The setting was the Celuroa Kingdom.
The time was June 21, 3457, roughly six months earlier.
It was the day Jin unveiled his airship at the Technology Expo in the Shouro Empire.
“Hmm, an ‘airship,’ you say?”
“Yes. Rather than a sphere, it is elongated—shaped like an egg, so to speak. It appears to float by filling a bag with some kind of lightweight air.”
In addition to official participants like Stearena Gamma, the Celuroa Kingdom had several spies embedded at the Expo to gather information. They had been relaying data about Jin’s airship back to their homeland.
“Hmph... To think those upstarts would develop a technology our kingdom lacks.”
Richard Valois de Celuroa, the King of Celuroa, was in a foul mood.
“...Rambeau! Develop the same thing for our kingdom... no, develop something even better!”
“As you command, Your Majesty.”
Rambeau, the Chief of the First Ministry of Internal Affairs, received the order and immediately set things in motion. Latant, the Chief of the First Ministry of Technology, was given the directive, and the Ministry of Technology devoted its full resources to the project.
“Hmm, what exactly is this ‘lightweight air’?”
As a nation that already possessed hot air balloons, they understood the concept of gathering light air to achieve buoyancy. However, a gas capable of such lift was currently unknown to them. The Ministry of Technology had to begin their project by searching for this mysterious gas.
Then, one day...
“Chief, this man has something to report.”
A young alchemist, who had joined the Ministry of Technology only the previous year, stepped forward.
“Sir, if you immerse iron in the liquid that pools in the depths of the Nubari Mine, it releases a lightweight gas.”
“What? Is that true?”
“Yes. I have tested it several times. However...”
“However, what?”
“The gas... it is flammable.”
“Hmm. We simply need to ensure no fire comes near it. Let us begin experiments at once.”
Over the next few days, they procured samples of the liquid from the deepest tunnels of the Nubari Mine. The reports that the liquid dissolved iron were accurate; to transport it, they required containers made of gold or silver.
“I see. It certainly dissolves the iron.”
When scrap iron was immersed in the liquid stored within a silver container, it produced fine bubbles as the metal dissolved.
“And these bubbles are the lightweight air?”
They constructed a hemisphere roughly fifty centimeters in diameter using the same material as their hot air balloons—linen fabric impregnated with soft magi-resin—and collected the gas inside.
“Oh! It actually floats!”
When released, the hemisphere drifted slowly toward the ceiling.
“Excellent. This settles the matter of the gas.”
In all likelihood, this liquid was concentrated sulfuric acid or an acidic solution containing it. While dilute sulfuric acid does not dissolve gold, silver, or—under certain conditions—copper, it reacts with iron and zinc to generate hydrogen.
Since zinc was less abundant than iron, they chose to generate their hydrogen using scrap iron. The gas bags were made from the same magi-resin-soaked linen used in their hot air balloons.
The first prototype, a fifteen-meter-long vessel capable of carrying two people, was completed on September 29.
“Ho, this is quite interesting.”
King Richard was in high spirits when he inspected the prototype.
“How does it achieve propulsion?”
“Sir. It moves forward by applying wind magic to itself.”
“Hmph, a clever approach.”
Coincidentally, they had arrived at the same propulsion method that Eckart Techles had used for his large ship.
“With this, we can achieve double the speed of a hot air balloon.”
“I assume that also depends on the aerodynamics of the gas bag?”
“Precisely, Your Majesty.”
“Very well. I recognize this prototype as a success. Construct a larger version next, then move to mass production.”
“Understood!”
With King Richard’s approval, the Ministry of Technology set out to build a sixty-meter-long airship. Generally, the lift efficiency of an airship improves with size; while buoyancy increases proportionally to the cube of its dimensions, the weight of the structure increases at a much slower rate.
Drawing on the full might of the Ministry of Technology, the airship was completed on November 2.
“Magnificent. This is truly impressive.”
King Richard offered rare praise upon seeing the finished vessel. The sixty-meter airship was indeed a sight to behold.
“This shall be our kingdom’s secret weapon.”
The King immediately ordered the mass production of the same model.
＊ ＊ ＊
January 7, 3458.
“N-No! Do you have any idea how much I sacrificed to build this ship?!”
“Silence! This is by order of His Majesty the King!”
Soldiers stormed the estate of Eckart Techles, a wealthy merchant in the southern town of Koup. They seized all his household property and the large ship Bridget—a vessel he had poured his very life’s blood into building.
“Ho, so this is the ship.”
The Bridget was brought up the Naudaria River to a site near the capital, Esaia. King Richard remained in a pleasant mood for the rest of the day after inspecting it.
“Our kingdom’s technological prowess is truly second to none.”
“Indeed, Your Majesty. We already have two more ships of the same design under construction.”
“Excellent. I look forward to their completion.”
＊ ＊ ＊
Then came the fateful day of January 10.
“What? You say magi-crystals and five hundred golems were discovered within the Leonard Kingdom’s borders yesterday?”
“Yes. This is a report from our spies embedded in the Kingdom of Egerea.”
“Hmm... It would be a waste to let them fall into their hands. Who is nearest the border? Order the 2nd Frontier Corps to secure those magi-crystals and golems immediately.”
“As you command.”
As the aide turned to relay the order, King Richard called him back.
“Wait. That is not enough. Dispatch an investigation team from our own borders as well.”
“Yes, Sire!”
This time, the aide hurried off. The 2nd Frontier Corps was dispatched to the Soldrake Ruins where the five hundred golems were reportedly found, while the 1st Frontier Corps was sent to investigate the Former Leonard Kingdom.
＊ ＊ ＊
“What?!”
On January 26, news reached King Richard that sent him into a rage.
“The 2nd Frontier Corps was wiped out? Because of magical beasts surging from underground? Don’t be absurd!”
“I am afraid so, Your Majesty. This is an official notification from the Kingdom of Egerea.”
The Chief of the First Ministry of Internal Affairs broke into a cold sweat as he watched the King’s temper flare.
“They stated they would eventually return the soldiers’ personal effects.”
“Grrr... Magical beasts, my foot! It must have been an ambush by those Egerean dogs!”
“Even if that were the case, we have no evidence, Sire,” the pale minister argued, though his words did little to soothe Richard’s fury.
“Those Egerean fools, they dare mock me...”
Just then, a messenger burst into the room.
“Your Majesty! A pigeon report from the 1st Frontier Corps! They have discovered vast quantities of Elradrite and ancient artifacts at the Elrad Ruins!”
“Oh! Is that so?!”
This report finally lightened Richard’s mood. He reached a decision then and there.
“Very well. We shall invite the heads of state from every nation to our Founding Anniversary Ceremony on February 22. There, we shall show the world our kingdom’s true might!”
However, no one yet realized that this moment would mark the beginning of a massive turning point for the Celuroa Kingdom.