If you ask the Tang Dynasty to be the first in cavalry, Li Jing is worthy of his name.

If you ask the Tang Dynasty land battle first, Li Tao deserves it.

But if you want to ask who is the first person in the Datang Water War, I'm afraid no one can answer.

If you ask who knows most about ships today, the only one is Li Xiaogong.

The history books left him with the words 'the famous king of the clan, known as the military meritorious', which is not a joke.

In fact, this is also what Li Chengqian only learned after he crossed into this world.

Since Li Yuan Jinyang raised troops, Li Xiaogong was in charge of passing through Bashu, and later served as the governor of Kuizhou.

Later, he built a ship for Datang to practice the navy, and cooperated with Li Jing to destroy Xiao Milling and pacify the south of the Yangtze River, which can be described as brilliant achievements.

It's just that he remained neutral during the Xuanwumen Change, so he never won Li Shimin's trust.

Li Shimin only let him be the secretary of the Ministry of Rites, and by the way, he was crowned the king of Hejian County.

Not to mention, this person is definitely a talent among talents.

In his previous life, Li Shimin did not reuse him, which is a pity.

It's just that because of Li Chengqian's appearance, this life is different.

Not to mention the relationship between Li Chongyi and Li Chengqian.

Just said that he alone in the entire Tang Dynasty knew the most about shipbuilding and water warfare, and Li Chengqian couldn't let him continue to be so depressed.

……

The day after Li Shimin left the palace, Li Chengqian came to Li Xiaogong's house.

Far away, you can hear the singing and dancing in the house, a lively scene.

This old prince, who had brilliant achievements in his early years, is certainly not a fool.

The so-called person who has high merit will definitely die, and he also understands it, so he retreats bravely at the peak.

entertains himself with singing and dancing beauties and fine wine all day long, and others say that he is willing to fall.

But the wise know that he is doing this to prevent the king's suspicion of self-staining.

Only when you have a small reputation and a bad reputation can you keep the king from suspicion and let yourself and your descendants live a long time.

Seeing Li Chengqian coming in, the old prince was stunned for a moment, and then said, "Why are you running to my house like this little hairy child?" ”

"Of course, there is something serious to discuss with the clan uncle."

Li Chengqian smiled and walked in front of Li Xiaogong.

"Serious business?"

"What can you do?"

Li Xiaogong looked up and laughed: "Don't frame me, are you worried about the wine in my house again?" ”

Last time, Li Chongyi's kid stole his wine and ran to Li Chengqian's house, of course he knew.

Otherwise, Li Chongyi could not have been thrown by Li Shimin into the mud pit where he had been rolling with Cheng Yanjin in the western suburbs for more than half a year.

Li Chengqian was also embarrassed, and said with a dry smile: "How is it possible, how can I worry about the uncle's wine, I really have something to tell the uncle." ”

After the words fell, Li Chengqian took out the drawings of the ship he designed from his cuffs and showed them to Li Xiaogong.

"I know that our Datang has the most research on shipbuilding is the clan uncle, so I specially brought it to the clan uncle today."

Li Xiaogong took the drawings handed over by Li Chengqian in disbelief.

After reading it, Li Xiaogong raised his eyebrows, pointed to the stern of the boat and asked, "What is at the bottom of the stern?" ”

"It's a propeller."

"Propellers?"

"Yes."

"The propeller, pushed by manpower or wind power, uses a bearing to drive the gear below, and the gear then drives the conveyor chain, and the conveyor chain drives the underwater propeller."

"The propeller rotates underwater to generate power to propel the boat forward......"

Li Chengqian hurriedly pointed to the propeller and said, "Uncle Clan, this propeller push is definitely a good idea, I know." ”

"But if you want the propeller to have a lot of propulsion in the water, you have to have a very fast rotation."

"If you can't get the speed, you have to increase the propeller and change it to a worm shape."

"But after changing to a worm shape, the material became a problem again."

"I really can't help it, uncle, now I can only rely on you to help me."

At first, Li Xiaogong only thought that Li Chengqian was joking, but it can be seen that Li Chengqian explained seriously, and he also listened carefully.

But the more he listened, the more frightened he became.

I was surprised that Li Chengqian was so old that he could research this kind of thing.

The second surprise was that Li Xiaogong was very interested in ships, and as soon as Li Chengqian opened his mouth, he could imagine such a scene.

Li Xiaogong looked at Li Chengqian with surprise on his face: "Is this really made by you?" ”

"Or else?"

"I also made a bet with my father."

Li Chengqian sighed: "If I lose, I'm afraid I will be beaten by my father for dozens of rulers." ”

Hearing this, Li Xiaogong was happy.

"I am not afraid, because a ship that travels 500 miles a day can definitely be built."

"It's just that something needs to be improved."

"Improvements?"

"That's right!"

The eyes of the old and the young met.

The next moment, Li Chengqian smiled: "So, is the clan uncle willing to help me?" ”

"Hey, what to help or not, it's all good for Datang, how can I not care?"

Later, the old and the young began to discuss how to improve the drawings drawn by Li Chengqian.

After all, Li Chengqian came from a later life, and his ideas were very novel, but there were some things that were not quite in line with the current situation.

Hearing Li Xiaogong's words, Li Chengqian was relieved.

Someone finally helped me.

Li Xiaogong nodded Li Chengqian's head.

"You're hitting a dead end now."

"Did anyone tell you that a ship can only have one propulsion power?"

Li Xiaogong pointed to the propeller and said: "If you can't reach the speed you want, you can install a few more." ”

"If one is not enough, two will come, and if two is not enough, four will come, and I don't believe that it is not enough."

Hearing this, Li Chengqian suddenly had the feeling of seeing the bright moon through the clouds and mist.

It seems that his own ideas are too naïve, and he only thinks of using a propeller to propel the whole ship.

Before Li Chengqian could speak, he heard Li Xiaogong continue: "At the same time, I also want to point out a problem to you. ”

"You can replace a normal oar with a propeller, that's fine, but you don't need anything to replace the sail."

"In particular, it's impractical to drive the propellers with wind power."

In fact, Li Chengqian also discovered this point.

The model boat he made was okay to drive the wind, but it was a bit too much to drive the big boat.

A ship full of grain must weigh at least about five or six tons, and how big a fan can it move.

Li Chengqian scratched his head and smiled.

"Uncle Clan, if you have nothing to do lately, how about you accompany your nephew to build a ship?"

"Okay."

Li Xiaogong smiled and said, "If you don't understand anything, just come to me and let me build it for you myself." ”

Hearing that Li Xiaogong agreed, Li Chengqian was overjoyed.

Preparations for shipbuilding began immediately.

He first asked the carpenters in the house to buy iron pear wood specially used for shipbuilding, and polished it finely, and then made some prototypes of propellers.

then took these prototypes and found Li Shimin.

At this moment, Li Shimin is reviewing the folds in the palace.

Li Chengqian swished and pasted it: "Ah, my beloved old father, is he busy?" ”

Li Shimin glanced at him with caring eyes, and then lowered his head to look at the twists and turns.

Li Chengqian bared his teeth and smiled: "Father, discuss and discuss, borrow some money?" ”