While the Korean army was reporting their victory near the Yalu River, Hyang was still moving busily.
"Is the river connection mostly finished now?"
"Yes, Your Highness."
Hyang and the officials were discussing while looking at the large map spread out on the table.
'The goal is to connect all the rivers in Hanyang, centered around the Cheonggyecheon and major rivers, to solve the sewage problem.'
If this was the ultimate goal of Hyang's plan, the work done so far was the first phase, which involved primarily repairing small rivers in areas where houses had been completely destroyed by fire.
According to Hyang's plan, the exposed rivers were connected using sewers.
Most of the sewers were open channels on the ground, but those crossing major roads were buried underground by digging trenches.
Of course, for this work, a large number of sewers made using quicklime and rebar from District 51 were supplied.
* * *
"Making sewers with quicklime and rebar? That's amazing."
"It's called reinforced concrete."
"Reinforced concrete? I've never heard of it."
Not only Sejong, who was receiving the report, but also the ministers were puzzled by the unfamiliar term.
"It's a combination of Chinese characters and Western words. The Westerners call the mixture of quicklime, sand, and gravel 'concrete.' I couldn't think of a suitable name, so I used it as is. I'm sorry, Your Majesty, for my lack of skill."
"No, the Crown Prince has many tasks to do, and time is limited. It's an inevitable situation that everyone understands. We'll think about how to change that unfamiliar name later. What do you think, ministers?"
In response to Sejong's question, the ministers all bowed and answered in unison.
"It's a proper decision!"
However, there were people who were in an uproar over Sejong's decision.
They were the scribes writing the official records and the clerks of the Office of the Royal Secretariat who were taking shorthand.
'How are we supposed to write "concrete"!'
The scribes and clerks were momentarily in a state of panic and froze.
"By the way, what is the utility of combining rebar and concrete?"
As Sejong asked about the utility, the scribes and clerks regained their composure and started writing furiously with their gold pens.
The problematic word 'concrete' was left blank using parentheses, which were becoming more widely used in documents centered around the Jiphyeonjeon and research institutes.
Hyang explained the utility in response to Sejong's question.
"Yes, mixing quicklime, sand, and gravel is like artificially making stone. This stone is strong against compressive forces but weak against tensile forces."
"Is that so?"
Sejong's question was immediately answered by the Minister of Personnel.
"That's correct. That's why in quarries, they use the method of inserting wedges into cracks and pulling them out with ropes to extract stones."
"I see, so what?"
"Iron, on the other hand, is strong against tensile forces but weak against compressive forces. By combining these two, we can complement each other's weaknesses and enhance their strengths."
"Hmm~."
"Wow! Such a method..."
Hyang's explanation elicited exclamations of admiration from various parts of the hall.
"Wow~, this is truly a symbol of harmony using the mutual generation and overcoming of the Five Elements! What a brilliant method!"
Sejong, as well as the ministers, were genuinely impressed.
* * *
"Good to hear. You must be busy with disaster recovery, so you may go."
"Your grace is boundless."
Hyang, who had finished the report that started with sewers and ended with reinforced concrete, bowed to Sejong.
As Hyang left, Sejong looked at the ministers.
"Let's take a short break."
"Your grace is boundless!"
As soon as Sejong declared a recess, the scribes and clerks rushed out of their seats.
"Hmm?"
Sejong, puzzled by the behavior of the scribes and clerks, quietly followed them.
"Your Highness! Your Highness!"
Hyang, who had stopped to discuss the construction status with those waiting outside the hall, stopped when he heard someone calling him.
"What is it?"
"Ah, ah, ah. Your Highness... that... that..."
"Take a deep breath and speak."
"I'm sorry, Your Highness."
"And you should exercise more. It's not that far from the hall to here... tsk!"
While the scribes were catching their breath, their faces red from Hyang's reprimand, Hyang continued discussing with the officials.
"Actually... how should we write the word 'concrete'?"
Without turning around, Hyang extended his hand.
"Paper, ink, and brush."
"Here it is, Your Highness."
As the scribe hurriedly handed over the writing board and gold pen, Hyang absentmindedly started writing.
"Conc... Ah!"
"Your Highness!"
Suddenly, Hyang let out a scream, causing everyone around him to panic.
"It's nothing, it's nothing."
Waving his hand to calm the people, Hyang dipped the gold pen in ink and heavily smeared the written characters. After thoroughly erasing the characters, he wrote new ones.
'Concrete'
"Write it like this in Western script. If you can't think of a suitable ideogram, just use these characters."
"Yes, Your Highness. I'm sorry."
"Then, I'm busy, so..."
After confirming that the characters were properly erased, Hyang slowly walked away.
'Phew! That was close!'
While maintaining a calm expression, Hyang was trying to calm his wildly beating heart. He crossed the threshold of Gwanghwamun.
'Pull yourself together! Hyang! You almost caused a major accident, a meteor-level accident!'
Distracted by discussing the construction site, he had almost unconsciously written 'concrete' in Hangul.
Fortunately, he noticed and erased it halfway through, but his back was still drenched in cold sweat.
'If anything goes wrong, I'm finished! Voluntary hobbies are welcome, but forced hobbies are a no-go!'
"How do we translate this...?"
The scribe, who had learned the word from Hyang, pondered as he returned to the hall.
The other scribes and clerks walking alongside him were also struggling to find a suitable word.
"Should we use fanqie (εε)?"
"That seems best... The problem is 'ν¬' and 'νΈ'. 'μ½' can be 'μΎ' and 'μ¨' combined..."
While they were discussing how to write 'concrete' in a suitable way, Sejong called them.
"Hey, scribes and clerks. Come here."
"Yes, Your Majesty!"
"Okay. What did you ask the Crown Prince?"
"Ah... how to write 'concrete'."
"Can I see it?"
After a brief discussion, the scribes respectfully handed the writing board to Sejong.
"It's not an official record... it's possible."
Sejong took the writing board and read the word written on it.
"Con... crete..."
As Sejong read the word, the scribes and clerks' eyes widened.
"Can Your Majesty read it?"
"While reading the Western books the Crown Prince brought, I learned it. But... what is this ink smear?"
"He suddenly smeared it."
"Suddenly? What kind of character was it?"
One of the scribes, who had a keen eye, answered Sejong's question.
"A character I had never seen before."
"Never seen before? Not the Western character written here?"
"Completely different."
"Is that so?"
After a short response, Sejong thought for a moment and returned the writing board to the scribe.
"You saw it well."
"I'm sorry."
"By the way, if you remember what it looked like, write it down."
"From a quick glance... Ah!"
The scribe, who let out an exclamation, wrote a character on the writing board.
"He wrote two characters, both starting with the same shape."
Sejong took the writing board and looked at what the scribe had written.
'kk'
"..."
Sejong frowned and tilted his head, then returned the writing board to the scribe.
The scribe, who received the writing board, bowed respectfully and returned to the hall.
After sending the scribes and clerks away, Sejong stood like a scarecrow, lost in thought.
'The character, or rather the symbol, written by the scribe is indeed a character I've never seen before. Is it from India or the Muslim world? No, I don't know any similar characters. And, with Western words and characters available, there's no need to use characters from India or the Muslim world. The same goes for the characters of the Jurchens or Mongols... So, did he simplify Chinese characters himself? It's not impossible, but there was no need to smear it so thoroughly...'
What started as mere curiosity was growing in Sejong's mind.
Sejong remembered a meeting at Jeongcho's house not long ago.
'The Crown Prince's excellence is known to all, but few know how excellent he is. Why? Because he tries not to reveal himself too much. Why is that?'
As Sejong pondered, he muttered to himself.
"He used tricks to do what he wanted. What a sly guy."
"Your Majesty?"
"It's just a mutter."
In response to Sangsun's question, Sejong briefly answered and continued to organize his thoughts.
'The guy subtly mentioned our own script not long after being designated as the Crown Prince. And the most important thing is the phonetics books... he had already read them all when