It's true that manpower is not valuable, but there is a threshold for everything.

A mine is so big, the artificial mining efficiency is limited after all, no matter how many people there are, it is impossible to start work at the same time, and they can't even find a place to put their feet.

Blast furnace iron smelting has greatly improved the efficiency of iron smelting in Datang, and even through this method, the capable craftsmen sent by Changsun Wuji have already touched the key points of steel smelting, and they only need to experiment more, and they will soon be able to get the hang of it.

The problem of smelting efficiency, which originally plagued the Tang Dynasty, was replaced by mining efficiency, which has become the most headache for the imperial court at present.

There was a war on the front line, hundreds of thousands of strong men were drafted and sent to the north, and the young people who stayed behind were also responsible for farming, and they could only help in their spare time.

But iron ore is not available everywhere, and some counties do not produce iron at all, and Changsun Wuji has been trying to find a way to solve this problem.

The previous matter of Li Yuanjing's capture was also supported and rejected by the eldest grandson Wuji, and if he really used those prisoners, he would also give priority to using them for iron ore.

In the imperial study, the eldest grandson Wuji's mood is very entangled now.

The matter has been truthfully reported to Li Shimin, and it is naturally up to Li Shimin to decide how to make the decision next.

On the contrary, Cheng Zhijie and Li Yuanjing had their own ghosts, one simply put on a posture to watch the excitement, and the other snorted at the other.

"Can't be replaced by something else?" Li Shimin's face was also full of depth.

One can top the work efficiency of two or three hundred people, if it weren't for the eldest grandson Wuji and Cheng Zhijie opening their mouths at the same time, Li Shimin would not want to believe a word.

Although he believed it, the problem still existed, a guy would have to use up about 3,500 catties of iron, and a blast furnace could not smelt 3,500 catties of iron in a day.

"Not only can't, but some parts must also be made of steel, such as buckets, gears, bearings, wheels, etc., otherwise they can't adapt to all kinds of high-intensity work in the mine." Li Yuanjing shook his head directly.

As for how to make steel, Li Yuanjing knew that in addition to adding some scrap steel to the molten iron, he also needed to add limestone, and the rest was not clear, but Li Yuanjing did not plan to work it.

If you don't even give a compilation, how can you have a good thing to let people work every day without giving you food and drink?

"But it can be reduced, the iron ore should not be so large, if it is improved, it will be almost the same for a thousand catties, but it needs manpower to cooperate......" Li Yuanjing said his own idea.

Iron ore excavators are of little use, and with manual excavators, the strength is always a short board, and it may not be easy to use directly from the past.

"Small, big?" The eldest grandson Wuji was stunned, and instantly understood what Li Yuanjing meant.

"What do you mean?" Li Shimin was a little puzzled.

"Your Majesty, iron ore is not a small piece like you see, but a whole piece, which needs to be carved into small pieces by manpower to transport it, if you guess correctly, Your Highness should want to use the small one to dig and the big one to crush?" The eldest grandson Wuji wanted Li Shimin to explain, and looked at Li Yuanjing.

"Yes, you only need to manually dig a few small holes in it, and after mining, you can grind it directly on the spot, and you can even build a conveyor belt that can be dragged by oxen to transport the ore directly to the iron-smelting workshop." Li Yuanjing nodded, and then said:

"These things seem to cost materials, but they can be done in the shortest time, with the least number of people, the most work, a day or two may not be obvious, but what about five years and ten years? If these things are used, the amount of mining in a year will be more than ten times higher than before, and one year is equivalent to ten years of mining!

And the royal brother ignored a problem, isn't the scarcity of steel precisely because the output is too small? Once these things are used for mining, the production of steel will inevitably increase exponentially, and what is the amount of steel used now compared to the increased amount?

In addition, the younger brother also hopes that the royal brother can grant the younger brother an iron mine, the younger brother himself is responsible for mining, he is responsible for smelting, these steel will be used for various research, now the excavator is reduced to make samples, you need to smelt the existing excavator to do it! Li Yuanjing cried at the right time.

"Your Highness, you're enough......" Eldest Sun Wuji grinned, if Li Shimin hadn't been here, he would have used his hands and feet a long time ago.

"Brother Eldest Sun, what kind of eyes are you?" Li Yuanjing looked at the eldest grandson Wuji with some puzzlement, and didn't understand where this product came from with such a big grievance.

"That's it! If I give you materials, how much are you going to earn? Li Shimin interrupted the nonsensical quarrel between the two.

If Li Shimin knew that the anger of the eldest grandson Wuji came from Li Yuanjing, and asked the eldest grandson to bring him a message and ask him to prepare hundreds of thousands of catties of iron, it is estimated that Li Shimin would not be so calm.

"Five hundred! I have to do secondary processing, I have to buy all kinds of materials, and I have to give people a high salary, and I can't earn much if I give 500 yuan, and I don't have to pay 100 yuan! Li Yuanjing thought about it seriously, and said with an expression of wanting to cut meat.

"Then when will these 20,000 yuan be returned?" Cheng Zhijie was very dissatisfied and complained.

One is less than a hundred yuan, two people are divided into fifty yuan, and he has to sell two hundred units to barely recoup.

But in the current situation, in addition to the fact that the imperial court can buy it, this kind of thing is not allowed to be sold to the outside world, and how much can the imperial court buy?

"Brother Cheng, this is your mistake, is the imperial court buying these things to make money? Of course not, since the imperial court is not to make money, why should we still make money? You can't be too short-sighted in life and work, you and I are both Tang humerus, and we should focus on the overall situation! Li Yuanjing scolded Cheng Zhijie in a stern tone, then turned his head to look at Li Shimin, and said in a tone of self-sacrifice:

"Brother Huang, for every small one in the imperial court, give 500 guan, and don't want 1,500 guan for the big one, just 1,000 guan!"

Cheng Zhijie pursed his mouth, and said like an angry little daughter-in-law: "It's better to let the court do it yourself, and do it yourself at a loss, why?" ”

According to Li Yuanjing's statement, a small one is about 1,000 catties, and 500 guan can only earn about 100 guan, and the big one is about 3,500 catties, why can't it be 1,500 guan? Now it's only a thousand, such a fold, and the small profit is gone, is this still a bird?

"Money! Money! Money! How do you know about money? The big one thousand is basically the cost, such a good thing, can the imperial court only need a hundred units for you and me to lose money? Why can't there be 511 units? Can't you make tens of thousands? Besides, you think this thing will last a lifetime once it's made? People still have a headache and brain fever from time to time, and things are broken and need to be repaired, can the court not give money? Can you repair without making money? Li Yuanjing suddenly felt that Cheng Zhijie was so ignorant, didn't he know that most of the mechanical things were after sales?

Especially now that the only family, even if it doesn't make any money, as long as Li Shimin agrees, it will definitely make a lot of money in the future, and it's not really that it doesn't make money.

"Okay, auxiliary, you calculate how much you need, and buy some if it's suitable!" Li Shimin made the final decision, and then looked at Li Yuanjing: "You don't have to think about iron ore, if you have any new ideas to use iron, come to me, and I will approve it for you!" ”