Chapter 41. A good night's sleep. The next day...

I slept well all night.

The next day, after getting up, Lin Fengzhi first marveled at the comfort of the Lishan hot springs, then took a soft twig from a palace maid to brush her teeth. Whenever she encountered inconveniences in life, Lin Fengzhi missed modern times even more.

Then I made up my mind to change.

As she brushed her teeth, she thought, "Toothbrushes are easy to make; you can make simple toothbrushes with pig bristles or horsehair."

Toothpaste is a bit of a hassle, but it can be made. It's simply a matter of mixing salt, wood ash, tea leaves, and honey in a certain proportion.

The real challenge is corrosion prevention.

Natural recipes are prone to spoilage and cannot be stored for long periods.

Lin Fengzhi took the cloth and wiped her face, then went to find the Mo family disciples with renewed energy.

Su Shaofu's words yesterday reminded her that the gunpowder she had made before was actually not very stable and its lethality was only so-so. It was far from enough to be used on the battlefield.

When she arrived, the disciples of the Mohist and Agriculturalist schools were on high alert.

Besides the people she brought, there was also the astrologer from last night and some guards that the First Emperor had assigned to her.

"Good morning, everyone." Lin Fengzhi sat down and instantly got into work mode: "Shengkuan, do you remember the gunpowder I used at Xiangjun Temple?"

Sheng Kuan nodded slightly, of course he remembered. Initially, he stayed in the land of the Ke Luo people because Lin Fengzhi had promised to tell him the secret. Later, when they were making fireworks, he told him the secret and even got him to join the fireworks-making team.

Shengkuan still remembers adding pine soot, raw soapberry, sesame oil, and lead powder* to it, and then colorful fireworks bloomed in the sky.

He still remembers how he felt at the time—unbelievable, his soul pounding.

The deafening roars, the dazzling lights, the vibrant and fantastical colors, the pungent smell of sulfur, and even the sensation of being burned by sparks on the skin when not paying attention—all these scenes are still vivid in my mind.

"The formulas at that time were rather crude, making them difficult to transport and preserve for a long time. Now that the war between the Baiyue people in the south is about to break out, the First Emperor wants to build the Lingqu Canal to connect the Xiangjiang River and the Lijiang River to ensure the transportation of grain. If gunpowder is available, not only might the war end sooner, but the manpower required for the Lingqu Canal will also be reduced."

Xiangli Liang raised his eyebrows and looked at Shengkuan with an ambiguous expression, as if to say, "Is this the person you admire?"

What's the difference between this and their Xianglimo?

Sheng Kuan didn't notice, as he listened intently to Lin Fengzhi's explanation of what needed to be done to improve stability.

Saltpeter refining, charcoal selection and control, sulfur purification, followed by iterative updates to the formula. The old formula of one part saltpeter, two parts sulfur, and three parts charcoal is outdated. Only when saltpeter accounts for 70% can the explosion speed be significantly improved.

"The manufacture of gunpowder is extremely dangerous, so we must pay attention to safety," Lin Fengzhi said.

Seungkwan nodded.

Lin Fengzhi then took out a roll of cloth, on which was a drawing of a curved plow she had recently created.

Yes, she wanted to improve farm tools.

During the Qin Dynasty, the main agricultural tools used were straight-shafted plows or more primitive hoes. These tools were simple in structure, required two oxen to pull, were difficult to turn, and lacked the ability to adjust the plowing depth. Although iron agricultural tools had become widespread in many areas during the Qin Dynasty, plows still had a simple structure.

She thought that if she could change the farming tools, perhaps she could improve production efficiency and thus increase production, just like she had done in the land of the Kolo people.

Seeing that it was related to farm tools, Xu Chu also came over. After looking at it for a while, he asked, "Hey, this thing seems to only require one person and one ox to turn the plow."

As expected of a disciple of a farming family who has the deepest experience dealing with farmland, Lin Fengzhi gave him an approving look.

Xu Chu pointed to an unclear part of the map: "What is this for?"

The place Xu Chu was referring to was the plowing and plowing construction part of the curved plow.

"These are wedge-shaped wooden blocks used to adjust the tillage depth, somewhat similar to the mechanical techniques of the Mohist school."

"The bending of the shaft like a bow is also a kind of Mohist mechanical art?"

Qin Dynasty carpentry primarily used straight wood, and the technique of bending wood was not yet mature, so it's no wonder he asked that question.

"I guess so," Lin Fengzhi said, since she could do it anyway.

Xiangli Liang glanced at Shengkuan silently again. How many surprises does Chu Mo have that he doesn't know about?

Xu Chu suddenly frowned. He pointed to the slender curved shaft of the curved plow: "The divine messenger probably has never plowed a field himself. This part will definitely break due to the lateral torque when plowing deeply. Moreover, it seems to use much more iron than a straight plow. Ordinary people probably can't afford it."

"The most important things about plowing are breaking up hard soil and saving effort. This curved plow is too light. If we actually use it, it might easily drift and the plowshare tip might slip off the ground, which would be counterproductive."

Lin Fengzhi scratched her head. She had never actually farmed before, nor had she thought about it that deeply. In her mind, the curved-shaft plow could replace two oxen with one, significantly lowering the threshold for agricultural production. It had been used for thousands of years since its development in the Tang Dynasty. Didn't that prove its universality?

Her intentions were certainly good, but she was detached from reality and made some assumptions.

It was through Xu Chu's questioning that she slowly remembered that the curved-shaft plow was also known as the Jiangdong plow. It was indeed a pinnacle of agricultural tool reform in the Tang Dynasty, but it was suited for paddy fields in the south, not dry land in the north. It was a model of how immigrants from Jiangnan adapted northern plows for rice cultivation.

In the south, paddy fields are moist and heavy, and the curved plowshare effectively overturns clods of soil, forming a muddy layer in the paddy field. In the north, the main agricultural areas are in the Yellow River basin, where the soil is mostly loose loess, requiring deeper plowing rather than simply turning the soil. In dry soil, the curved plowshare's turning function creates excessive resistance, actually reducing efficiency.

Furthermore, in the fragmented paddy fields of the south, the short, curved shaft of the curved plow, combined with its flexible plowshare, allows for quick maneuvering between field ridges. In contrast, the continuous, long plains of the north require a straight-shaft plow for more efficient deep plowing.

History has also proven the failure of the curved plow to be promoted in the north.

During the Tang Dynasty, the imperial court promoted the curved plow in Luoyang, but "most people abandoned it and went back to using the old plows." The reason for this was that "the soil was dry and the shafts broke, and the oxen could not keep up with the load."

Wang Zhen of the Yuan Dynasty recorded in his book "Agricultural Treatise" that the north tried to add double yokes to the curved plow, but the imbalance of torque caused the plow to fall and injure the oxen, so the plow was eventually replaced by the straight plow.

In conclusion, as the Book of Agriculture states, there are different types of plows in the north and south, and different tools are suitable for different regions; forcing them together will only harm both.

While Lin Fengzhi was pondering, Xu Chu and the others were not idle either. They discussed the advantages and suitable locations of the curved plow, while the Mo family members also silently discussed whether they could reproduce the curved plow.

“You’re right. Curved-shaft plows are indeed not as adaptable to the vast plains and dry lands of the north as straight-shaft plows.” Lin Fengzhi secretly reminded himself that he couldn’t just take out something from a different era without considering whether it was compatible with the Qin Dynasty and whether it could improve the Qin Dynasty’s productivity.

Take the curved plow for example. Can it improve productivity now? Of course it can, but the economic, political, and even agricultural center is currently in the north. The curved plow she introduced will only be able to reach its maximum effect after the economic center shifts south.

What happened before is one thing, but we must be very careful about what we bring out next.

Therefore, Lin Fengzhi temporarily put aside her long-cherished idea of ​​cement.

“I didn’t consider the differences between the north and the south. The curved plow is more suitable for cultivating paddy fields in the south. Just like the fields in our Keluo people’s land are very suitable for the curved plow.” Lin Fengzhi admitted his mistake and said, “Then, based on the development of the curved plow, we will try to improve the straight plow we are currently using so that the people can harvest more grain.”

Xiangli Liang had lived in the Qin state for a long time, had seen the common people tilling the fields, and had even worked in the fields himself. Upon seeing the blueprints for the curved-shaft plow, a brilliant idea struck him: "If we make the shaft of the straight-shaft plow slightly curved, and add the movable plowshare of the curved-shaft plow, wouldn't that improve the flexibility of the straight-shaft plow?"

Lin Fengzhi stroked his chin and looked at it, already sketching out the image of the improved straight-shaft plow in his mind: "That's good, that's good. A straight-shaft plow requires two oxen to pull it. If we shorten the shaft length and reduce the weight, wouldn't one ox be enough to pull it?"

The others also shared their opinions.

"The curved plowshare has a circular plowshare above the plowshare, which is not suitable for the dry land in the north. What if it were made into an arc shape?"

"And this plowshare tip. The original plowshare tip of the straight-shaft plow had a large angle, which made it easy to wear down when facing hard soil. If it were made with a smaller angle and thickened, the lifespan of this piece of wrought iron would be extended. Wouldn't that reduce the burden on the common people?"

“And here,” Sheng Kuan pointed to the traction point on the curved plow: “We can use this to distribute the pressure on the ox’s shoulders.”

As Lin Fengzhi listened, he summarized: "In other words, we should still retain the main structure of the straight-shaft plow, with lightweight shaft, low-resistance traction, and enhanced soil breaking as the core."

She drew the improved straight-shaft plow design again on the cloth, adjusting it as she drew: "Done."

"Whether it's the curved-shaft plow or the improved straight-shaft plow, I want them both. The Qin territory is vast. If the south uses the curved-shaft plow and the north uses the improved straight-shaft plow, then the capital of Guizhou will have a bright future. This is just a preliminary design. We will revise it if there are any unreasonable or erroneous parts during the production process. This matter will be handled by Master Xiangli. If you need any manpower or materials, just let us know."

Xiangli Liang gave her a deep look, then immediately accepted the order: "Yes."

With the issue of farm tools settled, she summoned Xu Chu and other disciples of the farming school and asked a seemingly unrelated question: "Having stayed in the land of the Keluo people for so long, do you find the noodles delicious?"

Xu Chu was taken aback, recalling the chewy texture of the noodles and the soft texture of the steamed buns and mantou. He swallowed hard and said, "They are truly a delicacy."

"Then why, after harvesting millet and sorghum along the way from Xiangshan, has no one planted winter wheat?"

As early as the Warring States period, some people in the Guanzhong region began to cultivate winter wheat, but it was not yet widespread. Large-scale cultivation of winter wheat did not begin until the reign of Emperor Wu of the Western Han Dynasty.

Why?

Xu Chu replied, “Divine messenger, we like to eat wheat in the land of the Keluo people because we have stone mills to grind it into flour, which is then used to make other delicacies. Later, there were even water-powered millstones to grind wheat. But in Guanzhong, there are not so many stone mills. Wheat porridge is hard to swallow, and unless you are a poor person, no one would want to eat wheat porridge.”

“There’s no need to worry about the stone mill. I’m only worried about whether there are enough wheat seeds, whether they are good enough, and whether they can survive the winter. If we can really plant winter wheat, after harvesting millet and sorghum, there will be hope for the lean season.”

Everyone present was deeply moved, even the guards were touched.

“Alright.” Xu Chu gritted his teeth. “If the people who plant winter wheat can gain some benefit, I think they will be even more willing to do it. They will also have more wheat varieties to choose from next year. What do you think, Divine Messenger?”

Lin Fengzhi nodded and said, "I will discuss it with His Majesty."

She felt it wasn't a big problem. Back in the clan, when did the First Emperor not eat some noodles every day? Besides, planting winter wheat would ultimately enrich his national treasury. She didn't even dare to imagine how much tax revenue could be collected after large-scale promotion.

With a wider variety of food options, more people were able to survive.

The advantages outweigh the disadvantages.

It's obvious what choice the First Emperor would make.

-----------------------

Author's Note: *The recipe for five-colored smoke in the "Treatise on Military Preparedness"

I originally intended to go straight to the curved-shaft plow, but the more I researched, the less it seemed to fit the bill. Curved-shaft plows are less suitable for use in the north; what follows is a description of the straight-shaft plow, an improvement from the Ming and Qing dynasties—the Shandong "Chuang plow."