"But Master, the reason why you can receive so much ship banknotes and trade taxes is thanks to the Royal Shipping." Jin Xuezeng is the most dishonest, and every time he speaks, he has a purpose. He pestered Zhao Hao and wanted to leave something. "After the Royal Shipping leaves next year, the county will have to be paralyzed. What infrastructure should we do?"

Now Xiaojin already knows that the Pudong New Area on the other side is under construction in full swing. It is said that the first phase of the year will be completed, and the Royal Shipping Port will be moved from Chongming to Pudong.

He finally understood that his master comforted himself to be strong... Last year he never dreamed that the mud pond in Pudong would snatch his golden rooster!

If I had known that, I would have to let my master agree to move out of the Royal Shipping a few years later.

"Don't come here." With a flap of his wings, Zhao Hao knew where he was going to fly, and said angrily: "Don't worry, the only thing you do is to get rid of your Royal Sea, and Sansha Pier will not be idle either."

But Zhao Hao didn't tell me what it was for, and he couldn't ask.

At this time, Chen Huaixiu came over to invite him to board his boat. Zhao Hao got rid of Xiao Jin's entanglement and followed Chen Huaixiu's Pingjiang.

As soon as he boarded the ship, the sailor brought the maritime weather forecast before departure issued by Chongming Meteorological Station.

"The next three days are sunny, the probability of rainfall is low, and the visibility is high at sea. The south wind in the Huangshui Ocean is level 3 to 5, and the light waves are light; the south wind or southeast wind in the Blackshui Ocean is level 3 to 5, and the light waves are to the middle waves, and I wish you a good journey..."

Chen Huaixiu sincerely thanked the meteorological and hydrology on the route in advance, which can greatly improve navigation safety and allow sailors to respond in advance.

In fact, the Pingjiang River also has various new instruments such as wind direction instruments, thermometers, hygrometers, flowmeters, etc. The sailors trained by the navigation school will read the numbers regularly every day and report real-time sea conditions and weather to the captain.

In addition, a series of navigation positioning instruments were added on the ship - sextant, two-leg gauge, protractor, and parallel ruler.

Some of these instruments were tinkered with Hua Shuyang and Bei Peijia, and some were used by Flang Jimen such as Pinto, Alfonso. Mr. Zhao integrated them. In the middle of the year, he went to Chongming Island Crew School to teach the usage of these instruments and related cartography knowledge.

The most critical sextant was something that Europeans did not have at this time.

The principle of sextant is not complicated. By measuring the angle between the sun and the sea level at a certain moment, you can quickly know the latitude at this time.

Even after the invention of radio positioning method later, Niu Zi's sextant invented was still widely used in navigation because of its fast and lightweightness.

However, the sextant made by Zhao Zi is far from being light. It is made of brass, like a large fan, weighing 26 kilograms, and the navigator has to fix its lower end to his belt to maintain stability.

This was what Mr. Zhao didn't expect at first. In his opinion, it would be easy to use the skilled craftsman of the Ming Dynasty to create a palm-sized sextant. How handsome is it to hang it around his waist?

But it can be made, but the measurement results are very inaccurate. Hua Shuyang quickly found the crux of the problem - although the principle of the sextant is very simple, it is essentially a protractor that measures the angle between two targets. However, its measurement accuracy is closely related to whether the scale is precise. At this time, the skilled craftsmen can carve the rice grains, but it is difficult for them to accurately divide the scales on small scale dials.

Therefore, you can only build it into a large area to improve the accuracy of the measurement. In the end, this sextant with an error of 0.2 degrees is created. If you hang it on the belt, you must pull off your pants.

Just be bigger, as long as it works. Mr. Zhao is already very content and ordered the two disciples to shift their research focus to longitude measurement.

In fact, the principle of longitude measurement is simpler. Forty years ago, Dutch astronomers proposed the idea of ​​"determining longitude by time" - since every 24 hours, the earth rotates one circle, that is, 360 degrees, which is equivalent to 15 degrees per hour and 1 degree in 4 minutes.

In this way, you only need to bring a very accurate clock to record the local time of the starting point, and use other methods to measure the local time of the current location. Then, through the difference between the two time, the difference in longitude between the two places can be easily obtained.

Zhao Hao knew that later generations used navigation clocks to determine the time of the departure place and used the "Astronomy Calendar" to determine the local time.

He thought that the difficulty lies in the latter, but Bei Peijia told Zhao Hao that the Imperial Heaven Supervision is specialized in this, and they will accurately record the records

The positions of various astronomical phenomena, sun, moon, planets and stars within a year are just needed to be transcribed into the "Astronomy Calendar" in a certain format.

In this way, the navigator only needs to go through simple calculations to determine the local time of the location based on the celestial phenomena of the location.

However, just when Mr. Zhao was about to announce happily that the location of Nanjing Purple Mountain Observatory was set as the prime meridian, Hua Shuyang told him that the principle of this method was correct, but it had limited effect in navigation.

The reason is that the most accurate Western clock is currently traveling, with an error of about five minutes every day. In that case, the actual error will exceed two hundred miles. If the captains rely on it to navigate, they will be tired of living.

Therefore, it is impossible to simply measure longitude with time before studying a more accurate navigation clock when leaving.

Therefore, the dream of sailing freely in the depths of the ocean without relying on the coast cannot be realized for the time being...

~~

However, the new navigation instruments in front of you are enough to make Chen Huaixiu admire him.

She held a two-legged rule in her hand and looked at Zhao Hao with admiration and said, "It's really unimaginable that a man who hasn't driven a boat for a day can invent so many new tricks, and each one is so practical, just like it has been tempered..."

"Haha, these are just simple measurements and calculations, and there is nothing wrong with those on sea and land." Mr. Zhao said, "It's of course. I'll get the navigation clock for you. You can use this set of tools until four hundred years later."

"For the master and apprentice, of course it's very simple." Chen Huaixiu frowned slightly, and said with a faint distress on her pretty face: "But for people like us who have not read books for a few days, those calculation formulas are even harder than the heavenly books."

"Be confident, you are no different from scholars." Mr. Zhao encouraged Chen Huaixiu and sarcastically said to the scholars: "If you really can't do it, just memorize it by rote and copy it by yourself. Sister Huaixiu is so smart, she must have mastered it long ago."

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"I'm just rote memorizing it..." Chen Huaixiu looked shy and showed a little childlike expression: "I understood at that time. I guess I will never be able to enter the science school in this life."

"I can't enter the front door, I'll just open the back door for you." Mr. Zhao couldn't help but smile.

"What nonsense..." Chen Huaixiu spat lightly, becoming more and more shy. Secretary Ma is still there...

The charming eyes were shy and closed, and the red lips were smiling. The wind rolled the grape belt, and the sun shone with pomegranate skirt.

These few lines of poetry popped up in Mr. Zhao's mind. This strong, intelligent, courageous and beautiful... especially the beautiful big sister, seems to have completely escaped the pain of losing her husband.

I am really happy for her. Purely happy...

For a moment, the atmosphere in the cabin was a little ambiguous.

Ma Xianglan's face was like an ancient well, as if she had heard nothing. She only held the folder with her hands and looked at the gradually moving Sansha Wharf without looking sideways.

But there is no intention to leave. Just behave if someone doesn't exist... as long as you can do it.

Chen Huaixiu coughed awkwardly, and quickly changed the topic: "By the way, these days when I went out to sea, I have all the clutchs with unknown origins followed me and watched them."

"Oh?" Zhao Hao indeed diverted his attention: "Didn't you grab a tongue?"

"They are all veterans of boat-fighting, and they are also flirting with four-oar sloops, and they are not close to us. As soon as our speedboat approaches, they immediately flew away, and the escort failed to catch it several times." Chen Huaixiu sighed lightly, then comforted again:

"But the problem shouldn't be big, our escort team is very strong."

According to Mr. Zhao's instructions, the Danluo Security District will double its troops within one year, and there are countless new police officers and warships that require nautical training.

Zhao Hao was also worried that the Portuguese or the southern sea owner would attack the Royal Marine fleet, so he simply asked them to be responsible for escorting the fleet, which could be considered a killing of two birds with one stone.

As for Chongming Island, there are two security brigades, a total of 1,000 security team members stationed, and more than 10,000 Sha Boat Gangs who receive regular military training. It shouldn’t be so stupid that they hit the stone with eggs, right?

"It's probably the sea lord in the south," Zhao Hao hugged his arms and thought for a moment: "These guys are like bloodthirsty sharks. When you smell the smell, come and explore the sound of the wind?"

In fact, it was mainly because he monopolized trade with Japan and did not allow ships of any other forces to approach Japan.

So, can’t Danluo Island take an overseas route and bypass the Seed Island controlled by the Jiangnan Group?

It really doesn't work.

Because in this era, ship navigation was very dependent on land. This is not only due to the need for ship replenishment and safety, but also for navigation.

Most of the sailors' ships are trapped in a voyage once they are away from land and have no coastline and known islands as reference points.

Therefore, at sea, there were only a few routes explored by our predecessors. As long as we guarded the key nodes, we would control the entire trade line.

At least the sea owners in the south do not have the ability to take foreign routes. The Portuguese walked by, but the sea lacked markers and reliable navigation instruments, and did not find suitable currents. The risk was too great to open up trade routes.

Without trade with Japan, not only the Portuguese were uncomfortable, but also the sea owners in the south. Of course, they had to find a way to pull out the nails and regain the route.
Chapter completed!