When Zhang Yunwen came out of the prison, a cool breeze blew, and he couldn't help but tighten the clothes on his body.

When I looked up, I saw that the branches on both sides of the road were already bare, and the occasional few dead leaves that stuck to the branches were shaking in the wind, as if they would fall to the ground in the next moment.

Before you know it, the seven years of martial arts are about to pass.

In the past few months, Zhang Yunwen has been immersed in the general prison almost every day, and even the early dynasty rarely participates in it, except for the necessary meetings in the imperial court. Originally, Li Shimin had a big opinion about him, but when Zhang Yunwen took out nearly a hundred grenades a month later, he stopped talking and didn't care whether Zhang Yunwen came to the early court or not.

In addition to the hundreds of grenades made in the first month, Zhang Yunwen was finally able to use the blast furnace to smelt red molten iron. Looking at the molten iron emitting white smoke and steaming heat, Master Lu and the other craftsmen were suddenly overjoyed, and they actually hugged each other. And Zhang Yunwen also distributed 100 copper coins to those hard-working craftsmen on the spot.

The steel is smelted, and the rest is much easier. On the spot, several sword casters poured the molten iron into the mold to create a horizontal knife. After the horizontal knife is formed and processed, try it with the knife stone, and suddenly, the wide knife stone is splashed with sparks, and the horizontal knife is cut out of a deep mark, but the blade of the horizontal knife is not bent in the slightest.

The quality of this horizontal knife is much better than usual!

Then, Zhang Yunwen began to use these steel to build each component of the crossbow, and then put it together and tried it, but the steel bow and crossbow were less effective than the wooden crossbow. Zhang Yunwen couldn't help but ponder, what caused such a result.

Finally, when he saw the coiling dragon spiraling up from the pillar, he suddenly remembered something.

Spring!

In the past, molten iron smelted was not suitable for making springs, but molten iron smelted by coke was different. The springs made from it have excellent elasticity.

Zhang Yunwen designed the spring on the bow and crossbow, and fixed two pulleys at both ends, so that the friction when pulling the string is much less and it is easy to pull apart.

Try it with the new bow and crossbow, the range reaches one hundred and twenty paces, and the moment the arrow is fired, the crossbow machine has less tremor and is easy to aim.

At this time, Zhang Yunwen was a little satisfied, and immediately ordered to use this bow and crossbow as a model, and then make two hundred pairs.

However, as soon as this order was given, the middle craftsman suddenly had a bitter face. Master Lu even asked, "My lord, do you think we won't do anything else in the next few months, just making this crossbow machine?" ”

Zhang Yunwen was suddenly puzzled: "What, is it very difficult to make two bows and crossbows?" ”

Master Lu stretched out three fingers and said, "Three days!" Even a full-time bow and crossbow craftsman can assemble and calibrate a crossbow machine from the final product to the final product, and it will take three days to make a crossbow machine! ”

Zhang Yunwen suddenly asked a little strangely: "Don't you know that each person only operates one step, and after doing it, it will be passed on to the next person!" ”

Master Lu was stunned for a moment, thoughtful.

Seeing this, Zhang Yunwen further explained: "This method of one person only doing one step is called an assembly line. For example, to make a crossbow machine, which is divided into eighteen processes, after you complete the first step, immediately hand it over to the next person to do the second step and you do the first step. When the second person completes the second step and hands the crossbow to the third person, you just finish it and hand him over to do the second step. Then you start doing the first step again. And so it goes......"

Before Zhang Yunwen's words fell, Master Lu said excitedly: "You can make a lot of crossbow machines, and the time required is very short!" ”

Nodding, Zhang Yunwen added: "And only one step is completed, no superb skills are required, only a little training is needed to work, so that many apprentices can directly participate in the operation of the assembly line!" ”

"The general is really a god!" Master Lu praised it.

However, when hearing this sentence, Zhang Yunwen always remembered the sentence that Liu Bei often said to Zhuge Liang in "Romance of the Three Kingdoms": "Mr. is really a god!" ”

Although Zhang Yunwen is right, there is a problem in the actual operation, that is, due to the different sizes between the various parts, it is extremely difficult to assemble, either too big to install, or too small to be loose after being installed.

Zhang Yunwen then remembered that these craftsmen now build things based on experience, and they are estimated to be as long as they are, and as wide as they are estimated. Very inaccurate. Therefore, he said that it is necessary to unify weights and measures, and the production of these parts must not be estimated, but can only be measured with standard tools.

However, this unified weights and measures was a major event and had to be reported to the imperial court, so Zhang Yunwen had to put it aside for the time being.

After discussing the feasibility of the assembly line with Lu Dajiang and others, Zhang Yunwen was sent out as a supervisor and slowly walked home. He hadn't been home for three days, and he had been living in prison.

Although he has lived a life of almost isolation these days, however, he is well aware of the major affairs of the DPRK and China.

First of all, Li Shimin's edict ordered Si Sha to eliminate the world's monks, nuns, Taoist priests, and female crowns, and his diligent practitioners moved to the big temple and gave them food and clothing, and there was no lack of orders. Those who are obscene and vulgar will be ordered to stop and return to the village. There are three temples in Beijing, two temples in view, one in each state, and the rest are all gone.

Of course, Yuan Tiangang's Baiyun Temple is one of the two views of Beijing.

Then, the edict posthumously sealed the late prince as the king of Xi, and said that he was hidden; King Yuanji of Qi was the king of Ra and was buried with a ceremony.

Soon after, his eldest son Li Chengqian was appointed as the crown prince.

When these major events happen, Zhang Yunwen will always come to the court meeting appropriately and watch everything that happens in a lively mood.

In this way, time passed imperceptibly.

Zhang Yunwen, the last court meeting of Layue, also participated. At the court meeting, Li Shimin announced that the new year will be changed to Zhenguan, and next year will be the first year of Zhenguan.

There is a saying in "I Ching: Under the Department of Resignation": "Those who are rigid and soft are also those who establish their foundations." Flexible, fun-timers. The one who is good and the bad is the one who wins. The way of heaven and earth, the chastity of the viewer also. ”

At the court meeting, Zhang Yunwen proposed to re-plan the standard weights and measures, and after speaking, he also said: "The reason why Qin Shi Huang ruled the world back then was related to his unification of weights and measures in Qin. At the beginning, all the crossbow machines in the Qin State were almost of the same specification, and the parts on one crossbow machine were broken, and they could be replaced with parts on other crossbow machines. It is this kind of sophisticated means that makes the military consumption of the Qin army far less than that of the six eastern countries, and finally wins the world! This is also the reason why the first emperor unified the world and unified weights and measures! ”

Li Shimin listened to it and praised it. And many ministers looked at Zhang Yunwen thoughtfully.

In the end, Li Shimin decided to implement new weights and measures next year, that is, the first year of Zhenguan, and make them mandatory throughout the country.

As a result, Zhang Yunwen's assembly line plan is expected.