The design drawings have been drawn, and the craftsmen have prepared the materials. Li Guodong also explained the craftsmen in detail about the explanation. After that, the craftsmen began to work and built a new blast furnace in a newly built brick and tile house based on Li Guodong's design drawings and explanations.

The craftsmen were building blast furnaces, and Li Guodong didn't have to do anything during this period. He had finished guiding the places he needed to guide, so he walked out of the valley and went to the farmland outside. Because when he first came to Kinmen Island, he found that all the farmlands planted here were sweet potatoes.

"Uncle, why do you grow all sweet potatoes on Kinmen Island?" Li Guodong called an old farmer and bowed respectfully and asked in Minnan dialect. His previous life was from Quanzhou, so he naturally spoke Minnan dialect.

The old farmer looked at Li Guodong and saw him wearing silk clothes, square scarf, and jade signs hanging around his waist. So the old farmer quickly returned the gift: "Young master, don't be too polite, I can't afford it. If you don't plant all sweet potatoes on Kinmen Island, how can you afford to raise more than 10,000 Zheng family officers and soldiers? There are few lands and many people. Not to mention Kinmen Island, Xiamen Island and Zhangzhou beaches are the same. The yield of sweet potatoes is high, so everyone grows sweet potatoes."

Li Guodong remembered the later King of Lu Zhu Yihai, who was known as the King of Sweet Potato Vanguard because when he lived on Kinmen Island, his daily staple food was sweet potatoes.

"Uncle, do you have any sweet potatoes harvested? I came from the north and want to see this thing." Li Guodong asked again.

"Young Master comes from the north, why do you speak Minnan dialect so well?"

"I came with General Zheng and learned some Minnan dialect from him."

"Please come with me, young master."

The old farmer brought Li Guodong to his house. It was a typical Minnan-style building with red bricks and red tiles and swallowtail gables. It can be seen that the old farmer's family's conditions are pretty good. Seeing Li Guodong staring at his home in a daze, the old farmer smiled and explained: "Young master, there are few farmers on Kinmen Island, and one of the old sons is also in the army of the Zheng family. The old couple farmed, and the sweet potato yield is high. The two sons went to sea to fish. There is no need to pay taxes to the court here. Just sell the grain to the Zheng family. Although the purchase price is not high, the yield is very high, so life is pretty good."

After chatting with the old farmer, Li Guodong realized that the old farmer had escaped from Quanzhou. When he came to Kinmen Island, he did not have to pay taxes to the court. The minor officials in the Quanzhou Prefectural Office did not have the courage to come here to collect taxes, so the living standards of the farmers on Kinmen Island were pretty good.

However, the price of sweet potatoes is not high. Sweet potatoes are sold to Zheng Zhilong for only three cents of silver, which is far lower than the purchase price of rice.

Li Guodong didn't know that when he went south to Fujian, the price of grain in Jiangnan had risen to nearly two taels of silver per stone! The price of grain in the north even broke through the mark of three taels of silver per stone!

The old farmer took out a few sweet potatoes from the cellar. Li Guodong took a look and saw that the sweet potatoes were only the size of duck eggs. He was a little disappointed: "The sweet potatoes are still small. When you choose seeds in the future, you should pick out all the big ones for planting."

"We have also selected large ones to make seeds. We have been raising them for several generations, and when they were just planted, they were even smaller."

Afterwards, the old farmer and his wife roasted a few more sweet potatoes and let Li Guodong taste them.

After a while, the old farmer dug out the sweet potatoes buried in the fire, tore open the skin, and a strong fragrance wafted out. Li Guodong couldn't wait to hold the sweet potatoes, blew the breath, and finished it in just a few seconds.

"It's so fragrant!" Li Guodong sighed, "Uncle, please buy you some sweet potatoes before I go back."

"No problem, but you can plant it?"

"I'm not very good at it, so I have to buy more and go back and think about it."

While talking, someone came over and shouted: "Mr. Li, the iron smelting furnace has been set up, Mr. Li is coming."

Li Guodong said goodbye to the old farmer and rushed back to the Zheng blacksmith shop with the craftsman.

Back to the blast furnace room, the blast furnace has been built, completely according to Li Guodong's design, with a heat storage room, ventilation pipes, and air supply outlets. The blower is being manufactured. The shell of the blower is made of wooden boards. A wooden pedal is installed. As long as the pedal is pressed, the wooden disc will rotate. The iron shaft and iron gears drive the wooden fan to rotate, and fresh air is supplied to the blast furnace.

The shaft, gear and transmission shaft are made of iron, and are made of fine iron made by blacksmiths one by one. Because wooden gears are easy to be damaged, the gears will be damaged after being used a few times. Similarly, wooden bearings are also easy to wear. Therefore, the water mills that appeared in the Han Dynasty and the vehicles and ships that appeared in the Song Dynasty will have lower and lower work efficiency after a long time of use.

Although the iron gears made by Li Guodong are not involute gears, but ordinary iron gears back then, because the Zheng blacksmiths' craftsmanship is indeed exquisite, the gears created are shiny, and they have obviously made them into steel.

"It's actually a steel wheel!" Li Guodong exclaimed as he touched the gear, "The steel is better and less likely to wear."

Then the craftsmen assembled the gears, shafts, transmission shafts, discs, fans, rockers and other parts, and finally nailed the wooden boards and placed a seat above the pedal. In this way, the foot blower was done.

The carpenters were still building a wooden air supply duct. Someone here couldn't wait to sit on the seat and stepped on the pedal curiously. After just a few gentle steps, they saw the fan rotate at high speed. Of course, there is another disadvantage, that is, if a person's feet do not step on, they need to leave the pedal, otherwise the feet will not move, which will restrict the gear rotation and cause the fan to stop running.

Seeing this characteristic, Li Guodong understood that this was because he did not create a ratchet, so he could only step on it, and the person's feet left the pedal and let the pedal turn itself under the action of inertia. There is also a disadvantage, because the rotation of the fan also drives the gears, driving the pedal to rotate, wasting a lot of energy.

"If ratchets can be made, then you can build a bicycle." Li Guodong said to himself.

However, no craftsman heard his words, and everyone was shocked by the high-speed rotating fan. Unexpectedly, the speed of stepping on the pedal was not fast, and the speed of the fan was actually so fast!

When the wooden ventilation duct was completed, the craftsmen installed the ventilation duct on the blower. Someone stepped on the pedal, and several others felt it at the outlet and found that the wind was strong. Then the craftsmen connected the wooden pipe to the air supply outlet of the blast furnace.

The head of the blacksmith shop is Lin Shuijie. He is very confident in Li Guodong, a distinguished guest invited by Zheng Zhilong. He had heard of Li Guodong casting cannons in Tongzhou before. Seeing that everything was done, Lin Shuijie shouted: "Brothers, we are ready to start construction!"

According to Li Guodong's requirements, the amount of charcoal sent was reduced by 30% compared with the past.

——
Chapter completed!