Under the tree, Old Man Zhuo couldn't help but sigh in his heart.

"The talent of heaven and earth!"

These words are not used to describe them, but they are literal.

Coming from the ups and downs of the Hongwu Dynasty, Old Man Zhuo has never seen that such a talented person really exists in the world.

It's not just that the ideas in my head are uninspiring and eclectic.

And for the nature and principle of various things, he also has a very high ability to understand and control.

In Old Man Zhuo's opinion, Jiang Xinghuo's extremely smart brain is simply a treasure of infinite wisdom, which can make people easily find the answers they can't ask for.

"What's wrong with you, old sir?"

Looking at the old man Zhuo who fell silent beside him, Jiang Xinghuo was a little puzzled.

"Oh, it's okay, let's move on."

Coming back to his senses, Zhuo Jing waved his hand.

"Okay."

Jiang Xinghuo nodded and then continued to ask: "The determination of how to locate on the globe, that is, the determination of latitude and longitude, has been finished, is there anything else to ask?" There is no end to the class now. ”

After that, Jiang Xinghuo yawned, implying that he was sleepy.

No way, physics and mathematics are indeed easy to hypnosis.

Jiang Xinghuo looked down at the list of formulas listed on the ground, and he felt a little dizzy.

However, Jiang Xinghuo believes that the significance of this physics class is still very important.

There is no other reason, if you want to give Cheng Zhu Lixue a fatal blow, then Jiang Xinghuo believes that it is more appropriate to start from the perspective of "cosmology".

Why?

Because Cheng Zhuli's cosmology cannot be empirically proven.

In other words, they are all fanciful and cannot be verified.

And my doctrine that the cosmology can be proven, is naturally far stronger than the one that your cosmology cannot prove.

Again, practice is the standard for testing the truth of things.

My reasoning is here, and everyone can see it clearly.

Where is your reasoning?

Is there a heavenly principle that exists in nothingness?

Sorry, I can't see yes.

However, however, it was clear that Zheng He's hands holding his long hair were numb, and he was still in the mood to continue asking questions at this time!

Jiang Xinghuo was so sleepy that his brain hurt, but he had to bite the bullet and prepare to answer.

"And one last question."

Jiang Xinghuo sighed: "Just say it." ”

Zheng He also felt a little embarrassed, and hurriedly said, "It's really the last question." ”

"That's what I said." Zheng He cautiously owed, "Even if you can know the specific latitude and basically accurate longitude at sea, how can you determine where you are?" ”

Zheng He is very concerned about this issue, and the reason why Zheng He has to risk his identity being exposed and continue to ask these questions about navigation is because these questions are likely to save his life when he is in danger!

This is not an exaggeration at all.

In the rough ocean, positioning is more important than anything else!

But Zheng He went to sea, and so far he still uses the color eye people as the navigator.

That is to say, the core technology of navigation positioning is not completely in its own hands, and it takes at least a few ocean-going trainings to completely familiarize the Ming ocean-going fleet with the forbidden sea for many years.

Therefore, as the actual person in charge of the Daming Ocean Fleet, Zheng He is naturally a thousand and ten thousand concerned about this, even if his hands are numb at this time.

Hearing this question, Jiang Xinghuo couldn't help pinching his eyebrows, and asked rhetorically: "How do you measure speed when sailing now?" ”

Zheng He said truthfully: "The driftwood method is used. ”

"Tell me."

Jiang Xinghuo is not omniscient and omniscient, and some of them still don't know much about the specific principles of ancient Chinese ocean navigation technology.

After Zheng He's explanation, Jiang Xinghuo understood what this "Flowing Wood Method" was all about.

"Driftwood method" first originated in the Three Kingdoms era, when the sea ships of Wu State have been able to reach the area of Wanli Shitang, the people who accompanied the ship wrote the book "Nanzhou Foreign Matter Chronicles", there is such a record in the book: put a piece of wood into the sea on the bow of the ship, and then run quickly from the bow to the stern, by seeing whether the wood chips arrive at the same time, to measure the speed and range, that is, the prototype of the "driftwood method".

And to today's Ming Dynasty, the use of this ancient method, only a slight improvement, that is, to divide the day and night into ten watches, by burning incense to time, or to throw the wood into the sea, and then people to run, if the arrival at the same time is considered the standard, and if the person arrives first can not be called, the wood chips arrive first to call the change.

The distance of each is fifty miles (some say sixty miles), so that the speed and range of the ship on the ocean can be calculated.

The advantage of the "Driftwood Method" is that it can measure distance and measure speed.

The disadvantages are. It's a bit of a waste.

After listening, Jiang Xinghuo said in a deep voice: "Let me give an opinion first." ”

"Mr. Jiang, please advise."

"I can't talk about advice." Jiang Xinghuo smiled bitterly, "Don't you think this speed measurement method is a bit wasteful?" And, what if the waves are big? Planks or blocks, chips of wood, etc., won't a wave be lost? It can't always be calm for you to observe. ”

Zheng He was also a little helpless, and only said: "It has been like this since ancient times, and there is no good way to improve it." ”

"You can use the knot method." Jiang Xinghuo said.

Zheng He was stunned when he heard this, what is the knot method?

It would be great if the knotting method mentioned by Mr. Jiang could avoid the drawbacks of the driftwood method not being able to adapt to complex sea conditions.

After all, there are people on the boat who can turn back and run, but the wood cannot float smoothly from the bow to the stern in complex sea conditions, which is the biggest disadvantage of the driftwood method.

Therefore, Zheng He sincerely hopes that Mr. Jiang can come up with a better way.

"The first one is that you don't need to use incense sticks to time, you can use an hourglass, not necessarily a glass hourglass, and others can also be used."

Speaking of hourglasses, also known as "sand clocks" in ancient China, the manufacturing principle is roughly the same as that of water droplet leakage, and the time is also measured according to the number of leaks from one container to another.

And the reason why there is a water drop leak and the hourglass is invented is because the weather is cold in the north in winter, and the leakage is not used at all, and it will freeze at every turn.

At this time, the Ming Dynasty, not only has an hourglass, but also has a very well-made variety, called "five rounds of hourglass", which is the Hongwu Dynasty's Zhongshu Sheren, the pioneer of the Taige style, and the early Ming Dynasty book saint Zhan Xiyuan invented.

The quicksand of this "five-wheel hourglass" flows from the funnel-shaped sand pool to the sand bucket on the side of the primary wheel, drives the initial wheel, thereby driving the mechanical gears of all levels to rotate, and the last gear drives the middle wheel that rotates on the horizontal plane, and there is a pointer on the axis of the middle wheel, and the pointer rotates on an instrument disc with a carved line, so as to display the time, this display method is almost exactly the same as the surface structure of modern clocks.

In addition to this, Zhan Xiyuan also cleverly added a mechanical toggle device to the middle wheel to remind the two wooden figures standing on the five-wheel hourglass to beat the drum to tell the time. Every hour or hour, two wooden figures will come out on their own and beat the drum to report the time. This hourglass has become a mechanical clock structure in its own right, separated from auxiliary astronomical instruments.

Belch. In fact, when I think of Zhu Yuanzhang's angry smashing of the glass astronomical, I can also think of what the ending of this brother who loves to invent is.

- was given by Lao Zhu.

Oh yes, Zhan Xiyuan also has a disciple named Xie Jin.

In short, Daming has an hourglass, and there is no doubt that it has a good hourglass.

"The second, the knotting method itself, means that while the hourglass is timed, a rope tied with a colored triangular plank is thrown into the sea, and the rope is knotted at fixed distances, and the other end of the rope is wound around a spindle-shaped receiver, and as the ship moves forward, the rope keeps coming out of the receiver and passing through the sailor's palm, and with the end of the fixed time, the sailor reports the number of knots that pass through the palm of his hand during this fixed time, and this number is divided by the time that the hourglass has passed. The result is the speed of sailing. ”

"In this way, the calculator knows this speed, and according to the direction of the voyage, he can indicate the current position of the ship on the chart."

Looking thoughtfully at the red-faced man, Jiang Xinghuo said.

"In the same way, this fixed knot method can also use how many knots as a fixed mileage, so that on the map, the latitude and longitude can also be delineated."

Zheng He only understood at this point, but his face became more and more red with excitement, and he repeatedly expressed his gratitude to Jiang Xinghuo.

Jiang Xinghuo's method, although it doesn't sound like a big deal, for Zheng He, it is tantamount to solving a huge practical problem.

After all, the difference in practicality between the "quickwood method" and the "knot method" can be realized by anyone who has only heard it once.

The "knot method" can not only measure the distance stably, but also ignore most ordinary sea conditions, and from then on, Zheng He had nothing to fear.

Thinking that he had received Mr. Jiang's guidance, and from now on he could lead the invincible Ming fleet across the world, Zheng He's heart became more and more excited.

Jiang Xinghuo concluded: "The starry sky is boundless, the sea is endless, but what I want to say is that as long as we use scientific methods, we will definitely be able to do something that cannot be done in traditional concepts." ”

Jiang Xinghuo looked at the sky and felt a feeling for a while.

"Although people have to take care of the current situation, they must never forget the stars and the sea in their dreams."

"Let's get out of class!"

A few people got up, and Old Man Zhuo's thoughts drifted to another place.

Zhuo Jing looked at the sky from afar, looked at the sun hidden in the clouds, and after listening to Jiang Xinghuo's lesson, a huge sense of ambition and pride suddenly rose in his heart.

The old man chats about hair, the boy is crazy!

If he agrees to Daoyan's conditions, then it seems that he can't participate in this unprecedented "measuring the sun and moon, passing through the heavens and latitudes", which has never been seen before or since?

Thinking like this, Old Man Zhuo was leisurely fascinated.

If only it could be done.

(End of chapter)