The Ausser Army's sabotage operation against the dwarf tunnels was a far greater success than expected. The powerful explosives made from picric acid demonstrated in actual combat completely overturned the traditional understanding of demolition warfare.
Unlike black powder, TNT is a true high-energy explosive. Its explosion mechanism is not combustion, but detonation—a chain reaction of chemical reactions that propagates at supersonic speeds. Its shock wave travels at speeds exceeding 7,000 meters per second, far exceeding the speed of sound, and can tear and pulverize rock from the inside in an instant.
Black powder, though now commonly referred to as "explosive" in Northwest Bay, is actually a low-velocity explosive. Its essence is to generate thrust through rapid combustion, or deflagration, and then rely on the expansion of gas in a confined space. If black powder is ignited in the open, it will only produce a ball of fire and thick smoke, and cannot create a destructive impact. Only by sealing it in the barrel of a cannon, in a rock hole, or in an iron pipe can it "explode" the target.
This is why, in the past, when using black powder blasting, the sappers of the Northwest Legion had to drill holes, fill them with explosives, compact them, and seal them with mud. The slightest oversight would result in nothing more than a firework. Even if successful, it often only cracked the rock mass, making it difficult to completely destroy it.
However, picric acid is different. Even when ignited in an open environment, it will cause a violent explosion, known as detonation, which will produce a powerful shock wave and destructive force. This is fundamentally different from gunpowder.
During this operation, the yellow explosives were able to trigger a violent explosion inside the not-completely-sealed tunnel. The three charge points detonated in succession, directly collapsing the main passage and ultimately completely sealing off the entire tunnel.
Over the past six months, the Department of Chemistry at Weiss Academy has made numerous key improvements to transform picric acid from a laboratory finding into a combat-ready military explosive.
Initially, crude picric acid was extremely unstable; friction, impact, or even temperature changes could trigger an accidental explosion, which once seriously injured a researcher. To address this, Hoffman led a purity control study, removing impurities through multiple recrystallization processes, which significantly improved its stability.
Subsequently, Wells discovered that pure picric acid was still sensitive to impact. Referring to the "desensitization" idea provided by the lord, he tried to mix it with inert substances. After dozens of experiments, he finally determined that picric acid crystals should be melted together with 10% beeswax and then cooled and shaped. The beeswax would then coat the crystals to form a buffer layer, which greatly reduced mechanical sensitivity without affecting the explosive power.
In addition, to prevent the explosives from failing in the damp tunnel, the Department of Chemistry developed a double-layer encapsulation process: the inner layer is a paraffin coating, and the outer layer is sealed with tin foil, then placed in a wooden tray and a metal box. The fuse system was also improved from the traditional match cord to a mercury fulminate primer + detonating cord, ensuring reliable detonation even in high humidity and oxygen-free environments.
After three months of testing and optimization, Weiss Academy finalized the design of "Type 01 Insensitive Bitter Acid Explosive": a yellow wax-sealed block, each weighing one pound, drop-resistant, moisture-resistant, and capable of long-term storage.
It was this standard explosive that demonstrated its revolutionary power in demolition demonstrations and tunnel blockade operations outside the Mountain Throat Fortress. From unstable crystals to military standard products, the past six months of research and development has not only been a technological breakthrough, but also signifies that Alda's military research and development is moving from experience-based exploration to systems engineering.
Derrick sat in the Mountain Throat Fortress's office, his fingers trembling slightly as he held a quill pen. On the map spread out on the table, the entrances to several dwarven tunnels were marked with red circles, like a hunting net waiting to be harvested.
He took a deep breath and began writing rapidly on the paper.
To Lakeheart Town Staff Department: The new explosives have been successfully used in combat, with results far exceeding expectations. All three main tunnels in the Eastern Rocky Mountains have been completely sealed off, trapping the dwarven forces used to ambush us. They cannot be reopened in the short term. This explosive is undoubtedly key to our swift victory over the dwarves. We urgently request at least 100 pounds more to clear the remaining known tunnels. Our current stockpile is only two boxes, which is insufficient. We hope to receive reinforcements quickly.
After writing the letter, he personally sealed it with wax and sent it to Winds Breath Keep's Telegraph site as quickly as possible.
The Lakeheart Town Telegraph system has been extended to Winds Breath Keep in Yellow Earth Plain, relaying messages from station to station using semaphore codes. By that evening, the contents of this urgent message had already appeared in Lakeheart Town. At the Staff Department meeting.
The following morning, a reply was sent back to Winds Breath Keep in the same manner, and then delivered by fast horse to Mountain Throat Fortress.
When Derrick opened it, he saw not only approval, but also a series of stern warnings:
"The second batch of yellow explosives, totaling 120 pounds, is being transported by wartime railway from the Eastern Front Arsenal to Yellow Earth Plain. It is expected to arrive within seven days. Your unit needs to send a special team to the final destination to receive it."
"To reiterate: This substance is extremely unstable. Friction, impact, and high temperature can all trigger an explosion. All personnel handling this substance must undergo rigorous training. During transportation, it must not be jostled. It must be stored in different locations in a cool, dry place, and smoking is strictly prohibited."
"Life is paramount, and we must not let down Marquis and the scholars of the Chemistry Department. If anything goes wrong, it will not only result in casualties, but also destroy our weapon of victory against the dwarves."
After reading it, Derrick, who was somewhat smug from his victory, became cautious again.
He summoned his adjutant and ordered a group of steady veterans to come to Deson for training in handling explosives. They were also tasked with clearing out separate storage areas in different locations within the fortress and setting up sandboxes and isolation zones as requested in the letter.
After more explosives arrived at Mountain Throat Fortress, Derrick ordered a full-scale clearing operation.
"Find the tunnel, blow it up," he said at the war council. "Don't they like to go underground? Let's keep them from coming out."
Guided by scouts, the Ausser Army began to penetrate deep into the ridges of the Eastern Rocky Mountains. Wherever they discovered the entrances and exits of the dwarf tunnels, regardless of size or whether there was enemy activity, they planted explosives and detonated them on the key support sections.
Often, a single blast can cause the entire tunnel to collapse, the rock strata to fracture, and rubble to block the tunnel for tens of meters, making it impossible to clear in a short period of time.
The dwarves' prized tunnel network began to crumble, with tunnels originally used for ambushes, relocations, and raids being destroyed one after another, and several outposts losing contact.
They attempted to organize a counterattack, but in the Ausser Army Under the precise volleys of the firearms, once exposed on the ground, they became sitting ducks. The range and rate of fire of the flintlock muskets far exceeded that of the dwarves' shortbows and slings; after three volleys, the charging dwarf formation had already fallen by more than half.
Stonemason Clan was forced to abandon many strategic locations, and its remnants retreated deeper into the mountains. Ausser Army, on the other hand, advanced steadily, sealing off all tunnels along the way with each step forward, leaving no way out and no hidden dangers.
And so, they gradually approached the core area of the Stonemason Clan territory.