A wooden shelf was erected, the bamboo was carefully selected first, and then the placement was adjusted to determine that it was suitable for assembling into a whole boat, and then the interception began.

Each piece of bamboo is cut into 21 meters long.

Only then do you start shaving the outer skin.

A total of 18 ingredients were selected for peeling.

There is only one planing knife, so this work is mainly done by Yu Le.

Li Zhi, on the other hand, under the guidance of Yu Le, used the pine resin oil that was cut back in the center of the island before, put bamboo slices on the paste, and then lit a fire to smoke the bamboo that had been peeled off.

It's quite a long process to make, so it's done every day.

Two men, basically have no free time.

At this point, it's time to start thinking about redesigning the sails.

The previous sail, due to the first design, was not very experienced, and the Bernoulli principle was not used very well. Therefore, when sailing at sea, the main power is by dynamic pressure, that is, pushed by the wind.

But now in the inland river against the trend, if you still rely on the wind to push and run, without the help of static pressure, it is estimated that you will not be able to walk.

So, it needs to be redesigned.

And when discussing this issue, it is natural to invite Lu Lin in.

Without her as a theoretical designer, it wouldn't work!

Yu Le, Lu Lin, and Li Zhi also gathered together as staff officers.

The three of them scribbled and discussed the shape of the ship for three days.

In the end, Lu Lin held a big belly and said: "Don't go up the mast at all, just make it into a fixed-wing one! In this way, the southeast and northwest winds, except for the first wind, can go in any other wind direction, that is, you have to take a zigzag route." But it doesn't matter, the Yangtze River, which is several kilometers wide, also allows us to take a zigzag route. ”

The two men asked her together: "What kind of fixed wing?"

Lu Lin said: "It's a fixed wing like an airplane wing, which doesn't need to be inserted into a mast." Of course, our shape doesn't need to be made into an airplane wing. ”

Yu Le said: "What kind of shape is that? Can you still use a mast? We are using it now, so we must also use a movable mast." ”

Lu Lin pondered for a while before coming up with an analogy: "Have you eaten all the moon cakes?" Take half of it, and that's the shape of our fixed wing. ”

"You see, this half of the moon cake is flat on one side of the incision, but on the outer edge, it is curved. In this way, let's install this fixed wing like a moon cake on the deck, no matter which direction the wind blows in, we only need to adjust the angle of the fixed wing according to the wind direction, using Bernoulli's principle, the arc side, the air flow rate is large, the natural pressure is small, the pressure on one side is large, the pressure on the other side is small, and then the ship will be pressed away. ”

"As for the specific size, it depends on the situation. The five-meter width has been fixed, so this fixed wing can only be made to be four meters wide at most, and there must be an aisle. If it's tall, I recommend making it two meters tall. Then add a fixed frame at the bottom, the fixed wing is movable, can be steered, and can be disassembled. When sailing, watch the direction of the wind and adjust the direction of the fixed wing at any time, and when the boat is stopped, you can lift the sail down. ”

Yu Le took a branch on the ground, drew it for a long time, figured out the shape of the fixed wing in his cousin's mouth, and then asked a question: "That...... Is your fixed-wing really practical? Is the thrust generated big enough to propel our 10-ton ship?"

Lu Lin said with certainty: "Yes! Definitely can! Don't you want to think about it, a hundred-ton plane, it can be lifted to the sky." If you are a big ship weighing more than 10 tons, if you go against the current, how much force do you think it will take to push it? Surely you don't need more than 10 tons of force, right?"

Li Zhi shook his head: "That's not necessary, the ship is moving forward, as long as it overcomes the resistance with the water, it is very simple." There is no need to compare it with the weight of more than a dozen tons. ”

Yu Le said: "That's right, not to mention a dozen tons, a big ship of hundreds of tons, if you want to put it on the surface of the water and stand still, I can pull it up alone." Our kind of bamboo boat, the draft is shallow, the resistance is small, and if you need to overcome the opposite direction of the force given by the countercurrent, I estimate that there are a few hundred catties to be able to start the boat. Anyway, if you let me pull the rope upstream alone, I will definitely be able to pull it. ”

Lu Lin said: "That's not simple, the head, middle and tail three fixed wings, equivalent to three sails output, if the wind speed is normal, at least it can provide thousands of catties of power." However, because it is against the current, this boat will definitely not be able to go fast, I estimate that it is four or five kilometers per hour, of course, it may not be, at most it can reach a speed of three or four kilometers per hour. It's like walking at the same speed as a person walking. ”

Li Zhidao: "It's enough to have a walking speed. Anyway, we have a lot of time. The speed of three or four kilometers per hour, anyway, living on a boat, every day at dawn the boat will leave, and then stop when it is almost dark, ten hours a day, that is, thirty or forty kilometers. It's only a little more than 1,000 kilometers since we went to Central China, so wouldn't it take us a month to get there?"

Yu Le smiled and said, "Brother Li, this can't be counted like this." If we look at the direction of the wind and take a zigzag route in the Yangtze River, our distance will at least be doubled!"

"And it depends on the road, when there's no wind, we have to stop, when it's raining, we have to stop, when there's a flood, we have to stop. If we can walk an average of 10 kilometers a day, that's not bad. ”

Li Zhidao: "That's enough." It's only a three- or four-month trip. We will leave after spring next year, taking advantage of the southeast wind, until the end of summer, which is enough for us to go to Hanyang. ”

A total meal, so the question of the sail, so determined.

According to the idea of cousin Lu Lin.

Build a fixed wing!

However, one takes into account the specific production materials.

Yu Le found that this kind of fixed wing uses a lot of canvas.

The original two large canvases, that were definitely not enough.

Therefore, Yu Le put his mind on Shen Juan.

He asked Shen Juan to help weave cloth!

At this time, Shen Juan had a few women to help, and the boat of cotton that she originally brought back had been used up.

Of course, the results are quite fruitful!

Fifteen quilts are large and consume the most materials.

One pillow per person.

The clothes are two new sets per person, plus the two sets of security uniforms originally worn, and if they are repaired, they can also continue to be worn, that is, there are three or four sets of replacements.

Men's underwear, women's corsets and trousers, and socks were all cut out.

What is particularly admirable is that she also sewed several sets of baby clothes for Wu Yun's daughter Xiao Liu Xi and the unborn child in Lu Lin's womb.

Small and large ones, several sets, from birth to between two years old, have to be worn.

(End of chapter)