with silk clothes, but with comfortable defecation.”
“What a profound saying!”
At my answer, Sarka shuddered as if deeply empathizing.
Having worked as a maid for the past ten years, she knew better than anyone the drudgery of cleaning up the waste left behind by the high-born.
“In the past, emptying the chamber pots every morning was the biggest task. Especially in winter, I had to carry the frozen pots all the way to the foot of the castle walls to dump them, and if I happened to slip on the stairs on the way… Ugh! It’s terrifying just to imagine it.”
She continued, genuinely shuddering.
“Thanks to that, you wouldn’t believe how happy the maids in the palace are these days. They say they don’t have to worry about carrying the dung-buckets as soon as they wake up, so they’re all going around shouting ‘Long live the King!’”
“Is it that much of a change?”
“‘That much’? This is innovation, innovation! Especially Božena… Ah, Božena is a maid at the laundry site, but anyway, that girl even grabbed my hands and sobbed because she didn’t have to go fetch water anymore thanks to the faucets!”
It was a testimony worthy of Sarka, a social butterfly who was close with both the housemaids and the ladies-in-waiting.
A few days ago.
While installing a bathroom in my room, I decided to overhaul the entire palace’s plumbing.
From the communal bathrooms used by the attendants to the kitchen, laundry room, and public baths. I connected water and sewage lines and faucets to every single one of them.
As the hard labor of carrying water buckets and struggling up and down the stairs disappeared, the palace’s work efficiency rose to an incomparable level.
Above all, people’s expressions brightened. The Prague palace, no longer needing to wrestle with filth, was filled with a fragrance uncharacteristic of the Middle Ages.
“These days, thanks to Your Majesty, my hands only smell like roses. It really feels like a dream.”
Sarka sniffed the back of her hand and smiled happily, then tilted her head with a thoughtful expression.
“Hmm… but Your Majesty.”
“What is it?”
Sarka asked, alternating her gaze between the bathroom drain and the city of Prague outside the window.
“Where does all the waste that goes into that hole go? Does it go into the ground and… just flow into the Vltava River?”
“Hmm.”
I rested my chin on my hand and pretended to ponder.
Sarka’s guess was half right and half wrong.
In fact, as she said, just letting it flow into the river was one method.
Currently, Prague’s population was at most around 50,000.
The Vltava River was so rich in water and fast-flowing that it was called the lifeline of Bohemia. The domestic sewage from a city of this scale was at a level that could be sufficiently handled by nature’s self-purification alone.
Rather, the real problem of medieval cities lay in the act of dumping waste on the ground itself.
Waste that seeped into the ground contaminated the soil and eventually flowed into the groundwater. People, knowing nothing, would draw that water up into wells and drink it as is.
Cholera, typhoid, dysentery.
Most of the waterborne epidemics that swept through the Middle Ages were tragedies that originated from this very act of drinking dung-water.
Therefore, simply draining waste into the river through sewage pipes would innovatively improve the city’s hygiene level. Because the well water would become clean.
However.
‘That’s what a third-rate would do.’
Dumping the city’s massive amount of waste into the river, the source of drinking water, without any treatment?
My pride wouldn’t allow it.
I am a chemist. It is my job to understand the properties of matter and control them for the benefit of all.
For me to destroy the environment for the sake of immediate convenience and feed dung-water to the people living downstream?
That would be no different from throwing my doctoral degree into the trash bin myself.
Besides, if those masses of organic matter were just dumped into the river, it would be the ultimate waste of resources.
I headed to the terrace on one side of the bedroom.
“Sarka, come here.”
“Yes, Your Majesty.”
Sarka followed behind me with quick steps.
Standing on the terrace railing, the panoramic view of the Vltava River, sparkling with sunlight, came into view at a glance.
And the new gray structures built along the riverside caught my eye.
“Do you see those square gray boxes over there by the river?”
I pointed to the terminal points of the sewage pipes. Massive concrete structures leading to the river were placed at regular intervals.
“Yes, I see them! What are those? They don’t look like watermills…”
“Those are septic tanks.”
To the eyes of ordinary people, they might look like crude warehouses, but those were the very heart of Prague’s sewage system.
I leaned against the railing and began to explain.
“The waste from the palace and the city flows through pipes and finally gathers there. And they take a very special bath there.”
“A bath?”
“Yes. Have you ever heard of lime? The white powder used when building houses.”
Sarka nodded.
“I know! It’s what you apply to walls. The stuff that gets hot when it touches water.”
“Oh.”
I didn’t expect Sarka to know this.
Janos didn’t know.
“Right. Those tanks are filled with quicklime powder. When the waste arrives there, it is immediately mixed with the lime.”
I clenched and opened my hand, mimicking the mixing motion.
“When lime meets water, it releases tremendous heat and becomes strongly alkaline. In that process, the bad germs hiding in the waste are all burned to death. This is what we call sterilization.”
“Sterilization… is it?”
Sarka tilted her head. Her eyes were full of doubt.
It was a natural reaction.
The fact that invisible microorganisms were the cause of disease was an unknown realm that humanity did not know until Louis Pasteur appeared in the 19th century.
Explaining bacteriology to a person of the 15th century was like reading scripture to a cow.
Instead of giving a complex microbiology lecture, I added an easy-to-understand analogy.
“Yes. And that’s not all. Lime has the property of making dirty debris floating in water clump together. The dust that was scattered clumps together, becoming as big as a snowball. What happens to debris that has become big and heavy?”
“Uh… does it sink to the bottom?”
“Correct.”
Flocculation and sedimentation.
It was the most basic and certain method used in the primary treatment process of modern sewage treatment plants.
Of course, it would be perfect if we could even do biological decomposition using microorganisms, but with the current technology and infrastructure, chemical treatment using quicklime was more than enough.
“That way, the debris sinks to the bottom, and only the clear water, free of germs, is released into the river. Then the river water doesn’t get dirty.”
At my explanation, Sarka’s mouth dropped open.
“My goodness… what on earth is inside Your Majesty’s head? How do you think of such things?”
“I’ll take that as a compliment. But the real part is what comes next.”
“Yes? Is there something else left?”
I grinned and pointed to the boats docked by the river. Workers were scooping something out from the septic tanks and loading it onto the boats.
“The debris that sank to the bottom. That isn’t just thrown away.”
“Ugh, what do you use that dirty dung debris for?”
Sarka frowned and mimicked holding her nose.
“‘Dirty’? To farmers, that is a treasure more precious than gold.”
“Gold?”
“Yes. The debris that has been mixed with lime and had its germs killed becomes the best fertilizer. If you scoop that out, let it age, and then sprinkle it on the fields, the wheat will grow as tall as you, Sarka.”
Sarka’s eyes grew as round as a full moon.
“Dung… becomes bread?”
“Strictly speaking, it grows wheat, but as a result, yes.”
“Woooah….”
Sarka looked back at the septic tanks by the river with an expression of disbelief.
The crude gray building, which had looked like nothing more than a dirty waste bin until a moment ago, now seemed to look like a mill grinding out bread.
Knock, knock-
Just then, a polite yet disciplined sound of knocking on the bedroom door was heard.
Sarka was startled, smoothed her clothes, and scurried back toward the door.
The speed of her transition from a curious girl back to a polite maid was astonishing.
“Come in.”
“Excuse me, my Lord.”
The door opened and Janos entered.
He gave a light bow to Sarka, who was standing to the side, and immediately got to the point.
“A messenger has arrived from the Prague Cathedral.”
“A messenger, you say?”
“Yes. It is a person sent by Priest Rokycana.”
Jan Rokycana.
At that name, I recalled the task I had secretly entrusted to him and the theologians a few months ago.
Janos spoke in a voice rarely tinged with tension.
“They say the German Bible is complete. Finally.”