Besides, judging from the fact that both the emperor and his father agreed with Han Du to try this new strategy, Tang Ding felt that there should be no problem with Han Du's strategy.
The two wanted to say something more, but were interrupted impatiently by Tang He.
"Okay, stop talking. Get ready to sail."
At Yuwa's order, as the ropes were thrown down one by one, the warship was freed from its restraints. The tall sail was pulled up and the direction was slowly adjusted.
The majestic warship like a mountain, like a giant beast crawling on the water, began to slowly move out of the pond. Zuotang is directly connected to the Yangtze River, and warships enter the Yangtze River along Zuotang.
Relying on the fierce river wind, the warship headed straight for the mouth of the sea.
The departure of the warship naturally attracted the attention of the people on both sides of the Yangtze River. After all, such tall ships are rare, and there are three brand new ships. However, the Ming Navy had too many ships operating in the Yangtze River. There were only three ships, and dozens or hundreds more ships were dispatched together. The sight of masts blocking the sky and the sun was seen by the people countless times, and it was no longer surprising to the people.
After entering the sea, the warship was fully equipped with sails, showing the majesty of galloping freely. These three warships all use pointed bottom ship, watertight cabin, and balanced rudder technology. Once entering the sea, the speed is much faster than in the Yangtze River.
The sea was choppy, but on the warship it was like walking on flat ground.
Tang and Han Du even set up a low table, put a few dishes on it, and started drinking.
Taking a sip of the soup and wine, he asked Han Du thoughtfully, "How are you going to wipe out the Japanese pirates?"
Han Du put down his wine glass, glanced at Tang Ding, and said with a smile: "Of course the soldiers are very quick."
"What should I say?" Tang He asked thoughtfully.
Seeing that Tang Ding was here again, Han Du didn't mind spreading some things to him, so he said: "Above the sea, you can see everything at a glance. It is difficult for two armies to confront so many strategies, and there is no place to ambush. Unless it is like Where there is an island, otherwise once the two sides meet, the stronger one will win. However, as long as you are fast enough, you can retreat calmly even if you encounter a stronger one."
The most important thing is speed, Tang Ding nodded a few times.
"The other thing is that the ship is strong and the guns are powerful. There is nothing to say about this. You can take this opportunity to experience it." Han Du did not explain too much. This was originally proposed by me, and it has not been put into practice yet. It seems a bit excessive to say too much. It is better to let Tang Ding take advantage of this opportunity to see for himself.
Han Du took out something with a smile and put it on the short table.
Tang He saw the strange appearance of this thing and couldn't help but ask: "What is this?"
The iron thing is shaped like a fan, but it is completely different from a fan.
Han Du explained, "This is called a sextant."
"What's the use?" Tang He frowned and fiddled with it twice, holding it in his hand, but he didn't know how to use it.
"It's similar to a compass. It's used when sailing on the sea. A compass can point north and south, but this sextant can tell us where we are on the sea."
"You, are you telling the truth?" Tang He straightened his back. If what Han Du said was true, then the effect of this thing would be great. Why did the navy of the Ming Dynasty not dare to go deep into the sea to pursue Japanese pirates? Isn't it because once you go deep into the sea, it is difficult to determine where you are? How could he pursue the Japanese pirates if he didn't even know where he was?
As for why the Ming Dynasty was able to send ships to the Japanese country in the early years, it was because the Ming Dynasty knew in which direction the Japanese country was. As long as there was this compass to determine the direction and kept going, it would naturally be able to reach the Japanese country. The Japanese will not move, but the Japanese pirates will move.
"Of course," Han Du nodded, and then said, "But it's not that easy to determine the location."
Han Du spread out a map. Different from ordinary maps, this map was filled with thin lines that intersected vertically and horizontally.
"This is a newly drawn part from the whole map of the world. I drew these lines starting from the axis of the Chengtian Gate of the Imperial Palace."
Then Han Du taught Tang He how to use a sextant. He looked at the eyepiece, pointed the other mirror at the sun, and used the sea level as the benchmark. Turn the scale until the image of the sun appears on one side of the sea level, and then write down this. time scale.
"Is this how we can know where we are?" Tang He was confused and puzzled.
Han Du smiled and said: "Of course it's more than that. We also need to calculate a number, and then compare it on the map to roughly know where we are. However, the deviation in this calculation is still very large. If you want to be more accurate, One point, then we need to record the position of the sun every day of the year. The measurement on that day will be compared with the position of the sun on that day, so that it will be accurate after all. But now we don’t record the position of the sun. Therefore, we can only record one day at a time from now on.”
Tang He looked at the map, then picked up the sextant and tried it. He had to admire Han Du's ingenuity. At the same time, he shook his head and said, "We don't need to record it."
Han Du was stunned when he heard this. If we don't record it, who will?
Seeing Han Du's puzzled look, Tang He couldn't help but said, "Have you forgotten what the Qin Tian Jian does? Aren't they just recording the positions of the sun, moon and stars every day for hundreds of years? Do you want the position of the sun? There must be records in Qintian Prison, and they will not only have records from one year, but also from hundreds of years ago."
yes!
Why did I forget Qin Tian Jian? Thinking of this, Han Du felt annoyed. He should have thought of it a long time ago.
Tang He couldn't help complaining to Han Du, "You said you have some good things, but you like to hide them. Who would reach out and snatch your things? If you had taken this thing out earlier, I would have gone to Qintian The supervisor has brought the things."
Han Du disagreed with Tang He's statement that he would not steal anything. He robbed his own things, didn’t he rob enough? However, this matter is indeed due to Han Du's own shallowness. If you want to blame it, it is because Qin Tianjian's sense of existence is too low. Since Qin Tianjian was defeated by Han Jingyun last time, his presence has become even lower. Han Du didn't even take Qin Tianjian seriously. After all, there were so many people in one institution, but they couldn't compare to a girl who had only studied mathematics for a few months. What qualifications did Han Du have to pay attention to?
But Qin Tianjian is not only proficient in arithmetic. You must know that observing the stars is their duty. Arithmetic is just a tool to assist them in observing the stars.
But now, no matter what you say, it's over. The purpose of the warships going out to sea was to raid the Japanese pirates. Could it be that because of this, they could send people back to get the star records from the Qintian Prison before setting off?
Tang He sighed and had no choice but to say: "That's it, it's better than nothing."
"That's all it can do." Han Du gave an embarrassed smile. Han Du was so embarrassed that he almost dug out a three-bedroom apartment with his toes on the deck.
