Chapter 514: Weights and Measures

The news that the Anxi Protectorate had recovered the Khorasan region of Persia was sent back to Chang'an. Li Chengqian was very happy and rewarded them greatly. He

also set up a governor's office in the Khorasan region, with Peroz as the first governor of Persia. The governor's office was different from the Protectorate and the Governor's Office. It had autonomy, but was restricted by the Protectorate.

The envoys of the Arabs came to Chang'an and met with Li Chengqian. They brought Kharifa's intentions and presented treasures to show their sincerity. From then on, the Arabs and the Tang Dynasty became brotherly countries.

Li Chengqian originally planned to send troops to attack the Arabs, but then he thought that the battle line was too long and supply was difficult, and the Arabs were now powerful.

If he fought it to the death, it would only drag down the economic system of the Tang Dynasty, and the gains would not make up for the losses. Doing so might also allow Tubo to take advantage.

Even though Tubo's strength was seriously damaged, once the Tang Dynasty's strength was seriously damaged, Tubo would likely make a comeback.

After repeated considerations, Li Chengqian finally decided to agree to negotiate peace with the Arabs, acknowledging that except for the Khorasan region, all other areas that did not belong to the Tang Dynasty belonged to the Arabs.

The territories that were occupied by the Arabs and originally belonged to the Tang Dynasty were returned to the Tang Dynasty. The Tang Dynasty and the Arabs signed a brotherly alliance and conducted trade exchanges.

"Everyone! The Minister of Works has handed over a memorial, please take a look." Wang Quan handed a memorial from the Ministry of Works to Li Chengqian.

"This memorial will be sent to the East Palace first, and let the prince take a look first. After trying to deal with it, bring it to me to see." Li Chengqian said.

It's time to test the prince's ability to govern the country. Let him handle some government affairs first, and then I will instruct him on what to do correctly.

"Yes!" Wang Quan took the order, picked up the memorial on the table, called an eunuch, and asked him to deliver the memorial to the prince in the East Palace.

After reading the memorial, Prince Li Jue summoned the officials of the East Palace to discuss it, and then made comments on the memorial and sent it to Li Chengqian. After Li

Chengqian read Li Jue's comments, he ordered someone to call Li Jue to the Purple Palace for questioning.

"Your son has seen the emperor!" Li Jue saluted.

"No need to be polite! Sit down!" Li Chengqian said.

"Thank you, father!" Li Jue thanked him and sat down.

"I have read your comments on the memorial submitted by the Ministry of Works. You have already read the memorial of the Ministry of Works. Do you think the things raised by the Ministry of Works do not need to be changed?" Li Chengqian asked.

"The Ministry of Works said in a memorial that the current weights and measures are not precise enough and are not suitable for the production of precision instruments in the Tang Dynasty. They requested that the weights and measures be revised."

"The current weights and measures were revised during the reign of Emperor Taizong. I and my subordinates think there is nothing wrong with them. Therefore, I think there is no need to revise any weights and measures. Just use the original ones." Li Jue said.

The so-called weights and measures actually refer to the instruments used to measure length, called degrees, the vessels used to measure and calculate volume, and the tools used to measure the weight of objects, called scales.

The length of the Tang Dynasty was based on the double steps of Emperor Taizong (one step for each left and right foot), called "bu", and 300 steps were stipulated as one li. One fifth of a "bu" is one chi.

Ten feet is one zhang, one thousand five hundred feet is one li, and other weights and volumes have corresponding units, such as sheng, dou, hu, shi, etc.

Compared with later generations, there are some deviations. In later generations, one li is equal to 500 meters, but in the Tang Dynasty, one li is only 454.2 meters, which is 45.8 meters shorter than 500 meters.

In fact, the current measurement method is still acceptable and does not need much change.

However, the length of the ruler in the Tang Dynasty was between 28 cm and 31 cm.

The scale measured in this way will have some deviations, so Li Chengqian decided to unify the length of these measuring rulers.

"Nowadays, the north and the south are different, and the length of rulers in different places is different. What's more, the length of people's steps will also be different."

"So, I decided to set the length within a range and no longer use steps to measure length." Li Chengqian said.

The length standard of later generations is good. Li Chengqian plans to follow the length, area, capacity, etc. of later generations, and even change the time to a 24-hour system.

"How does father plan to change it?" Li Jue asked.

"Let's change the current time first. We used to use twelve hours a day, but now we change it to twenty-four hours a day." Li Chengqian said.

"Twenty-four hours?" Li Jue asked in confusion.

"Yes, twenty-four hours, that is, divide one hour into two hours, one hour equals sixty minutes, and one minute equals sixty seconds. If we use all numbers, it will be much more accurate." Li Chengqian said.

Li Jue thought about it and realized that it was indeed much more accurate than using twelve hours.

"But father, how can this be applied to real life?" Li Jue asked.

Yes, now is not like the later generations, where there are clocks to calculate time. There is no such thing as clocks in the current Tang Dynasty.

"I have already thought about this and have my own way to deal with it. You will know when the time comes." Li Chengqian said.

The calculation of time can be solved by using an hourglass. This is not a problem at all. The hourglass leaks out exactly one minute.

The time problem has been solved. Now it is a length problem. Fortunately, Li Chengqian has been prepared and has made a length standard.

"The next thing is the length. The basic length is defined as one meter. One meter is divided into ten parts, each part is a decimeter. One meter is equal to ten centimeters, and one centimeter is equal to one millimeter."

"One li is unified as 500 meters. 1000 meters is equal to one kilometer, which is two li. This way it will be more accurate." Li Chengqian said.

In this way, there will be no deviation in measuring land in the future, and it will prevent anyone from making a fuss about it.

After hearing this, Li Jue also felt that this calculation was more accurate. This way, the length was unified and it was not so confusing.

If the unit was a step, there would be deviations due to the different sizes of individual steps. Now that the length is the same, there will be no errors.

"The next question is about weight. We can first make a box that is 10 centimeters long, wide, and high, and fill it with water. We can define it as one kilogram, which is 2 jin, equal to 1 kilogram."

"We can define 1 liang as 50 grams, and 500 grams equals 1 jin. What do you think?" Li Chengqian asked. "

I think it's feasible. This way it will be simple and convenient. Not only the length and time, but also the weight can be more accurate. But how to convert one stone now?" Li Jue said, and raised his own doubts.

"It's very simple. Convert one stone of grain into 120 jin. All other liters and dou! Convert them all to the new calculation method and discard the original ones." Li Chengqian said.

"Now, I know what to do!" Li Jue said.

"Well, since you know what to do, I'll leave this matter to you," Li Chengqian said.

"Yes! I'll take my leave!" Li Jue bowed and left.