Mercury pills were useless effort.
Gunpowder, however, would be of great use for generations to come.
Kongming felt that the Daoists' conclusion was not entirely wrong.
After all, in later ages, it was precisely this "Pill of Great Destruction" that propelled man-made creations into the sky, allowing humanity to glimpse heaven and earth, and to understand the sun and moon.
That said, the Daoists clearly needed a warning.
Otherwise, before they ever witnessed the true applications of gunpowder, they might very well achieve a premature "daylight ascension" by blowing themselves apart.
Leaving the Daoists to their heated arguments, Kongming wandered aside and noticed their previous pill formula still written out:
Saltpeter, three parts.
Red sugar, three parts.
Realgar, one part.
Pound finely, grind thoroughly, mix evenly to form a pill.
The Daoists really were… keeping up with the times.
Kongming couldn't help but admire them.
Cane sugar had only been successfully produced in Shu for half a year, and already the Daoists were using it in alchemy without the slightest hesitation.
Sugar production required vast quantities of sugarcane. Previously, Shu had grown enough for consumption, but nowhere near enough for refining, which kept prices extremely high.
Although Kongming had already arranged for expanded planting, the first full harvest would not arrive until autumn.
Thinking from another angle, however, made Kongming press a hand to his forehead and sigh.
So… you really don't have a single reliable pill formula, do you?
In that case, this "smoke pill" formula would be recorded for now. They could continue experimenting once sugar was no longer scarce.
After writing down his notes, Kongming quietly closed the door for them as he left.
The Chengdu government offices had changed greatly since Liu Zhang's time.
Even after Liu Bei brought his two wives to Chengdu, they could occupy only three or five rooms at most.
The empty palace halls were therefore requisitioned for various purposes.
Some were used by Daoists for alchemy.
Some by craftsmen experimenting with glass.
And some for Zhang Song's unusually enthusiastic project—the "Little Imperial Academy."
Kongming had not yet brought his family to Chengdu.
Publicly, his wife was already overseeing multiple engineering workshops in Gong'an County, promoting craftsmanship and advancing applied engineering at a rapid pace.
Privately, Kongming wanted to see her accomplish something of her own.
Especially after learning of "Chen Baoguang's wife," that desire had only grown stronger.
Within the government offices, Kongming now possessed a heavily guarded workshop of his own.
Inside were scattered countless miniature models, blueprints, and partial images taken from the light screen—fragments of a work later generations would call Dream Pool Essays.
The most striking object hung at the center of the room.
A massive spherical diagram.
Upon it, written personally by Kongming with solemn reverence, were two characters:
Earth.
At this moment, Kongming stood staring at the globe, deep in thought about the nature of chemistry.
The method of making alkali from plant ash—dismissed by the light screen as "lunatic behavior"—was, in truth, not complicated at all.
Burn plant matter into ash.
Boil the ash with water.
Filter it through silk cloth.
Let it sit overnight.
Collect the clear liquid on top—this was alkaline water.
It looked little different from river water.
Yet porridge cooked with it became thicker.
Clothes washed with it grew softer.
Paper pulp treated with it turned whiter.
Mysterious effects.
But why?
Lost in thought, Kongming returned to his desk and wrote three characters on the page:
Plant Ash
Below them, he wrote:
Fertilizing Fields
Since the pre-Qin era, plant ash had been used to enrich farmland. But depending on region, the required amounts varied greatly.
After a moment's consideration, Kongming recorded what he knew:
Hedong Commandery: no plant ash used.
Pingyuan Commandery: nine he per mu.
Nanyang Commandery: one dou per mu.
Wuling Commandery: half a hu per mu.
Half a hu equaled five dou.
Five dou equaled fifty sheng.
Fifty sheng equaled five hundred he.
From this, Kongming wrote his observation:
From north to south, the fertilizing effect of plant ash increases steadily.
After pausing, he added another line:
From alkali extraction methods, it is known that plant ash is rich in alkali.
He thought carefully, ensuring nothing was missing.
Then, with deliberate care, he wrote his conclusion:
Northern soils may be alkali-rich. Southern soils may lack alkali.
Below that, he added his speculation:
Oranges differ north and south of the Huai River—could alkali content be the cause?
Bamboo is rare in the north, chives rare in the south—might this also be related?
Exhaling slowly, Kongming looked over the page.
For the first time, he felt a faint thrill—something later generations would call science.
Differences in land were not changed by imperial will.
They were not altered by decrees backed by Heaven's authority.
They were inferred through knowledge, learning, observation.
One identified shared traits.
One analyzed differences.
One tested hypotheses.
Perhaps, one day, principles could be established—rules future generations might follow for a thousand years.
The April night wind still carried a trace of chill.
Yet Kongming felt faintly overheated.
Only after walking beneath the moon in the courtyard did he finally return to sleep, still dressed.
The next morning, he was dragged out of bed by an ecstatic Liu Bei.
"Kongming! Yuanzhi's boat has arrived in Qianwei County!"
Qianwei lay only one hundred and forty li south of Chengdu.
Still groggy from staying up late, Kongming needed a moment to process it.
Ah—so Yuanzhi must have traveled upstream by boat, passing Jiangzhou, Jiangyang, and Wuyang, entering Shu by water.
Spring and summer in Yi Province brought steady southeast winds, making river travel from Jingzhou particularly convenient.
By the time Kongming fully came to his senses, he was already standing with Liu Bei at the southern gate of Chengdu.
Liu Bei could not stand still.
He paced restlessly, stopping again and again to stand on tiptoe and peer southward, as though sheer will might summon the boat into view.
Kongming called over Chen Dao's attendant, splashed water onto his face, and suggested:
"If my lord is this anxious, why not ride out to welcome him?"
Kongming soon regretted this suggestion.
Liu Bei immediately agreed—and dragged Kongming with him.
Ten li south of the city… still not enough.
They pushed another twenty li, until the riverside path grew too narrow for horses.
Only then did Liu Bei stop.
The bumpy ride had fully awakened Kongming.
Looking at Liu Bei, he joked:
"Why not level the mountain ahead, my lord? It blocks your view of Yuanzhi."
Liu Bei laughed without embarrassment.
"Since hearing he would return, I have tossed and turned every night."
"I've waited a full month—how could I fret over a mere moment?"
Kongming laughed, unconvinced.
If that were true, why ride thirty li until the road ended?
Soon enough, a small boat emerged from behind a distant hill.
From horseback, Kongming could see a thin scholar at the bow, robes fluttering, bowing repeatedly northward.
Beside him, Liu Bei could restrain himself no longer.
"Yuanzhi!"
"I'm here, Yuanzhi!"
Dense riverside trees obscured the shore. The boat did not slow or turn.
Panicked, Liu Bei urged his horse into the shallow water, calling out desperately.
This startled Kongming and the guards alike.
Several attendants rushed forward, grabbing the reins to pull the horse back.
As the horse turned, Liu Bei twisted around and shouted again:
"Yuanzhi—!"
At last, the commotion drew attention.
The scholar at the bow began shouting back, pacing anxiously.
The boat slowed and angled toward shore.
As soon as it reached the shallows, Xu Shu did not hesitate.
He sprinted and leapt from the boat.
Liu Bei cried out and jumped down as well, stretching out an arm to haul Xu Shu ashore.
Their hands clasped tightly.
Seeing Xu Shu soaked, bowing, shoes caked with mud, Liu Bei said softly:
"Yuanzhi, why risk yourself so? Chengdu lies but thirty li away—soon reached. You must cherish your life."
Xu Shu studied Liu Bei closely.
His eyes held a thousand unspoken words.
At last, he bowed.
"My lord—Xu Shu has returned."
"Good! Good!"
Liu Bei responded eagerly, patting Xu Shu's shoulder.
"Your return is enough."
Stepping back, Liu Bei looked him over again, then clasped his hand joyfully.
"With Yuanzhi back, we may devote ourselves wholly to restoring the Han. I have no regrets left."
Hand in hand, clothes soaked, feet sunk in foul mud, the two spoke cheerfully as though nothing mattered.
Liu Bei recounted recent victories with enthusiasm.
Xu Shu listened, smiling quietly.
He, too, spoke of what he had seen traveling south from Xuchang.
Only after Liu Bei helped him onto a horse did the former Yingchuan wanderer finally turn and call out:
"Had I known the name of Zhuge Wuhou earlier, I would have dragged Kongming from his thatched hut alongside me!"
Watching Liu Bei mount behind Xu Shu, sharing the horse, Kongming clasped his fan and bowed.
"To revive the Han—now is still not too late."
The old friends exchanged smiles.
The return to Chengdu was far more relaxed.
The three rode slowly, chatting.
"Is Shiyuan in Chengdu?" Xu Shu asked.
"He oversees military affairs in Hanzhong," Kongming replied.
"Yong and Liang are fragile as eggs; Guanzhong stirs. He cannot leave."
"Should Cao seize Yong-Liang, he links Guanzhong and seals Hanzhong.
If we secure them instead, Chang'an becomes untenable—Cao would be forced back to Tong Pass.
Hanzhong truly cannot spare Shiyuan."
"Well… not necessarily," Kongming said lightly.
"My lord has recently gained a new strategist in Chengdu—Fa Zheng. He has a roaming knight's temperament and could also command Hanzhong."
"Oh?" Xu Shu's eyes lit up. "I must meet him someday!"
"Cough."
Kongming changed the subject.
"I heard Guangyuan intends to settle in Jiangling?"
Xu Shu sighed.
"Guangyuan is not Cao's man, nor does he wish to serve our lord. He has treated me with loyalty—I cannot force him."
"When he escorted me to Yi Province, he said he would seek employment in Jiangling. We'll see what the future brings."
Kongming nodded.
Everyone chooses their own path.
Xu Shu then smiled, remembering something.
"The physician Zhang on our boat complained bitterly about you."
"Oh?"
"He says you clearly understand medicine, yet always speak vaguely, forcing him to research principles himself. Quite rude, apparently."
Kongming froze—then burst out laughing.
"Good that he's come," he said.
"These mountains are rich in herbs. A blessed land for a physician."
As they talked and laughed, Chengdu came into view.
Kongming spotted Lady Wu standing quietly by the roadside and smiled.
"To accept or refuse—my lord should decide soon."
Xu Shu noticed her as well.
"And she is…?"
Seeing Liu Bei's faint embarrassment, Kongming smiled behind his fan.
"She is a daughter of the great Wu clan of Chengdu. A physiognomist once foretold she bore the mark of great nobility."
Xu Shu laughed heartily.
"If we speak of great nobility—there is none greater than my lord!"