[I went out at night, I'm sorry to be late]

"This is the waterway chronometer?"

Han Gang, who was invited by Su Song, came to Si Tianjian's courtyard in a corner of the inner city.

Outside the wall is the gurgling Jinshui River, a tributary of which runs into the basement of a pavilion behind the courtyard.

"It's the water timetable." Su Song proudly introduced to Han Gang.

Han Gang looked up, he knew that this water transport timepiece table, in the original design, should be called the water transport instrument elephant platform.

As early as the time of Renzong, Su Song once intended to build a ceremonial platform driven by water power.

In his design, the top part of the armillary sphere is used to observe the night sky, and the top of the armillary sphere is designed with a roof that can be opened and closed freely to protect it from the sun and rain.

The next layer of the armillary sphere is the armillary image, which symbolizes the celestial sphere and demonstrates the motion of celestial bodies. In Su Song's design, half of the celestial sphere is hidden under the "horizon", and the other half is exposed above the "horizon", which is driven by the wheel of the machine to rotate, turning one circle day and night, truly reproducing the changes in the sky such as the rise and fall of the stars.

The next level is the timepiece, which reports the time on time. At the bottom is the machine qì that refers to hydraulic power, which drives the entire instrument and elephant platform through guò hydraulic power.

However, in the school of qi science, the armillary sphere was thrown into the cold palace, and the telescope eliminated the old astronomical instruments and became the new darling for observing the sky.

Therefore, the armillary sphere that Su Song wanted to create became a waterborne timepiece table. There are also instruments for observing astronomy, but they are telescopes with fixed angles. According to him, it is necessary to compile a star catalog to determine which star will be seen at what time of the day, and thus determine the time.

Su Song's idea was very interesting, but Han Gang felt that without thirty or fifty years of continuous observation, even the orbital tables of planetary satellites and solar and lunar eclipses might not be able to be successfully compiled, let alone time them through the stars. But astronomical observations are necessary, and without Tycho, there would be no Kepler's Three Laws of Planets. Observing the universe and understanding the universe requires decades or hundreds of years of continuous observation, so Han Gang will not pour Su Song's cold water, but look forward to it with admiration.

Today, the scale of this waterborne timepiece is like a small building, almost three stories high. Walking into Taichung, a staircase connects up and down, and there is the sound of flowing water and the sound of the machine turning.

The flow of water under the feet drives the mechanism in the watchpiece, and the gears carry the water up and guide the timepiece to the corresponding position.

This may be the world's first mechanical clock. Han Gang thought. He didn't know whether the West had invented clocks or not.

But in medieval Europe, in the mouths of the great food merchants who came to China, it was a poor country worth mentioning, the territory of barbaric and poor and untrustworthy pagans, and when they spoke of Greece and Rome with nostalgia, they all laughed at the ignorance of Europeans at this time. I am afraid that even if the Europeans invented the mechanical timepiece, it would be overshadowed by Su Song's current invention - with the current situation in the Great Song Dynasty, Su Song's invention of the timepiece would soon spread all over the world.

The flow of water through guò steady dìng determines the passage of time. Therefore, the most difficult point of the waterborne timepiece is how to ensure the stability of the mechanical operation.

Su Song personally designed the mechanical structure of the timepiece, through a special wheel and gear lever structure, so that the water flowing down from the upper bucket drove the gears to rotate steadily, and the water flowing down was then sent back to the upper bucket through the turbine at the bottom of the guò floor. Although it may seem cumbersome, this is a cross-generational technology.

Han Gang raised his head and looked at this huge timepiece table, at the beginning, he would not have thought that Su Song would be able to make a machine as big as a house, and someone would have to maintain it here anytime and anywhere, the cost of using it was too amazing, only the public money of the imperial court could afford such utensils.

However, the water transport timepiece that had just been built was not the reason why Su Song invited Han Gang to visit Si Tianjian, what he wanted to show was not this timepiece, but the timepiece placed in another room.

In another room, there was a table clock more than one person high, and the shorter ones could not stand on tiptoe at the top of the table. It's just that if you put this clock next to the water transport timetable outside like a small building, it is a comparison between a kitten and a tiger.

Above the front of the clock is a dial with three hands at different ends, and a glass door below, behind which the pendulum is swinging smoothly.

The pendulum of the pendulum looks like a bone in Takeo's hand, and its shape is almost identical, only flattened and wide. The pendulum attached to the pendulum is elongated.

The origin of the pendulum clock was discovered by Galileo in another world, but here it became the principle proposed by Han Gang. So Su Song happily came to Han Gang after his success and thanked him for discovering the meaning of the swing.

The pendulum always oscillates at the same time, and as long as it is transmitted to the hands through the guò gear link, it is a standard clock. The remaining problem to solve is how to keep the pendulum swinging.

A moment, a moment, a day, a month, a long swing, this is the most difficult step.

Neither human nor animal power can do this, and the current steel technology is still a long way from elastic springs, and of course it is impossible to achieve it. When Han Gang was helpless, Su Song, who was designing a water-borne timepiece table, naturally thought of using water power. That's why the table clock has been designed and developed in conjunction with the water timepiece table.

But in the end, Su Song finally discovered that the table clock did not need any water power at all. As long as a heavy hammer is made, a long rope is tied, and then this rope wrapped with silk thread is wound around a pole extending from the center of a gear, under the influence of gravity, the hammer keeps descending, driving the gear to rotate, which is the ready-made power. The gears drive the gears, and the power is transmitted at the first level, through a small escapement, which replenishes the energy lost in the movement of the pendulum and ensures that the pendulum continues to run. All one has to do is to re-wrap the hammer around it every few days.

The hammer is used as a power drive, which is just a layer of window paper, and the rest can be done immediately with the existing technology. But when Han Gang was ignorant of this and couldn't come forward to give advice, Su Song and his skilled craftsmen, who already understood the principle of the pendulum, just took a full five years to make a detour.

"What is the error of this timepiece?" Han Gang looked the clock up and down for a while, and then asked.

Although it is clearly a pendulum clock in front of him, it will not tell the time when it is punctual, so Han Gang can't casually say a table clock or pendulum clock, but can only call it a timepiece. In the future, it will be placed on the bell and drum tower, or in the center of the city, a huge bell tower with dials and hands will be built, and the bell will be linked on time, and then it will be called a pendulum clock.

"Every day?" Su Song asked.

Han Gang nodded, "It's just a day's error." ”

"About a quarter of an hour."

Han Gang almost choked, this is an extremely exaggerated proportion, but this is a new thing after all, and he can't be blamed.

"The error of the waterborne timepiece table is a little better, only one minute a day."

With a mechanical timepiece, there is a need to divide the hours, minutes and seconds, Han Gang put forward his opinion to Su Song, and Su Song happily accepted Han Gang's idea. Dividing an hour into two hours, the beginning and the main hour, such as Zichu and Zizheng, and then dividing the hour into sixty minutes and the minute into sixty seconds, is in line with Han Gang's habit.

"What if you stop in the middle of the winding?" Han Gang asked again.

Su Song said: "It can be calibrated with a water transport timepiece table. ”

"That ......"

"If the water-borne timepiece table is broken, calibrate it with a pendulum timepiece." Su Song smiled at Han Gang, he knew what Han Gang wanted to ask, "If both timepieces are broken at the same time, they will be calibrated with a sundial in the end." And every day at noon, it will be adjusted according to the sundial. ”

Every day at noon, the sun is due south, and the origin of the definition of the day is, of course, the hallmark of the calibration of all the timekeeping instruments. Therefore, the sundial is the most accurate timepiece in the world.

Han Gang can rest assured, there will be no joke that the bell ringer rings the bell according to the timed cannon, and the cannon shooter fires the cannon according to the bell ringer's bell.

Compared with sundials, the accuracy of pendulum clocks is still far behind, and even less than the leakage. But then again, this is already a pleasant start, so there's no need to be too demanding. Good and bad aside, whether there is or not is the most important thing.

Just like a three-story small building, it is impossible to promote the water transport timepiece table to the people, but the pendulum clock is completely possible, and now there is finally a clock with promotion and utilization value, which is the goal that Han Gang has been looking forward to achieve.

Han Gang praised repeatedly, Su Song was very satisfied with Han Gang's reaction, and said with a smile: "Yukun, don't worry, I will try my best to be more accurate below." ”

"That couldn't be better." Han Gang couldn't wait to rub his hands and said to Su Song, "It's a waste of too much time to schedule the departure of the train with a leak now." If a more accurate timepiece could have been used, the frequency of departures could now be increased by at least half. ”

Su Song's expression was radiant, his eyes burned, and he couldn't see it at all when he was in the court, "In other words, there is more than half of the railway coming out?!" ”

"As long as the horses can keep up, a railroad might be possible." Han Gang shook his head and sighed, "It's just that there are more than fifteen thousand horses of all kinds used on the railways that are already in operation today, and more than half of them need to be increased by at least one million bunches of forage." ”

"A million bunches of grass, if it's alfalfa, it's almost 500,000 acres of fields!" Su Song sighed.

"It's hard to find so many fields."

The hay that can be produced in one acre of land is only two or three bunches. Using 500,000 acres of land to grow grass is a huge amount even if it is not good land.

"Let's go find the new county king of Da Liao, it's impossible to use a horse." Su Song said with a smile.

Han Gang laughed and spread his hands, "Then we have to wait for someone to invent the steam engine first, and then go to the emperor of the Liao Kingdom." ”