Tang Ping led a few people to the river, and the waterwheel was almost ready.

The keel waterwheel is recorded in Song Yingxing's Tiangong Kaiwu, and there are several kinds of them.

Tang Ping chose the kind that was driven by wind and water power at the same time.

Although the water level of the river in Shanghe Village has dropped due to drought, the river is still relatively turbulent.

And the wind in the northwest has always been not small, and this is still an outlet.

So when the waterwheel was erected, Tang Ping felt that he could draw up the water in the river by relying on wind and water power.

As for the fields in the village, he dug a lot of ditches as early as last month when he asked everyone to dig pits and compost them.

As long as the water can be sent up and into those ditches, it will be easy to irrigate the land in Shanghe Village.

"This thing ......" Li Shimin is now blushing when he sees a good thing.

But there's no way, who calls his nephew a good thing here, and there's no other place to do it?

"Wang Tieniu!" Tang Ping shouted.

Wang Tieniu rubbed his hand on the clothes behind his waist, wiped the beads of sweat on his forehead, and then came up and respectfully shouted to Tang Ping: "Owner! ”

"Have you learned how to do this waterwheel?"

"If you go back to the proprietor, you have learned everything!"

In whose hands is such a thing not the kind that is passed on to children and not to women? As a result, when I got to the proprietor, I taught myself casually.

"Then give that mold to this General Li!"

"Yes!" Although Wang Tieniu was a little reluctant, he still came over with a box and handed it to Li Shimin.

This is the model that Tang Ping bought, a set of miniature keel waterwheels.

Li Shimin and Li Jiancheng glanced at each other, the helpless affairs of the Manchu Dynasty's civil and military affairs, when they arrived at Tang Ping, it was just a casual remark!

The key is that how to reward Tang Ping has become a big problem now, and it is not too easy for him to become an official and a knight for these achievements.

But a few people still hope that he can keep a low profile, and now a few people come all the way to avoid the eyes and ears of others and come quietly.

Therefore, he knows that these merits are his, but he cannot announce them to the world for the time being.

Thinking about it, it seems that I can only give some money.

Although they didn't know why Tang Ping needed gold, what they gave was completely disproportionate to what Tang Ping paid in their own eyes.

"Little Brother Tang......"

Before Li Shimin could say anything, Tang Ping said again: "Now is not the time, you come in a month, I will give you some ......"

Tang Ping wanted to talk about seeds, but it was inappropriate to think about it, so he could only explain: "It's the kind of thing called potatoes in the spicy soup this morning." I have a way to get you to plant on a large scale."

The northwest is a one-season potato growing area, which is sown at the end of April and early May every year, and harvested in autumn.

If it is Hunan and Hubei, it is a two-season cropping area in central and southern China, and it can be planted and harvested twice a year.

This is the most productive crop that Tang Ping can think of growing here.

You must know that the excellent spring wheat seeds he brought back can reach a maximum yield of 500 catties per mu here.

And the yield of potatoes can reach several times that of wheat.

"Well, that stuff is delicious!" Li Yuanji shook his mouth, he was thinking about that thing just now after eating, but he didn't have time to find a chance to ask.

"How's the yield?" Li Shimin is most concerned about this, things are delicious, but if the yield is too low and only planted for deliciousness, it will definitely not work.

"I remember that the average yield per mu should be 3,000 to 5,000 catties. However, if you want to get a discount on your side, it is estimated that it will only be half. ”

After all, one acre of land in the Tang Dynasty is about eight-tenths of an acre of land in modern times, and if you plant here, both fertilizer and pest control are not as good as modern society.

Therefore, Tang Ping's conservative estimate is that it would be good to have half.

As soon as Tang Ping's words fell, Li Shimin was shocked, and almost even the waterwheel just now fell to the ground.

3,000 catties to 5,000 catties, and more than 1,000 catties when you fold it in half, can this world really have crops that yield thousands of catties per mu?

You must know that in the old and new Tang books, or in the Turpan documents, the average level reflected in the Tang system is one to two stones per mu, and the southern rice can reach three stones, that is, 276 catties per mu of the city.

However, this does not mean that the average yield of millet per mu in the northern dryland has reached such a high level, in fact, the millet harvest in the vast majority of dryland is still about 100 catties.

So the yield per mu of 1,000 catties, if Tang Ping hadn't said this, Li Shimin would have already shouted "come here".

"Don ...... Little Brother Tang, what you said is true? Even so, Li Shimin asked again to confirm.

"It should be about the same, this time I will plant 50 acres in Shanghe Village first, and the potatoes are not planted with seeds, but cut into blocks according to the sprouts and sown on the ridges!"

The so-called ridge is composed of high convex ridges and low concave ridges, this planting method was very popular in the north of the Han Dynasty, so Tang Ping did not need to teach them anymore.

"The buds that I will cultivate here at that time will be planted in Shanghe Village for fifty acres, and you can take more than that, and ask the department in charge of agriculture in the imperial court to try to plant a season first."

Seeing is believing, after all, no one in this era can really imagine that crops can have such a high yield.

Therefore, it is impossible to spread it to the whole country without trying it.

On the way back, Li Shimin was still dizzy, with a yield of 1,000 catties per mu!

That's a thousand pounds!

Even if Tang Ping said that it is not delicious to eat for a long time when it is used to make food, you must know that many times due to wars and natural disasters, many people may not be able to eat enough. It doesn't matter what tastes good or not? In the real famine years, even the bark and grass roots have to be robbed.

Why does Tang Ping have such a ability in farming, is he a teacher of the god of agriculture in heaven?

However, Li Shimin is most worried about Tang Ping's safety, last time someone came to report that some people from the Wang family were staring at Shanghe Village, but because the other party did not move, Li Shimin did not move those people, otherwise it would be clear that Tang Ping had something to do with him.

Now it seems that even Lao Cui and Lao Du, the two veterans and Lu Yi are not safe.

"Big brother, take out the sword order!" Li Shimin suddenly said to Li Jiancheng seriously.

"Well, looking at the current situation, no matter how much we hide it, we can't cover his light, so we use the sword order to ask the Pei family to send someone to Shanghe Village."

The so-called sword order was a great favor to the Pei family when Li Tang founded the country, and the Pei family sent three sword orders to the Li family.

And the Pei family is the existence of the pinnacle of Datang's personal force.

After so many years of using two, there is still the last one left.

"The third brother will go to the Pei family, and use the sword order to invite the contemporary sword saint of the Pei family to come to Shanghe Village to protect Tang Ping."

"Okay! I'll get back and give me the binoculars! ”

"Ahem...... That big brother, you will keep an eye on the Ministry of Industry when the time comes, and let their craftsmen learn how to make the new keel waterwheel as soon as possible. ”

"Second brother, my telescope!"

"......" Li Shimin was helpless, if the telescope was used well on the battlefield, it might even determine the outcome of a battle.

But robbing my brother's things like this doesn't seem to be very authentic.