Lu Wanjie ran to the corner with a red face, looked back and saw that there was no one around, and then she breathed a sigh of relief.

Thinking of Li Chengqian's words just now, her face was red all the way to the base of her neck.

At this moment, her little heart was pounding.

Li Chengqian's mouth said that the marriage was not going well, so he came to me.

It's nothing more than saying, if someone else is using my name to trouble you, I'll help you explain.

But when it fell into Lu Wanjie's ears, it was like 'I will marry you when I grow up'.

……

watched Lu Wanjie run away.

Li Chengqian glanced at Cheng Huailiang, and then at Changsun Chong.

At this time, the faces of these two people were as suffocated as eggplant sauce, which was extremely ugly.

Li Chengqian said with a dark face: "If you two want to laugh, laugh!" ”

He said it all, who would dare to laugh?

The two of them struggled to hold back their laughter, not to mention how uncomfortable it was.

Li Chengqian rolled his eyes: "Don't say that I give you a chance to laugh every time, three-two-one, if anyone dares to laugh, they will break their legs directly." ”

This time, the two of them didn't dare to laugh at all.

After the wedding banquet, Li Chengqian returned to the hotel where he temporarily lived.

When entering the hotel, Li Chengqian suddenly remembered something.

"By the way, Brother Chong, I forgot to inquire these days, is the price of grain in the south much lower than in the north?"

"Yes."

"How much lower?"

The eldest grandson thought about it: "The price of grain in the north is now thirty yuan a bucket, while in the south it is more than half cheaper. ”

"How much?"

"The price of grain in the south is at most ten cents a bucket."

"So much?"

Li Chengqian was a little surprised.

It's not half the problem anymore, it's already a third.

The difference between grain prices between the north and the south by half may still be in Li Chengqian's imagination.

But the difference is two-thirds, which is too big.

"Of course."

Changsun Chong explained: "Although the land in the north is more fertile than in the south, the rice harvest in the south is twice a year, while in the north it is only once. ”

"Then what if you want to transfer grain from the south to the north?"

Li Chengqian rubbed his chin and asked.

"It's not realistic."

In today's era, after all, there are no highways, let alone cars and other fast transportation equipment, so we can only rely on people to push and rely on horses.

But the speed of cattle and horses is too slow, if you transport grain and grass from Suzhou to Chang'an, it will take at least two months.

During these two months, there will be spoilage and loss of food destroyed by rats.

Using ten catties of grain as an example, excluding deterioration and destruction by external forces such as rats, it is already very good to have six catties of grain left.

Changsun Chong was very rational and said directly: "It is not unheard of before that the south-to-north grain transfer was done before Emperor Yang. ”

"But the grain from the south is transported to the north, not counting the loss on the road, Luffy alone is very expensive."

"And what if it's by water?"

Li Chengqian now really wants to put the south-to-north grain transfer into practice, so he has been struggling with this issue.

But Changsun Chong shook his head.

"Your Highness, don't forget what happened to us when we came, we are royal ships and we will encounter water thieves, not to mention those merchant ships transporting grain."

"Once the waterway is opened, it will have to be cleaned up and checkpoints will be set up along the canal."

"And although the waterway is fast, it is only ten days and a half faster than the land route at most."

"If you just take these ten days and a half months as a measure, then the final outcome will only be to increase the cost of the national treasury."

Although the eldest grandson Chong said so, Li Chengqian still had no intention of giving up.

Li Chengqian continued to ask: "What if you can let a merchant ship travel 500 miles a day and 300 miles at night?" ”

"Impossible, absolutely impossible."

Changsun Chong shook his head and said: "The boat on the water, even if it catches up with the weather with good winds and good days, traveling 200 miles a day and 50 miles at night is the limit, and 800 miles is simply impossible." ”

"No!"

The corners of Li Chengqian's mouth were high, and he said: "There are definitely ships in this world that can reach 800 miles a day. ”

As a descendant of later generations, Li Chengqian has seen a ship that can travel thousands of miles a day.

Traveling 800 miles a day is not too easy.

And, he's working on propellers right now.

Manpower coupled with natural forces, even if it cannot be compared with the steam engine and diesel engine of later generations, but the kinetic energy is already very considerable.

"You don't need to think about it, you just need to tell me, once there is a ship that can travel 800 miles a day, will it not be so difficult to transfer grain from the south to the north?"

"This ......"

"It does."

"If there really is a ship that can travel 800 miles a day, it will not take more than a month to transport grain from the south to the north."

Changsun Chong shook his head helplessly and said, "But in this world, is there really such a ship?" ”

"Yes."

"Even if you don't have it now, you will definitely have it in the future."

Changsun Chong's words deepened Li Chengqian's idea of continuing to develop wind propellers.

It was also from this day that Li Chengqian began to devote himself to the development of wind propellers.

As someone from the modern era, he is well aware of the importance of waterways.

Even in the era in which he lived in later generations, water transportation was still the leading force in the transportation industry.

Therefore, water transportation is very necessary and must be paid attention to.

……

Li Chengqian and his entourage, after staying in Suzhou for half a month, officially set off to return to Chang'an.

When he came, he was delayed for a lot of time because he had to send Gao Shilian by land.

Nowadays, there is almost no need to take the land route, just take the waterway, enter the canal along the Yangtze River and then enter the Yellow River, and you can reach Chang'an directly.

This is also thanks to the 'faint emperor Yang Emperor' of the previous dynasty, if it were not for him, Li Chengqian would not know how many crimes he would have suffered.

That said, it was thousands of miles to sail.

While on the ship, Li Chengqian devoted himself to studying how to improve the ship, and also used his drawing talent to draw the map in his mind.

On top of this, he also drew the scenery and scenery of the places he passed along the way, and left annotations in it.

By the time we arrived at our destination, those atlases had become relatively complete geographical atlases.

……

On this day, Chang'an City thundered and thundered, and heavy rain poured.

A thin girl ran home in the heavy rain, put away all the clothes that were hanging outside, and hurriedly carried them into the house.

Finally, take a small wooden basin to catch the rainwater that is leaking from the broken part of the roof.

There are also poor people in the prosperous era, and Chang'an City at the foot of the Son of Heaven is the same, rich in the east and expensive in the west, poor in the south and cheap in the north.

And the poor people of this era are completely different from the later generations.

In the next life, no matter how poor you are, you will not starve to death, and you will always have a way to eat.

But in such an era, the poor think about how not to starve to death, how to eat a full meal.

It is never easy for children born into such families to live.

In the morning, she went two blocks away to help an elderly couple clean the yard and fill their water tanks with clean water.

The couple's son was a peddler who ran long distances outside, and he would come home once every three or five days, and each time he would settle three or five copper plates for her.

The girl has no concept of wealth and poverty, does not feel that it is good to be rich, and does not feel that poverty is a sin.

For her, the biggest surprise in the world is that her mother can bring back some leftover snacks for others to eat after she finishes helping the big family.

"Yikes!"

As if remembering something, she got up and ran to the broken cupboard, and after digging out a cloth bag from it, she ran into the rain.