Fan Wujiu rushed away.
I asked Dai Lu if she knew where Fan Wujiu was fighting. Dai Lu said that Commander Fan's Xuanjia Cavalry should be near the Sanyin Hall.
"Sanyin Hall... isn't that the rebel's territory? And the core area," I wondered, "how did she get in there?"
Don't tell me the battle situation has reversed dramatically in the past two days, and the imperial army is pushing back the rebel crystal, the underworld is too vast, and even if the rebels surrender, the progress will not be so fast.
"The Xuanjia Cavalry is a unit that is both offensive and defensive, but particularly outstanding in defense. They are the elite of the elite of the imperial court. Their purpose in charging into rebel territory is to strike at the heart of the enemy, disrupt the deployment of the outer rebels, and lure the rebels back for reinforcements—a tactic of 'encircling the point to draw out the reinforcements,' which we are all too familiar with," Dai Lu said with a smile. Every modern person is familiar with it; she must have learned it in her university courses.
"How many people, them?" I asked again.
"Not many, only three thousand. They've been deep in rebel territory for over half a month. I don't know the casualty situation—this is what I heard from my grandfather," Dai Lu pointed to the old man Dai Zi, who was next to her studying hydraulic pipes. The generational gap between them was too large, and she didn't know if he was a great-great-grandfather or something, so she simply called him grandpa.
"Then it's indeed not suitable to bring artillery," I said. "Cavalry emphasizes rapid movement. Whether artillery is pulled by horses or carried by vehicles, it cannot keep up with the speed of cavalry, unless..."
"Unless I design a self-propelled gun, haha," Dai Lu said, covering her mouth with a smile.
I waved my hand: "Don't think too much. Just create a weapon gap. If it's too obvious, people will say we're cheating."
"I know, I know. I'll disguise the Great G you gave me as a carriage later."
That's the way to do it! She learned my essence!
I didn't rush off. I took a look around and saw how Dai Lu was installing the parts into their artillery. Because she was the main designer, the dimensions were precise to the millimeter. Millimeter-level precision was enough, as it was a flexible connection, not a rigid one, allowing for some error.
Soon, the hydraulic components were installed on the first cannon. After being secured with rivets, it was pushed to the firing position. For comparison, another cannon without the hydraulic components was placed next to it.
Dai Lu was clearly doing this to show me. She first fired the old cannon. After the projectile was shot, due to the strong recoil, the cannon slid backward more than three meters. Bing Bing, who didn't quite understand weapon construction, asked in a low voice, "Why don't you use stones to block the cannon's wheels? Like putting bricks under a car's wheels to prevent slipping?"
"The recoil of the cannon is far greater than its potential energy. If you block the wheels with stones, the recoil will be directed vertically, and the cannon will jump up. Think about it, if a row of concentrated cannons fires simultaneously, and the cannons jump around, what happens when they collide with each other? What happens if they hit the shell crates behind them?" I explained.
"Oh," Bing Bing nodded, "so that's how it is. Then what's the use of this little thing?"
"You'll see," I said with a smile.
Because the cannon had retreated more than three meters, it was about to hit the shell emplacement behind it. Moreover, more importantly, the muzzle direction had significantly deviated laterally. With a retreat of over three meters, the two wheels could not travel in a perfectly straight line. Even a deviation of one or two degrees would cause a large difference in the target direction, tens or even hundreds of meters, meaning it wouldn't hit the enemy.
The bare-chested, robust yin soldiers had to push it back to its original position, re-aim, and by the time the next shot was fired, two minutes had passed.
Bing Bing was so bored that she yawned, "So slow! With this much time, the enemy cavalry would have charged over."
"Cannons without a recoil brake, this is already considered fast," I said.
Next, the same artillery crew came to the new cannon and operated it according to Dai Lu's instructions. Dai Lu asked two soldiers to hold the cannon wheels with their hands. The two soldiers were very confused. Under normal circumstances, if they tried to stop the recoil of the cannon with their bare hands, their arms would be torn off!
"How about I do it?" Dai Lu said with a smile.
The yin soldiers naturally dared not let her personally hold it and could only trust the results of Madam Dai's scientific research, assuming it wouldn't hurt them.