Scouts of the Great Qian quickly discovered the cavalry of the Gui Shuang Dynasty, accompanied by ten thousand elites. They immediately returned to report.
"The enemy has dispatched cavalry to harass and probe the border, intending to provoke conflict," Lü Yi stated with a grave expression.
The generals eagerly requested to be dispatched.
Only Heraclius hesitated, wanting to speak but holding back.
Lü Yi inquired curiously, "Do you wish to avenge past grievances?"
Heraclius shook his head. "Marshal, this could very well be a stratagem to lure our forces. If we win, it won't force the enemy to retreat. If we lose, Yumenguan might fall. I still suggest we temporarily hold the enemy at bay until Yumenguan is sufficiently reinforced. Their long supply lines mean greater consumption."
Lü Yi chuckled. "Your opinion aligns perfectly with Liang Xiao's. Back when Liang Xiao served as Deputy Grand Marshal of the Northern Frontier, he proposed reinforcing Yumenguan. Over the past few years, Yumenguan has been expanded. The western wall is now up to eight zhang thick at its thickest point and at least six zhang at its weakest. The other walls are at least four zhang thick. This is to eliminate any risk of the city being breached. Now, this pass is as formidable as the treacherous Jiange."
Heraclius exclaimed in surprise, "Could Marquis Anguo have known about the enemy's trebuchets? No, trebuchets would have no chance of breaching Yumenguan's walls, not even getting close..."
Lü Yi smiled. "Liang Xiao said that trebuchets are ancient relics and will eventually be phased out by the times. This may sting the Romans a bit, but it's true. Our army's new type of catapult is called the 'Huihui Cannon,' and you've witnessed its power..."
In truth, he didn't know why Liang Xiao placed such extreme importance on Yumenguan's walls, even before a major victory against the barbarians. He had instructed him to notify the western border commanders to reinforce it beforehand, emphasizing "at any cost."
Logically, walls three to four zhang thick were already sufficient.
The Great Qian nation had spent considerable wealth and manpower to reinforce Yumenguan.
However, out of trust in Liang Xiao, Lü Yi continued the reinforcement.
Liang Xiao's original request was for the western wall to be seven zhang thick at its highest and at least five zhang at its lowest. Lü Yi pondered, since they were building anyway, why not build more? He added another zhang of reinforcement on top of Liang Xiao's specifications...
This was because Lü Yi suddenly remembered Liang Xiao's "powder kegs."
What if the enemy had them too?
To prevent Yumenguan from falling, Liang Xiao dispatched a large number of triple-bow ballistae, Divine Arm Crossbows, improved catapults, and powder kegs to the western frontier, forbidding any enemy advance.
South of Yumenguan, Achilles, who was leading the cavalry to harass the area, wore an extremely grim expression.
From the temporary earthen mound he stood on, his exceptional eyesight could see clearly.
Yumenguan was more than twice as thick as they had imagined!
"These damned wretches! The Gui Shuang Dynasty had never seriously threatened the Great Qian before, so why did they build Yumenguan into such a formidable pass!!"
Facing such a mighty pass, Achilles realized that with only a force of a hundred thousand men, it would be impossible to conquer it.
Circumventing it was fraught with peril.
Helpless, Achilles could only return to inform his brother, Mars.
Mars's brow furrowed. "According to the Great Qian's current measurement system, the city walls are at least six zhang thick? With their bizarre siege weapons, I fear even a whole squadron of our trebuchets couldn't breach them! I've heard that the Great Qian prohibits unauthorized personnel from approaching any large machinery, making it impossible for spies to gather accurate intelligence. That's the real trouble."
"Didn't you say Western light crossbows are inferior to Eastern ones, but heavy trebuchets completely outperform Eastern ones? What kind of rubbish did you replicate? The Great Qian's catapults are clearly more powerful than our trebuchets, and they are vastly different from the catapults of the Great Zhou described in our historical records!" Achilles roared.
Mars's face immediately darkened. "I suspect the Great Qian has improved their catapults. Their principles are likely close to the trebuchets we replicated, possibly even more advanced... It seems we cannot solely rely on trebuchets. Fortunately, the rear is still preparing siege equipment for scaling walls. Regardless, we must tie down a main force of the Great Qian at Yumenguan. The Tian Ri tribe's focus should now shift to a joint attack on Jiangnan and containing the desert!"
Achilles fumed, "If I have to detour to the Peacock Dynasty, or even Jiaozhou, it will take at least half a year!"
Just then, an urgent report arrived from afar: "Marshal! The twenty thousand Xianbei cavalry from the desert have been repelled by Marquis Anguo Liang Xiao of the Great Qian, with over nineteen thousand beheaded! This news has spread throughout the Great Qian!"
"How is that possible?" The two brothers cried out in unison.
Calculating the time, it had only been half a year since they received news from Valentin!
"We must spare no expense and increase the troop and logistical mobilization of the Gui Shuang Dynasty. We absolutely cannot allow the Great Qian to redeploy too many forces to reinforce Jiangnan!!" Mars, with an uncharacteristically ashen face, furiously ordered.
In the capital, Liang Xiao was accompanying his wife and children at the West Palace Villa.
Yue Lian not only cooked for the children herself but also taught them literacy. Jian Qin taught them music, Ke Li Si taught them reading, and Zhuo Xun was in charge of chess and painting. The children studied according to their own interests.
As for martial arts training, it would have to wait another year or two. There was Jian Nanfeng's swordsmanship, Zuo Wuji's spearmanship, Zuo Wushang's combat skills, Zuo Jing's grappling techniques, and if necessary, their father would personally instruct them...
"Marquis, Assistant Minister Zhang requests an urgent visit."
After Ning Xuejun announced this, Liang Xiao immediately left the West Palace Villa and went to the Ministry of Works with Zhang Yang.
Zhang Yang produced a design drawing of a catapult and exclaimed, "After I grasped the 'formulas' of mechanics that you taught me, I tried applying them to the 'Huihui Cannon' diagrams you provided, and discovered that you have indeed pushed the mechanical efficiency of catapults to its extreme!"
Liang Xiao merely smiled and nodded.
His mind was more agile than before. Although his ability to invent and create had not significantly improved, his efficiency in improving and replicating certain mechanisms was undeniable.
Ancient devices, lacking a formed theoretical and detailed calculation system, were mostly invented based on experience.
Whether it was levers, lever arms, or other mechanical aspects, ancient devices had room for improvement.
Measured in meters, for a machine to launch a stone weighing nearly two hundred jin two hundred and fifty meters versus three hundred meters, the seemingly small difference in distance was actually a vast gap.
The same device, with different techniques or details, could lead to vastly different power.
For example, the Song Dynasty's Divine Arm Crossbow was unparalleled at the time, but in the later Ming Dynasty, the Ministry of War's replicated Divine Arm Crossbow was not as powerful as described in Song Dynasty records.
The catapults improved by Liang Xiao fully utilized the principle of levers and optimized other components, their power even exceeding that of the "Huihui Cannon."
Furthermore, he commissioned the Ministry of Works to replicate Greek trebuchets, adding winches, torsion springs, and even pulleys as important torsion structures. Their actual efficiency surpassed the peak Western trebuchets he knew of. In some areas, animal grease was applied to reduce wear and corrosion, ensuring durability.
Regrettably, although these trebuchets perfectly replicated and even surpassed the power of ancient Greek trebuchets, due to being early inventions, their power and practicality were ultimately inferior to the "Huihui Cannon" that entered China from the Islamic region in the mid-14th century. Thus, they were temporarily shelved pending further improvements.
Because the Great Qian possessed its own triple-bow ballistae, these catapults did not need to launch bolts, only stones and powder kegs, which also slightly reduced their size.
Of course, the traditional catapults of the Great Qian were preserved as backups, representing a part of their civilization.
In recent years, gears, springs, and precise lever principles had become common knowledge in the Great Qian.
Zhang Yang was unusually excited today. "But compared to the Huihui Cannon, what is truly astounding is your improvement of the workshops!"
Filled with excitement, Zhang Yang simply grabbed Liang Xiao's sleeve and hurried towards the workshops affiliated with the Ministry of Works.