Hyang’s concerns deepened as he weighed his personal desires against the Empire’s current technological level and finances.
“What I want to make first is a tank, but without internal combustion engines, I can’t escape from this infinite hell…”
***
When Hyang used steam engines to create tractors—modified towing vehicles—Sejong had suggested mounting artillery on top of them.
However, this couldn’t be realized due to safety concerns.
The characteristics of steam engines as external combustion engines were the problem.
Placing gunpowder and shells near a firebox with constantly flickering flames was extremely dangerous.
An alternative of building bulkheads between the powder magazine and engine compartment was proposed, but this would make the vehicle too large.
No, steam engines themselves were unsuitable for tanks.
A steam engine powerful enough to be effective would be considerably large and heavy.
Since Ming, the primary enemy during initial planning, also had artillery, considerable armor thickness was needed to withstand Ming’s artillery attacks.
This began a vicious cycle.
“The tank must be large to protect the steam engine’s bulk and artillery.”
“Armor plating is needed to break through enemy lines while withstanding Ming’s bombardment. And it must be large and thick enough to cover that huge bulk.”
“Thick armor increases weight, so the steam engine’s output must increase.”
“When the steam engine’s output increases, it becomes larger and heavier.”
“And so on, infinitely.”
In this impossible situation, the only solutions that emerged were armored self-propelled cranes for combat engineers and armored towing vehicles.
The self-propelled crane armored to protect engineers in combat literally boasted a bulk “like a dozens-of-rooms-wide tile house moving on its own.” And this was despite only mounting Model Eul gun carts for self-defense instead of artillery.
The armored towing vehicle involved a tractor wrapped in appropriately thick iron plates pulling similarly armored carts mounted with artillery.
Since its mission was to bombard enemies from positions slightly removed from the frontline battlefield, it adopted thin armor, making it barely developable as a weapon.
“Really now… I should call this self-propelled artillery, not a tank.”
As Hyang muttered to himself, it was closer to self-propelled artillery than a tank.
In a way, these were nearly failed weapons. However, thanks to their somewhat impressive performance in the Battle of Liaodong Fortress, the Imperial Army continued using them.
***
“Damn… To make internal combustion engines, Texas is still far away… And near the mainland, the only places with crude oil are in Ming’s core regions, so we can’t touch them…”
The famous Texas oil fields were still pie in the sky.
The Empire was diligently expanding its territories in the New World. However, they couldn’t focus full effort eastward due to concerns about the Atlantic, and the south had not only just begun but was blocked by jungles.
The west?
They hadn’t even properly started westward, and damned deserts stood in the way.
That’s why Hyang mentioned Ming.
Ming, the Empire, and Japan all knew about crude oil.
It was already mentioned in the Book of Han as “oil water,” and Song dynasty’s Shen Kuo wrote about petroleum in his book ‘Dream Pool Essays.’
Chinese historical records even documented using this crude oil for fire attacks. Not only that, but pitch for coating ships and Ming’s famous ink also used crude oil as the main ingredient.
Therefore, Ming already had several places where crude oil seeped out from long ago.
The problem was these regions were in traditional central Chinese territories.
Even the Empire could seize these regions but couldn’t rule them.
The Manchurian region secured through the Liaodong battles had the famous Daqing oil field, but there were problems here too.
Hyang didn’t know the exact locations of these oil fields, drilling technology was lacking, and the biggest problem was that Hyang didn’t know how to refine crude oil.
“I know distillation is the basis, but…”
As Hyang said, crude oil refinement was based on distillation. However, properly refining crude oil required chemical knowledge and technology to support it.
And the Empire still had a long way to go in this area.
***
“The conclusion is that crude oil, internal combustion engines, and electricity are all going into the miscellaneous records…”
Hyang concluded with an expression full of regret.
Already entering old age, Hyang was making his own preparations.
He was listing the hobbies he would pursue after handing over to Wan and returning to the mainland, and creating his own ‘miscellaneous records.’
“Originally, I was going to do only the hobbies possible now and bury everything else…”
Hyang had intended to bury all future knowledge and technology he knew except for what was possible as hobbies and what was possible at the current level of the Empire’s scholars.
However, influenced by the miscellaneous records Sejong had passed on just before his death, Hyang changed his mind.
“If the level of the miscellaneous records left by His Majesty the Venerable Emperor is this high, it should be fine to leave some.”
Having decided this, Hyang began writing his own miscellaneous records.
And this had its own practical considerations.
“Honestly, I know things but at the current level, we can’t even grasp the concepts properly, so it seemed a waste to bury them. But there were limits to me doing everything myself.”
Whether electricity or internal combustion engines, if he ground up scholars and craftsmen based on the concepts and knowledge Hyang knew, they could achieve some results. However, persuading the scholars and craftsmen was the problem.
“If they ask how I knew, it’s hard to explain. ‘I just thought of it’ has reached its limits now… Especially that damned ‘oxygen’ and ‘combustion’… Phew~. If I go a little further, the ‘Hyang is an alien’ theory will become established fact.”
Knowing these limitations, he decided to leave the knowledge he was going to bury as miscellaneous records.
“It’s only possible because of the Venerable Emperor’s miscellaneous records. This way, I’ll just remain as ‘a person with unique perspectives and thoughts.'”
With these calculations, Hyang began creating his miscellaneous records.
As an aside, Sejong’s and Hyang’s miscellaneous records were treated as top secret among top secrets along with the Challenge Records. And when they were finally made public after much more time had passed, they became the center of historical controversies and all sorts of conspiracy theories.
***
While Hyang was struggling between his personal desires and practical limitations, an official request arrived from the mainland.
Receiving the official request submitted by the Imperial Army’s Ministry of Defense and approved by Wan, Hyang’s eyes lit up.
“This I expected… Hm? What’s this? I didn’t expect this?”
What Hyang expected was mass production of the ‘Model Gap Light Combat Vehicle.’
Imperial Army commanders who participated in the Mexica conquest submitted reports highly praising the combat vehicle’s effectiveness.
After reviewing combat reports written during the conquest and post-war analysis reports, the Imperial Army high command and Ministry of Defense brought in combat vehicles from the New Territories for field testing in the northern territories.
When evaluations from the northern territories also came out very positive, the Ministry of Defense decided to officially adopt the Model Gap combat vehicle.
With this decision, the Model Gap combat vehicle transformed from a regionally specialized weapon used only in the New Territories to a weapon used throughout all the Empire’s territories.
On the other hand, from the perspective of nations hostile to or wary of the Empire, another “damned troublesome Imperial weapon” had been added.
The official adoption of combat vehicles had significant impact on the New Territories.
Following Wan’s orders, Model Gap combat vehicles would be produced in the New Territories and supplied to the Imperial Army.
Until then, all funds for developing the New Territories had been supported from the mainland.
In this situation, production payments for Model Gap combat vehicles going to the New Territories meant the New Territories were finally beginning to develop self-sufficiency.
In a way, it was similar to “playing with numbers,” but it was a very symbolic event.
***
If the “official adoption of Model Gap combat vehicles” was within Hyang’s expectations, there was something he hadn’t anticipated.
“They want me to make a ‘grenade launcher’?”
Receiving another request from the Imperial Army, Hyang wore an expression of surprise.
The performance requirements for the weapon requested by the Imperial Army could be summarized as follows:
“A firearm capable of launching shells with power similar to grenades farther than thrown grenades.”
“Operable by one or two soldiers.”
“Requiring minimal time for education and training.”
Checking the “required performance” set by the Imperial Army, Hyang tilted his head slightly.
“What should I call this? Rifle grenade? Grenade?”
Behind the Imperial Army’s request for such a weapon was the ‘Mexica Battle.’
In jungle combat in the Mexica region as well as urban warfare in Tenochtitlan, the Imperial Army had made excellent use of grenades.
While their power was much weaker than thunder-crash bombs, grenades were far superior in portability.
All Imperial Army commanders who participated in the battles at that time focused on this portability.
However, there were regrettable points.
Since they were thrown by people, they couldn’t fly far.
The Imperial Army high command, after reviewing reports from participating commanders, all nodded.
“Grenades are certainly convenient to carry around and use.”
“I agree. Thunder-crash bombs are certainly effective, but they absolutely require mortars…”
“And there’s a limit to constantly dragging those mortars around…”
“The problem is grenades don’t fly as far as thunder-crash bombs compared to mortars. No matter how good soldiers are at throwing, they can’t compare to mortars.”
“I agree.”
Thus, the Imperial Army decided to develop a grenade launcher.
Following the Imperial Army’s decision, Area 51 craftsmen began developing grenade launchers.
However, seeing the grenade launchers made by the craftsmen, the Imperial Army leadership all wore peculiar expressions.
“The performance seems fine, but something seems lacking…”
“I agree. Something seems a bit lacking, but what…”
When similar results came from subsequent field evaluations, Wan immediately requested development from Hyang.
***
Learning the circumstances through records sent by the Imperial Army, Hyang nodded.
“Indeed… There are problems.”
“Power similar to grenades”
“Fly farther than thrown grenades.”
“Operable by 1 or 2 soldiers.”
In Hyang’s memory too, there were several weapons satisfying these requirements.
“There are rifle grenades, grenade launchers, 60mm mortars, and the famous Japanese knee mortar…”
All satisfied the Imperial Army’s requirements but had different advantages and disadvantages. That’s why, except for the knee mortar, these other weapons continued to be used even into the 21st century.
“Hmm… Then my choice is… Considering the Empire’s current technological level…”
Among the various candidates that came to mind, Hyang chose the M79 grenade launcher.
“Of course, I can’t make the grenade’s detonation and safety mechanisms exactly the same… But it should still earn its keep.”