In the eleventh month, Chang'an saw its first light snowfall.
A young man wrapped his clothes tighter as he stepped through the gates of the Imperial Academy. He watched as a gust of cold wind spun across the ground, lifting a scattering of fine snow.
The sight made him hesitate. He chose to take the covered corridors instead, avoiding the wind and snow.
The Imperial Academy was no longer as empty as it had been when Lord Xuande first arrived in Chang'an.
Craftsmen, students, and even common people who came during the farming off season to ask about new farming or cold weather methods now packed the renovated academy to the brim.
The youth moved through the crowd, noticing those who paid no attention to the falling snow and chatted easily in the cold wind. These were mostly locals from Yong, Liang, and the Guanzhong region.
In contrast were people like himself. Some stretched out their hands under the corridors to catch snow curiously. Others walked back and forth in the courtyards, listening to the crunch of thin snow under their shoes. These were mostly people from Yi Province.
But according to his Guanzhong friends, when December came, the snow could be several times heavier. He wondered what kind of scene that would be.
And before the heavy snow arrived, how many coal briquettes could Chang'an store?
With these calculations turning in his mind, he passed through two corridors and finally turned into a side hall. The cold wind was cut off behind him.
The dim interior made him frown slightly. After setting down the letter in his hand, the first thing he did was trim the lamp wick. The darkness was instantly driven away.
The change in light brought Lu Su out of his focused calculations. He looked up and smiled.
"Hudu, you came at just the right time. Help me see if this method for solving the chicken and rabbit problem is correct."
Hudu turned back with a smile.
"Master Lu, this problem is not difficult. And now with the bead abacus to assist, how could it be wrong?"
"Oh right. My grandfather has decided to restore my original surname of Ma. He gave me the name Zhong, and the courtesy name Dexin, to remind me never to forget Lord Xuande's kindness and to take loyalty as the foundation of my conduct."
As he spoke, Hudu, now Ma Zhong, placed the letter he brought in front of Lu Su.
"Master Lu, the reply from Shang Commandery should be the news from the matter we inquired about half a year ago."
Lu Su's face lit up. He opened the letter while speaking.
"Ma Zhong, Ma Dexin. A good name and style. Your grandfather's thinking must be for the sake of the imperial examination."
Ma Zhong nodded.
"To sit for the examination is both my wish and my grandfather's wish. If Lord Xuande uses me in the future, changing my name then would be troublesome, so we changed it now."
Lu Su understood, though he felt he had heard this name from Pang Tong before.
His hand trembled slightly as he unfolded the letter. Reading by the lamplight, he sighed lightly.
"If only we had electric lamps. Wait."
"Du You County has mountains producing coal."
"And Shang Commandery also says that open air coal stretches for more than ten li, all easy to pick up from the ground."
Ma Zhong had still been wondering what Doctor Lu meant by electric lamps when the suddenly raised voice startled him.
Master Lu's face was filled with wild joy, with none of his usual refined Jiangnan gentleman demeanor.
Ma Zhong could understand why.
At present, most of Chang'an's coal briquettes came from Jiang Province mining, processed in Chengdu, and transported through Hanzhong. Another portion came sporadically from Hanzhong, Yong, and Liang.
In Yi Province, coal had been used for fires, iron smelting, sugar boiling, and paper pulp.
After Lord Xuande used it for military purposes and achieved victory in the Wei River valleys, coal's role in cold resistance had become more prominent than ever.
As far as Ma Zhong knew, after entering Chang'an, Lord Xuande had been continuously sending people to search for coal producing areas in Guanzhong.
According to Zhuge Liang, before Dong Zhuo moved the Son of Heaven west to Chang'an, the Small Treasury Office in Luoyang had used coal, but it all came from Shanyang and similar places. Guanzhong itself had none to rely on.
"Where is Du You County?" Ma Zhong asked curiously.
Lu Su was energized.
"Only one hundred and fifty li north of Chang'an."
Ma Zhong grew happy as well. One hundred and fifty li meant that after this winter, Chang'an could be self sufficient in coal from next year onward.
Could Chang'an become as prosperous as Chengdu?
"And Shang Commandery?" Ma Zhong asked.
Lu Su's joy faded slightly.
"That is over a thousand li north of Chang'an."
That meant it could not be relied on for now. Perhaps it could be left for descendants.
Lu Su thought for a moment.
"Dexin, trouble you to deliver this letter to Military Advisor Zhuge."
Ma Zhong accepted the task and left.
Though not yet capped, he was sharp minded and had studied at the small academy in Chengdu, making him a student of Master Kongming. His family was poor, so when Chang'an was first stabilized and the academy lacked manpower, he took a job and was now valued by Lu Su.
As for coal exploration, the academy had earlier sent people to accompany the efforts, so now replies were being sent back.
A strand of cold wind slipped in through the door crack as Ma Zhong left. It collided with the lamp flame, causing light and shadow to sway, making Lu Su pause.
He still remembered how at this time last year, he had been anxious over Lord Sun's sudden and unpredictable actions.
Now as year end approached again, what filled his chest and mind was completely different from the past forty years.
As for matters in Jiangdong, he had long since had no energy to care.
For the first time in four hundred years of Han, a formal imperial examination was about to be implemented by his own hands.
Lord Xuande hoped to use this system as a powerful response to Cao's call for talent.
Kongming hoped to use the examination as a blade to suppress powerful clans and raise humble families, trying a path completely different from later history.
As for himself, Lu Su shook his head and laughed inwardly at how much he was thinking.
He stretched, adjusted the lamp wick again, and returned to his studies.
One hand held the mathematical classic. One hand worked the bead abacus. Beside him lay Kongming's annotations on the classic.
Lu Su once again immersed himself in learning.
From July until now, Lu Su had been in a constant state of cramming.
What he valued most was mathematics, honored by later generations as the king of sciences.
Though few in the realm specialized in mathematics, Lord Xuande, Kongming, and Lu Su were all determined to establish a mathematics examination.
With that, how to design the test questions became a problem. Fortunately, Lu Su was gradually forming a plan.
Ma Zhong, carrying the letter returned by Doctor Lu, passed through several corridors and arrived at the eastern side of the Imperial Academy. Guards were stationed here, and ordinary students could not approach.
Only after verifying his token was he allowed through.
As soon as he entered the courtyard, Ma Zhong saw a strange lantern slowly rising from the courtyard ahead. With no ropes or pulling, it floated into the air and continued to rise.
He could hear discussions from nearby courtyards, filled with surprise. Even the guard who had checked his token could not help but stop to watch.
But Ma Zhong remembered what Master Kongming had said.
Distinguish the object. Analyze its principles. Follow the principles and apply them. From this, one can infer others.
So he immediately suppressed any supernatural thoughts and instead grew curious about the underlying principle.
Entering the courtyard, he saw Master Kongming standing with his hands behind his back, together with Master Pang Tong, both looking up at the strange lantern flying farther and farther away.
Kongming was approachable by nature, so Ma Zhong asked directly.
"Master, what is the principle behind this Kongming lantern?"
To Ma Zhong's confusion, this simple question caused the two masters to react differently.
Master Kongming looked helpless. Master Pang smiled slyly.
"Hudu, why do you think this lantern is called a Kongming lantern?"
Ma Zhong looked Pang Tong over.
"Since it was made by Master Kongming, naturally it is called a Kongming lantern."
Pang Tong's smile stiffened. He flicked his sleeve, clearly displeased.
Why assume I cannot make it?
Ma Zhong paid no attention to that and explained his name change.
Kongming's expression softened, and he offered some words of encouragement.
As for the principle behind the lantern rising, Kongming admitted he did not know the specifics. He could only roughly mention thermodynamics, a field he only knew by name.
Their casual talk ended as the lantern, now high in the sky, was hit by a strong wind, flipped, spun, and disappeared to an unknown place.
Only then did Ma Zhong remember.
"Master, master Lu sent me."
"Is it news of coal in the mountains of Du You County?" Kongming asked.
Ma Zhong nodded.
"Lord Xuande already knows as well. Starting next February, the matter of Du You coal works will be discussed."
Ma Zhong blinked and said he would return to tell Doctor Lu not to worry.
Watching the uncapped youth leave, Pang Tong said quietly.
"This is the Ma Zhong listed among the fourteen civil officials?"
Kongming nodded, smiling.
"Judging by his birthplace, age, and talent, he is likely the true Ma Zhong. This child will surely stand out in the examinations."
"I wonder what it will be like when he meets Lord Xuande."
Pang Tong grinned broadly.
"That scene will be a wonder to behold. I truly wish to see it with my own eyes."
The lack of talent under Lord Xuande was no secret.
What later generations said casually might contain insights from small signs.
Thus, Kongming and the others often reread the light screen notes in their spare time, searching for subtle hints of talent or hidden meaning.
What they first dug out was not hidden meaning, but Ma Zhong himself.
According to later generations, this Ma Zhong could win Lord Xuande's praise, assist Zhuge Liang in governing Nanzhong, participate alone in major policy decisions, stabilize Chengdu amid internal and external troubles, and ultimately earn a reputation for virtue.
But what about the Ma Zhong from Jiangdong?
He fought bravely in Nanzhong and later supported Nanjun, killing Pan Zhang. His martial merit was outstanding.
As for literary talent, Lord Xuande once ordered him to write an essay. After seven days, he produced six characters, five of them wrong.
No matter how one looked at it, that did not match virtue.
Later records also stated that after General Yun Chang was defeated at Maicheng, the general who captured and killed him was also named Ma Zhong. At the time, Kongming and Pang Tong suspected it was just a shared name.
Now that guess was completely confirmed.
Seeing Pang Tong's expression, Kongming did not comment further. He also had no intention of telling Lord Xuande.
Let this child make his name through the examinations.
The two stood in the falling snow, set aside the amusing matter of Ma Zhong, and began discussing how to improve the use of coal from Du You County.
At such times, they could not help but envy that "Second Phoenix Emperor."
From the thousand year climate change charts, it was clear. Their current era was the opposite of early Tang.
In the flourishing Tang, the climate was so warm that rice could be grown as far north as Zhuozhou.
In this chaotic era, in just a few more years, even rice in Jiangdong might have poor harvests.
As cold days grew longer, to prevent and resist barbarian incursions from the south, they first had to solve heating for soldiers and common people. That meant coal.
"Chang'an to Du You is only one hundred and fifty li. We can build a full road between them, pave it with cement, add rail transport, and make it Chang'an's lifeline. How about it?" Pang Tong said.
"Agreed," Kongming replied.
"As for Shang Commandery," Pang Tong hesitated.
It was over a thousand li from Chang'an. Cement and rails could not solve that distance.
"To speak of taking Shang Commandery's mines is too early. We must first take Hedong, recover Taiyuan and Xihe, then look north to Dingxiang and Yuncheng, and perhaps recover Shuofang and Wuyuan."
As he spoke, even Pang Tong felt it was hard to continue.
Anyone familiar with Former Han history would know Shang Commandery well, because north of it lay the famous Shuofang and Wuyuan Commanderies.
Both were established personally by Emperor Wu, to lock the Hetao firmly to Han.
But the distance was too great, draining Emperor Wu's reign, and the Hetao defense never reached his original expectations.
The high cost was simple. Though directly north of Chang'an, mountains blocked the way. One had to detour through Hedong, pass Yanmen and Dingxiang, before reaching it.
Still, Emperor Wu's efforts were not entirely in vain. At least the Han people there were very good fighters. Lü Bu and Zhang Liao were examples.
Many thoughts flashed through Pang Tong's mind.
In the end, Kongming responded with a single word.
"Good."
Seeing Pang Tong's surprise, Kongming said softly.
"From the reply, Shang Commandery's coal is vast beyond measure. If we can destroy Cao and restore Emperor Wu's plans, Shang coal can be sent nearby to Hedong, and then protect Hebei from severe cold."
Pang Tong nodded. The logic held.
But he also knew that though Kongming spoke lightly, execution would require countless plans, eventually forming a massive project to defy climate and end chaos.
But was that not exactly what they wished to do?
Just then, a shout came from the nearby room.
"Steamed garlic, distilled essence, it is done."
Kongming and Pang Tong's spirits lifted at once. They hurried over.
The lantern Ma Zhong saw had only been a way to pass time while waiting.
The real goal was to see what effect garlic essence would have.
Earlier, during exchanges with Tang's Small Treasury on the light screen, though the other side did not know the exact method of distillation, they still offered many useful ideas.
In the end, Kongming, Pang Tong, and Zhang Zhongjing worked without sleep for a full day and night to draft a crude distillation device.
Then they had craftsmen fire and assemble it, finally completing it yesterday.
Early this morning, the two came here to find Divine Physician Zhang already busy with his disciples.
Unable to help, they made a lantern and discussed upcoming major matters.
At last, there was a result.
Zhang Zhongjing came out, exhaustion impossible to hide.
But the old physician ignored everything else. He carefully raised a transparent glass bottle, staring intently at the pale yellow liquid inside, eyes filled with awe.
"The miraculous medicine of later generations is finally complete."