The gains and losses of Hezhou and the approaching solar eclipse made Wang Anshi finally make up his mind. Regardless of the objections of Lu Huiqing and others, he petitioned Zhao Xu to request adjustments to the new law.

On Bingchen of the third month, Si Tianjian said that on the first day of the fourth month, the sun would eclipse at nine points.

The imperial edict came from Ding Si who had taken refuge in the palace and reduced his meals. He was sentenced to the highest level of imprisonment in the world, and he was exonerated by being exiled.

The principal and interest money owed by the landless households in the world for the young crops loan will be waived, and the money for labor service will be waived.

Lu Jiawen petitioned to establish the Shiyi Debian Office to recover the principal and interest of the Shiyisi loans owed by each household.

Su You petitioned for a delay, and also requested that the power of the Director of the Trade Exchange be divided.

Xue Xiang's impeachment of the City Council resulted in huge losses for the wineries in Bianjing. Twenty-seven wineries were on the verge of bankruptcy. The combined losses of both the winery and the wine shop amounted to one million guan; this year, Bianjing will face an unprecedented crisis.

Go to the wine shop, there will be no wine left in the wine shop, and there will be no wine to drink in Bianjing.

Just when the Mingtang ceremony was completed, a minister mistakenly moved Xue Xiang to the right to admonish the officials. Zhao Xu punished the officials, but did not take away the old man's promotion, and asked Wang Anshi to find another candidate for the third minister.

Wang Anshi recommended Zeng Bu as the Third Secretary and asked the Municipal Yi Department to suspend business while Zeng Bu investigated the situation.

Lu Jiawen believed that he should be the third envoy, which was a great injustice.

…

In front of the Kaifeng government office, the prison was opened wide, and hundreds of people who were caught here in debt were all released by Su You.

While in detention, Su You asked the prison officer Shen Chen to organize the prisoners to clean up, clean up the prison environment, disinfect and kill insects, bathe and cook clothes, and then treat the sick ones without losing any lives.

The common people were so grateful that they knelt on the ground in the school grounds and wanted to see the governor.

Su You had no choice but to come out and comfort them with soft words, asking them to go home and make a living. Soon the court should make adjustments to the affairs of the Municipal Yi Department. Please trust the government.

Once the prison was empty, Kaifeng Mansion's young Su Qingtian's reputation resounded throughout the city.

The younger sister came out of the palace and said that the empress dowagers of the two palaces were very pleased with the way he handled the Xuandemen case and the way the City Yi Division owed money to the people.

Su You looked at his little sister's belly: "You should stop worrying about these things. Jingrun is too busy in Zhengzhou. I will transfer him back to be a young prisoner. How about you resign as the mountain chief?"

The younger sister said: "The Queen Mother said that they would not be worried if it were anyone else. After all, I am a woman and I will not become an official."

Su You was anxious: "Then I'll go tell the Queen Mother."

The younger sister pulled Su You's sleeve: "No, the Queen Mother has granted me a year's leave and asked Zong You to take over temporarily."

Su You was speechless: "Zhao Zongyou, he is still a child..."

The younger sister smiled and said, "You are seventeen, so you are not considered a child. Brother, please find something for me to do. I am almost bored to death."

Su You thought about it and said: "It's really something. The Japanese officials in Sitianjian have long lost the skills of their ancestors, and they are all selling mediocre goods. Dharma images, diagrams, armillary spheres, landscape tables, and five pots and leaks.

Nothing."

"Depending on them, I think this head will be taken away by His Majesty and used as a specimen sooner or later."

The little girl chuckled: "Then what do you want?"

Su You touched his chin: "I want those people to hand over all the ancient books that have been handed down from their families, and then find someone to translate them into reference books using the writing methods of science and engineering. If nothing else, based on the accurately calculated precession, we will then backtrack the three thousand years of Chinese history.

The records of lunar eclipses and the movements of the five stars are big things."

"After that, we need to make a map of the country, make star maps, precise measuring tools, modify astronomical observation instruments, and compile an accurate calendar... Most importantly, my brother wants to create an artifact that can measure time mechanically."

The younger sister said, "Zhaoming should be able to help."

Su You said: "Yes, I am going to report to Your Majesty to recruit Taishi, divination, and miscellaneous scholars from all over the world. They will be divided into five subjects, but it is different from the past. It will be divided into five categories: calendar, astronomy, geography, arithmetic, and instrumentation."

"I originally wanted to ask my clan uncle to come back and take charge of this matter, but Wang Xianggong refused. Therefore, I can only take charge of the matter, and then invite Jingrun, Cunzhong, Shi Lao, Wei Lao, Qiuguan Huangfu Yu, recommended by clan brother

Instrument master Han Gonglian worked together to tackle the problem."

"There is also the Tianshi Mansion. You and the two foreigners from Tianfang are also involved."

The younger sister nodded: "Well, if a group of us can't come out, no one in the world can do it."

…

Si Tianjian, in charge of observing the astronomical auspiciousness, engraving bells and drums, writing almanacs, offering sacrifices to the altars, announcing the names of gods, and painting dates.

China is an agricultural civilization, and solar terms are particularly important to this country.

Therefore, the most important job of Si Tianjian is to accurately tell the time, confirm the solar terms, and predict possible weather changes.

Due to the precession of the equinox, there will be an error between the actual solar year and the calendar year. Therefore, after a period of time, the old calendar error accumulates too much and needs to be revised.

In fact, as long as the error is accurately calculated and accurate observations are made, the problem can be solved through adjustments.

But the problem is that after the calendar is established, the rulers will consider it a great achievement of the country and generally cannot be easily modified.

In addition, the amount of calculation is very huge. In the past, calculations were used, and the writing method was cumbersome. The lack of statistical lists would lead to a huge workload and calculation errors.

Therefore, in general, calculation and verification are divided into two departments, accounting for two-fifths of the total manpower.

The so-called precession refers to the long-term precession of the earth's rotation axis, which causes the vernal equinox to move westward along the ecliptic, resulting in the tropical year being shorter than the sidereal year.

The reason is that the earth is an ellipsoid, with the equatorial part bulging; the equatorial plane does not coincide with the ecliptic plane.

The sun, moon and other planets exert additional gravitational pull on their equatorial bulge, causing changes in the inclination of the equatorial plane, which is the precession of the earth's axis.

As a result, the vernal equinox moves westward along the ecliptic by about fifty minutes and two seconds every year, or about one week in 26,000 years.

Because it makes the tropical year slightly shorter than the sidereal year, it was called "precession" in ancient China.

The westward movement of the vernal equinox caused by the action of the sun and the moon does not change the ecliptic angle, which is called "solar and lunar precession"; the action of other planets changes the ecliptic angle at the same time, which is called "planetary precession". The sum of the two is called "precession of the planet"

Total precession”.

However, the influence of planetary precession is very small, and the main consideration is the precession of the sun and the moon.

In the fourth century AD, Yu Xi, an astronomer from the Jin Dynasty in China, while analyzing ancient star charts and starry skies, discovered that the positions of the stars in the Jin Dynasty were slightly shifted from those in ancient times. He then discovered the precession of the equinoxes and left the winter solstice points every fifty years.

A record of moving back one degree.

"History of the Song Dynasty·Lü Li Zhi" records: "Yu Xiyun said: 'In the time of Yao, the short star Pleiades on the winter solstice has been on the east wall for more than 2,700 years, and we can know the difference every year.'"

This is where the term precession comes from.

The great astronomer Zu Chongzhi introduced precession into calendar calculations for the first time in the "Da Ming Calendar" formulated in 463 AD.

Some astronomers previously believed that the sun returns to the starting point of the previous year after each tropical year on the ecliptic.

After careful observation, Zu Chongzhi believed that the winter solstice moves back one degree every forty-five and eleven months.

This makes the Daming Calendar more thorough than other calendars.

However, the error between this value and the actual precession is still not small. In addition, later generations did not understand the basic principle, which led to the "Da Ming Calendar" being abandoned a long time later due to excessive accumulated errors.

The Chinese calendar is a combination of the solar calendar and the lunar calendar, so several key data determine whether the calendar is accurate.

In Su You's eyes, since Zu Dada's Ming Calendar has used precession to solve the problem of calendar accuracy; it can also propose a new leap week with 144 leap months in 391 years, which is better than seven leap weeks in 19 years.

The leap week is more precise; he also calculated that the length of a tropical year should be 365.2428 days, accurate to four digits after the decimal point; then modern people should be better than the ancients.

The same principle solves the problem of the length of a year and the precise measurement of the winter solstice, which is related to the starting point of the calendar.

In the past, measurements were made using standard gauges.

The ancients used the Gui watch to measure the length of the shadow at noon every day, which can directly determine the date of the winter solstice, because the day with the longest shadow at noon in a year is the day of the winter solstice.

However, there is a huge error in this thing, as large as one or two days, so the impact of this error must be greatly reduced through the accumulation and averaging of long-term observation data.
Chapter completed!