Four days later, the caravan ships raised their sails and sailed away from the dock. Pen & Fun & Pavilion www.biquge.info

Together with 100 soldiers of the First Army, Tasa set sail for the royal capital.

During these days, Roland and Margaery made an agreement that Tasa could withdraw any amount of gold dragons from her shop, which would be deducted from the sale price of the steam engine, and Roland would have to pay an additional one percent interest.

This time, the saltpeter and ingots brought by the other party were almost twice as many as the last time, but with the deposit for the transformation of the two river boats, Roland still received more than 2,200 gold dragons, which was almost an unimaginable amount in the Demon Moon - even if he sold a month's ore, it was only 300 gold dragons.

After the caravan left, Maisie also had time to leave the border town for a while.

According to the agreement made with Ash, she will travel to the fjord islands to bring news about the West.

Roland specially wrote a long letter to her, in addition to expressing an attitude of mutual assistance and cooperation, he also hoped that the Five Kings would send some auxiliary witches to assist him. In the letter, he did not claim to be his brother, but negotiated the matter as the lord of the border town and the ruler of the western border. Although the chances of the other party agreeing to him were slim, he still had to give it a try - it didn't take much effort to write a few more words anyway.

The farewell location was in the castle's backyard, and all the witches had arrived.

Nightingale gave her a small bag of dried fish, and Lightning gave her a packet of pepper.

The other witches reluctantly stepped forward to stroke her feathers and hugged her goodbye—like goodbye.

"Don't worry!" she said, raising her head, "I'll be back soon, Goo!"

"What if Tiri doesn't let you come back," Lightning said worriedly.

"Goo......" The pigeon craned its neck and thought for a while, shaking its tail feathers, "Then I'll fly back secretly!"

"Then we will tell," said the little girl, earnestly, "and if you come back, I will catch a bunch of birds myself and roast them for you." And the beehive we found last time, keep it until you come and take it out together. ”

"Goo!" she nodded repeatedly, "Say yes!"

What else can you say? Roland was full of emotion on the side, it had only been a month, and he had completely turned Maisie to his side. Well done, Lightning!

"Goodbye everybody, then!" Maisie spread her strong wings, ran on the ground for a while, and then slowly flew up, circled twice, and then gradually disappeared to the southeast.

"She'll make it there. Roland looked at this sluggish movement and couldn't help but sweat for her.

"No problem," Lightning said without hesitation, then tilted his head, "It should be...... Right?"

Seeing Maisie away, Roland quickly returned to his busy daily routine.

This time, he was to draw a complete set of blueprints for the two ships to be rebuilt that the caravan had left behind in the Moonmoon Bay - and they would be the world's first steam-powered paddle steamers.

Thanks to the single power source, it is possible to connect the steam engine shaft directly to the paddlewheel without the need for a gearbox. Control the intake volume with multiple intake pipes to control the speed of the ship. When you want to slow down or stop the boat, simply close the intake pipe and let the excess steam escape from the exhaust port. At this time, the fire is still burning, and it is easy to speed up again.

The principle was not difficult, and Roland quickly drew a rough model. If you want to get accurate production drawings, you have to go to the site to measure the specific dimensions.

At this moment, Anna walked into the office with a book in her arms.

"What's wrong?" he put down his quill pen and couldn't help but smile.

"I'm done reading this book," she said, putting it on her desk, which was the book "Foundations of Natural Science Theory."

Roland's smile suddenly froze on his face, this is too exaggerated, it has only been a few months to read all the high school level mathematics and physics knowledge? He didn't ask the other party if he understood it, because Anna's reading meant complete understanding, otherwise she would definitely read it again and again, or come to ask herself.

"Are you trying to use a steam engine instead of a sail to power a ship?" Anna's attention was quickly drawn to the sketch on the table, "but ......"

"But what?"

"These two wheels are similar to paddling, right? they generate thrust when they turn, but half of them are exposed, which is equivalent to wasting some of the power. Why don't you bury it all in the water?"

"......" Roland was stunned, not knowing what to say. It is impossible for a person to be born to know, that is, she has made the above judgment based on this momentary impression alone?, he suddenly became interested, "Then what do you say should be done?"

Anna thought for a moment, picked up her pen, and began to draw on the paper.

Roland propped his chin and admired her with great interest as she made the picture in earnest—the bangs that slipped from the hairpin swayed back and forth with her movements, the slender eyelashes bounced twice from time to time, and the fair cheeks revealed a natural rosy. Although only the side of the face can be seen from this angle, the light reflects the contour that stretches from the bridge of the nose to the chin and then to the neck, creating a perfect and gentle curve.

"Would you like a fillet?" said the nightingale leaned over and put her hand between them.

"Well," Anna nodded, taking on the snack she had handed her, "thank you." ”

Roland, whose vision was blocked, coughed twice, and had to move his gaze back to the paintings on the table.

At first, Anna tried to bury the paddlewheel completely in the water with it horizontally, but this made it difficult to see the position of the wheel when the boat was docked, and it was easy for it to crash into the dock or trestle.

She then arranged the paddlewheel to the stern of the ship, which was a common practice, but the transmission setup was much more complicated, as the bulky steam engine was not suitable for the end of the hull, so that the propeller shaft and gearbox would occupy a considerable part of the hull.

And when Roland saw the new drawings she had drawn, he couldn't help but marvel at the other party's keen thinking ability again.

The sketch that Anna was working on was infinitely close to the arrangement of a single-shaft propeller, with the steam engine set at the bottom of the hull, the propeller shaft protruding from below the waterline, and four square blades attached to the ends, which looked a bit like a windmill.

"I don't know if that's going to work," she hesitated, "and it stands to reason that just keeping the paddles at an inclination will create a horizontal component, but I've reduced the paddle wheel, and four paddles alone may not be able to propel the hull." ”

"Absolutely, with a little modification. Roland took Anna's quill and drew the original shape of the propeller, "This shape of the blade is more suitable for spinning in the water than the shape of a windmill." You're exactly right, but the contractual requirement is to convert a paddle steamer, so let's do it the first way - it's not about technology, it's a business strategy. He paused, "I'm going to measure the hull data now, do you want to come with me?"

Anna blinked her azure eyes, "Hmm!"

After mastering the theory, the best way to learn is to verify it in practice.

......

"Nightingale?"

When Anna followed the prince to the door, she saw that the nightingale was still looking at the drawings on the table, and she couldn't help but speak.

"Ah, you go first, I'll come right away. ”

After comparing the sketches in her hand repeatedly, she came to the conclusion that the wheels were placed in a different position? )