Chapter 131: Only Lord Ye is Worthy to Be My Master

Although skeptical, Wuguli did not make things difficult for him. He called someone over, "Wang Lin, watch this place for me for a moment. I am taking this gentleman into the valley."

Zhang Xiu bowed in gratitude, and Wuguli hurriedly returned the bow. "How could I dare accept a gentleman's courtesy? If the gentleman is truly well-versed in mathematics, he will be a teacher at the academy. When that time comes, I shall have to pay respects to the gentleman as a disciple."

"Ah?"

"My master said that people like us can also attend the lectures to learn some skills so that we can stand on our own in the future," Wuguli said.

Zhang Xiu looked at him in surprise, seeing this Kunlun slave blinking his ox-like eyes and looking ahead, his gaze filled with yearning.

Allowing family servants to study mathematics as well... This Master Ye was truly extraordinary. However, it was said that he was also proficient in mathematics; why didn't he teach his servants himself instead of recruiting an external teacher?

Zhang Xiu did not know that Ye Chang was not unwilling to teach them himself, but simply could not spare the time.

At home, he originally had many things to attend to: planning, experimenting, writing stories, and handling various interpersonal relationships. He did not have three heads and six arms, so how could he attend to everything at once? Therefore, he needed a few teachers proficient in mathematics to help him lay the foundation for the students.

Judging from the time, the sons and nephews of those wandering knights would be sent over in about ten days. Their lodgings had already been arranged in the village first; once the academy was built, they would be able to move into Wolong Valley.

Upon entering the valley, they saw the famous pavilion. The inscription *An Inscription on a Humble Room* had long since spread throughout the Central Plains, and Zhang Xiu could recite it from memory. Past this pavilion, Wuguli led him to the right, but Zhang Xiu let out an "Oh?" and ran toward the left instead.

"That is the waterwheel..." Wuguli shouted from behind. "Sir, you cannot go over there."

"I merely wish to look at the waterwheel," Zhang Xiu said stubbornly.

He stood by the waterwheel, looking at this device made of numerous wooden and iron parts, his heart stirring.

The Tang Dynasty was not without waterwheels, but this particular waterwheel made Zhang Xiu feel as though something was not quite right. Soon, he realized where the anomaly lay.

"So that's how it is..." Zhang Xiu's eyes flashed with a light of sudden realization, simultaneously mixed with awe and admiration. "Wuguli, was this waterwheel built by your master?"

"Designed by my master, and built by inviting master craftsmen."

Wuguli was somewhat sullen. The person before him, who claimed to be an applicant, was rather impolite to wander around without the master's permission. Yet he could hardly call him sneaky; it appeared that he was genuinely curious about the waterwheel.

Zhang Xiu clenched his fists and said with some excitement, "Indeed, indeed. I guessed correctly. After my paternal uncle and Lord Liang, the only one in the world who can guide me is Master Ye!"

"Sir, please come this way," Wuguli urged.

Following Wuguli to turn right, they had not walked far before they saw a sloping piece of land being leveled. In some places, the ground was being raised, and in others, it was being shaved flat, looking as though an area of about two acres was being carved out. Dozens of laborers, under the direction of craftsmen, were constructing buildings. The materials used, aside from blue bricks and red tiles, unexpectedly included cement, which was already relatively common in Chang'an but still extremely rare elsewhere.

Cement had been invented by Ye Chang, so Zhang Xiu was not surprised to see him use it here. What he did not know was that cement was currently a government monopoly. Wolong Valley was able to use it because the imperial court had established a cement kiln in Jiaozuo, originally intending to appoint Ye Chang as the imperial commissioner. Although Ye Chang had declined, he had still offered many suggestions for the cement kiln, playing a major role in site selection and process design. Now, when he wanted to use cement, purchasing some of the newly produced batches from the kiln was not a difficult task.

What interested Zhang Xiu even more was how the craftsmen on the roof were hoisting baskets of bricks and cement up.

They were not relying purely on human labor to carry them on their backs, but were using a windlass—a windlass utilizing a pulley system—which allowed the craftsmen to easily hoist hundreds of catties of weight up to the upper floor.

Others might only feel amazement, but Zhang Xiu was an insider. At a glance at this pulley system, he asked in surprise, "Could it be... that Master Ye is a descendant of the Mohist school?"

As soon as he finished speaking, he burst into involuntary laughter and shook his head: This was absolutely impossible.

The Mohist school of the Warring States period had long since been eliminated by history; even if a few remnants had been passed down, they existed only among craftsmen. Ye Chang, whose poetic fame shook the world, how could he possibly be a Mohist?

Moreover, the followers of Mohism had always been frugal and self-restraining, unwilling to overstep boundaries—the so-called followers of conventional routines. It was rumored that this Master Ye loved luxury and amusement; how did he bear even the slightest resemblance to a Mohist?

However, this discovery made Zhang Xiu look forward to meeting Ye Chang even more: perhaps only such a learned scholar could resolve the countless puzzles in his heart.

"This place is the academy. My master uses bamboo as the tendons and bones, bricks and stones as the muscles, and cement and lime as the skin and flesh. Once completed, it will accommodate more than ten teachers and over a hundred disciples," Wuguli explained when he saw him stop. "Do not look at it as unfinished now; my master said that once it is built, even the Directorate of Education will not be able to compare to it."

Zhang Xiu nodded, not feeling that Ye Chang was boasting.

There was certainly no shortage of talent within the Directorate of Education, but when it came to mathematics, those students probably could not compare to him, Zhang Xiu. Since even he had come here to seek instruction from Ye Chang, those students...

Wuguli led him onward, and beyond that was Ye Chang's residence.

Ever since Ye Chang began construction work in Wolong Valley, it had almost never stopped. His residence, after two rounds of expansion, had now taken initial shape. However, because cement had not been available at that time, his residence was still built with traditional materials, and according to his preferences, the exterior walls were coated with white lime.

Looking from afar, the snow-white courtyard walls, framed amidst a sea of golden leaves, were exceptionally refreshing and pleasant.

Zhang Xiu could not help but take a breath, and his nostrils seemed filled with the fragrance of those maple leaves.

There were originally many wild maple trees in Wolong Valley. Ye Chang had taken care to protect them, and when autumn arrived, these maple trees would begin to turn yellow, and after a little while longer, one would be able to see fire-red autumn leaves.

However, Zhang Xiu immediately realized that the fragrance did not belong to maple leaves, but rather to the scent of osmanthus flowers.

Ye Chang had transplanted a few osmanthus trees next to his residence, and he had not expected them to bloom this year. The fragrance was overpowering; in the distance it was only faint, but as one approached, it penetrated deep into the lungs.

Right beneath the osmanthus trees, a bare-chested, fierce monk with a hairy chest was laughing as he used a staff to beat a group of youths. The group of youths was driven scurrying in all directions by him, but they could not step outside the white lime circles on the ground, and thus inevitably took a few clumsy hits.

Zhang Xiu was not interested in these things; he merely felt a vague strangeness in his heart: given the atmosphere of this estate, it should have been extremely quiet, while this group of rowdy monks and youths was truly out of place with the surroundings.

"The master is here. Please wait for a moment, guest, while I go ahead and announce you—may I ask the honorable guest's full name and style?"

"My style name is Zicai, from Julu."

Zhang Xiu did not have a calling card, so Wuguli had to announce his name for him. He watched the Kunlun slave trot toward the courtyard wall and stop under one of the osmanthus trees, where several men were seated. The Kunlun slave bowed to one of them who had his back turned, and that person turned around in surprise. When Zhang Xiu saw him, he could not help being startled as well!

He looked very familiar...

Ye Chang also felt that this person looked quite familiar, but could not place him for the moment.

After he stood up, Jia Mao'er and the others nearby also walked over. These wandering knights from Chang'an were naturally inferior in martial prowess to Shi Shanzhi, so the monk had abandoned the training of the youths and followed along as well.

With a dozen or so people walking over all at once, Zhang Xiu felt immense pressure.

"The honored guest must be Young Master Zicai from Julu, who has come to apply for the position of mathematics teacher?" Ye Chang asked.

"I am indeed Zhang Zicai," Zhang Xiu bowed. "I am applying to be a mathematics teacher—and also to consult Master Ye on some matters."

"Matters?"

"Has Master Ye ever seen an armillary sphere driven by water?"

"Hmm?" Ye Chang was momentarily stunned upon hearing "armillary sphere driven by water." The name of this gadget was also very familiar; it should be... some kind of astronomical instrument.

Without waiting for his reply, Zhang Xiu continued on his own, "I observed the waterwheel built by Master Ye in the valley; the ingenuity of its mechanical operation is quite similar to that of the water-driven armillary sphere. However, such machinery has a major flaw: the iron parts at the joints are easily rusted by water, rendering them unusable afterward. The court's water-driven armillary sphere had to be put away in storage precisely for this reason..."

He spoke on his own, as if immersed in his own world. Jia Mao'er frowned slightly: This fellow is quite impolite.

At this point, Zhang Xiu changed the subject and asked again, "Has Master Ye ever obtained any lost writings of the Mohist school?"

This question left Ye Chang even more at a loss for how to reply. He blinked blankly: "Lost writings of the Mohist school?"

"Mo Di once said: *Jie* means to lift, exerting force to pull without relying on strength. The cessation of what is lifted lies in application; a rope regulates the lifting, just as when piercing it with an awl. In lifting, the long and heavy goes down, the short and light..."

After a string of words from him, Ye Chang instantly felt dizzy and his head swelled. What on earth was this *Jie*? Why did this fellow keep babbling back and forth with a bunch of nonsense about *Jie*?

Ye Chang was well-versed in classical Chinese, otherwise he could not have mixed so successfully in this era, but being well-versed in classical Chinese and being skilled in composing it were two different things, not to mention that the classical Chinese cited by this Zhang Xiu was extremely obscure. However, Zhang Xiu spoke on and on without stopping. After quite a while, he finally concluded this citation, and then continued, "I observed at the academy that Master Ye taught the craftsmen the art of pulling and lifting heavy loads. Upon reading this passage in the *Canons of Moism*, I suddenly felt enlightened. The *Canons of Moism* has only the text without diagrams; presumably, Master Ye must have obtained the lost writings of Mo Di to be able to manufacture this device..."

"Wait a moment, wait a moment. My building of the waterwheel, as well as that weight-pulling device, have nothing to do with the water-driven armillary sphere or Mozi. It was I... it was I who summarized the experience of my predecessors to create them," Ye Chang finally found an opportunity to interrupt this person.

"Is that truly so?" Zhang Xiu looked completely shocked.

"Truly."

"Indeed... Master Ye is truly a figure on par with my paternal uncle and Lord Liang!"

Zhang Xiu began talking to himself again. Seeing that he had once more immersed himself in his own world, Ye Chang rudely patted him on the shoulder, ignoring courtesy. "Since Your Excellency said you came to consult on questions, surely these aren't the only ones?"

"Naturally not. I have a question that someone asked me in the city of Chang'an: Why can Kongming lanterns rise into the sky, and why do they fall when the fire burns out?"

As soon as this question came out, coupled with the mention of "Lord Liang" just moments before, Ye Chang slapped his forehead and finally remembered this person.

This was the somewhat blockheaded fellow he had bumped into on the street with Chongniang on the day of the city competition. At that time, this guy was talking to himself, wondering why Kongming lanterns could fly into the sky. Ye Chang had casually answered him, but he had immediately followed up with several more questions. Chongniang found him annoying and pulled Ye Chang away, yet unexpectedly, in order to pursue the answers to these questions, this fellow had actually traveled hundreds of miles, chasing him all the way to Xiuwu.

"I have seen you in Chang'an," Ye Chang said.

Zhang Xiu looked Ye Chang up and down and nodded. "I also feel that Master Ye looks familiar."

He did not possess Ye Chang's memory for people, or rather, he fundamentally could not remember people unless they were quite familiar to him.

"Do not question me just yet; I have a question to ask you instead." Ye Chang was holding a folding fan in his hand, which he shook. "You keep mentioning your uncle and Lord Liang; I wonder who these two gentlemen might be?"

"My uncle is the Great Master Dahui, and Lord Liang is Master Lingzan, who was a good friend of my uncle."

"Great Master Dahui..." Ye Chang had never heard of this name; presumably, he was an obscure figure in history. As for the other, Liang Lingzan, he had a slight impression, but it was not deep. Pondering for a moment, he felt that neither of these two men was any sort of important figure, so he asked again, "These two elders of yours were proficient in the Dao of mechanics?"

"These two elders of mine were peerless in the world regarding the Dao of mechanics, though they were even more adept at celestial phenomena and calendar calculation."

Hearing this, Jia Mao'er nearby became indignant.

During this period, they had been staying in Wolong Valley, on one hand temporarily idling while waiting for the various plans proposed by Ye Chang to mature, and on the other hand to draw closer to one another emotionally. To make them even more convinced, Ye Chang had taken them to see several pieces of machinery. Therefore, in the minds of Jia Mao'er and the others, Ye Chang was a figure comparable to Lu Ban, the founding master of carpentry!

Some fellow who had popped up from nowhere, along with a monk and someone surnamed Liang, actually dared to claim supremacy in mechanics right in front of Ye Chang!

"That's just because Master Ye hasn't stepped out into the world. If Master Ye were to step out, they wouldn't be considered supreme anymore! If you're unconvinced, have them come see Master Ye's ingenious creations!"

"Both of those elders of mine have already passed away; they cannot witness Master Ye's miraculous skills. If they could see these miraculous skills of Master Ye, they would surely feel a sense of meeting a kindred spirit..."

"Are you fond of mathematics?" Seeing that this person was about to sink back into his own world, Ye Chang hurriedly interrupted with a question. "I'll pose a problem; can you solve it?"

This person claimed to be applying for the position of mathematics teacher. Although he had also admitted that this was merely an excuse to see Ye Chang, Ye Chang had no suitable candidate on hand anyway. With the mindset that being idle was being idle, he wanted to see if the man was truly capable.

In reality, Ye Chang did not hold high hopes for this person. He could tell that even if this man was proficient in mathematics, he was not proficient in teaching. He might be a research-oriented talent, but not a professorial-oriented one.

"If I can solve it, would Master Ye be willing to resolve my doubts?"

"I shall share all I know without reservation. Listen to the problem." Ye Chang posed the classic "rabbits and chickens in the same cage" problem. This problem was not overly difficult, but for an ordinary person, solving it was no easy feat.

Jia Mao'er and the others nearby began calculating on their fingers, while Zhang Xiu merely hesitated for a brief moment before instantly reporting the correct answer.

This fellow truly was well-versed in some mathematics, at least capable of holding his own in the beginning stages.

Ye Chang was secretly delighted and immediately posed a second problem. Following the principle that each problem should be harder than the last, the second problem was a water inlet and drainage problem. This kind of problem—simultaneously pumping water into a pool while draining it—had once tortured Ye Chang to the point of utter misery back in his primary school days. Bringing it out today to test someone filled him with a sense of gratification.