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Wang Junlin followed Du Haiwa's example, staring at the stars in the sky for a long time, only to feel that his eyes were sour, and those stars were also confused with each other, and it was not easy to distinguish them one by one.

He knew that Du Haiva was using the "art of pulling stars" to tell the direction, and sometimes Du Haiva would look at the compass fixed in front of him.

For Du Haiwa, although the galaxy in the sky is incomparably vast, the stars are as innumerable as grains of sand in the eyes of others, but in his eyes, they are as familiar as the palm prints of his palms.

"That's the Big Dipper."

Du Haiwa watched while making sure that there was no problem with the direction of the sea boat, and then he would point out to the officers and soldiers of the sailor division next to him, in fact, Du Haiwa was already a regiment leader in the sailor, with 500 subordinates, and there were 4,000 sailors sent to the two islands of Xinde this time, including four captains, eight regiment masters, forty hundred commanders, and two hundred fire commanders, so the regiment owner was also a senior general.

"You see, what does this Big Dipper look like when they are connected together, it doesn't look like a spoon used to drink soup."

"That's right, it's like a spoon." After taking a closer look, everyone nodded their heads.

Duhaiva raised her hand and pointed to a line of stars in the sky, drawing dotted lines with her fingers, connecting them, and calling out their names one by one.

"Following the direction of my finger, these seven stars are called Tianshu, Tianxuan, Tianji, Tianquan, Yuheng, Kaiyang, and Yaoguang, these names don't need to be remembered, but this shape must be memorized, at least it must be immediately distinguishable as soon as you look up."

After everyone nodded yes, Du Haiwa said again: "Look again, there is a straight line between Tianxuan and Tianshu located on Doukui, and then extend the distance in the direction of Tianshu by 5 times, and you can find an extremely bright star that eclipses the stars. ”

Everyone took a closer look, and they suddenly realized that it was, and they claimed that it had made this dead sea more vibrant.

"That is the North Star, where it lives and all the stars are together, and the ultimate purpose of our recognition of the Big Dipper is to accurately find out this North Star, and then confirm the location of the North through the North Star."

"I see." Zhang Tiangang, who was listening to the fascination next to him, suddenly realized.

The sea is vast, boundless, I don't know anything, there is the sun during the day, but at night, you have to rely on the stars. Polaris, which is the natal star of every navigator, is located at the North Celestial Pole, the position is almost unchanged, and it can be relied on to discern the direction, and the "astrological technique" that Du Haiwa wants to teach everyone, around the North Star to perform calculations, is the most commonly used method.

"At this time, there is no moon to compete for light, and there are no clouds to obstruct, it is a good time to perform the astrological technique, the method I taught you the day before yesterday, everyone try to test it."

Wang Junlin is on the big ship, in addition to his 100 guards, there are 400 officers and soldiers of the sailors, according to the basic requirements of Wang Junlin's series of sailors, if you want to become an officer above the regiment leader, you must learn the art of pulling stars, and now you have the opportunity to be taught this technique by Du Haiwa, who is the most proficient in the art of pulling stars, and the four hundred captains and a group of fire commanders on the ship have studied very seriously.

Each person is holding a "star-holding board", which is made of peach wood, a total of thirteen pieces, together like a fan, the largest one is thirteen fingerboards, and the smallest one is one fingerboard. Of course, this star-holding board came from Nie Xiaoyu's handwriting, originally she had more advanced things, but she was limited to the poor knowledge level of people in this era, and she couldn't understand it at all, so she re-researched and formulated such a relatively simple and easy-to-learn, and easy-to-operate star-holding board.

The Hundred-Captain and the Fire Commander are no strangers to the star-holding board, they have already been trained when they were on Snake Island, at this time they hold the center of one end of the star-holding board in their left hand, and look at the starry sky with their arms straightened, so that the surface of the star-holding board is perpendicular to the sea level, and observe the height of the North Star from the sea level. Depending on the height, it can be adjusted with thirteen planks.

Next to each of them, there were two sailor soldiers as assistants, one holding a fire for lighting, and the other writing down the observations for him on paper.

It was not easy to complete the measurement on the rickety deck, but after the measurement, the group returned to the cabin, and according to the measured altitude, using a few arithmetic formulas in their hearts, they found the angle between the North Star and the ground, and then handed the results to Duhaiva.

After Du Haiwa inspected them one by one, she ridiculed the people who were not accurate, asked them to go out to retest, and praised those who calculated more accurately.

Speaking of arithmetic, it has become the knowledge that ordinary soldiers must master to become officers above the captain of fire, and there have always been military training courses on Snake Island, in which in addition to teaching officers to read and write, learn tactics and strategies, the main thing is to learn arithmetic.

Wang Junlin was overjoyed when he noticed that he was praised for his accurate calculations, and he was depressed when he miscalculated.

Wang Junlin was also happy to see that these people were so energetic in learning, knowing that this was the effect of the reward and punishment system that he had researched and formulated with Nie Xiaoyu before.

After the astrology, Du Haiwa took out a wooden disc with a big head from the cowhide backpack she carried, placed it on the wooden platform in front of her, and said: "This is called the latitude plate, which is the most difficult knowledge point in navigation. If you can learn the calculation method of dimensions, according to the regulations of our sailors, even if your ability in other aspects is worse, you will be given the equivalent treatment of the group leader. So far, only nine of the first batch of people trained by Lord Kraken have learned how to calculate latitude through dimensional disks. As long as you learn this method, you will be able to see the sea as a smooth road and never get lost. ”

During the three-day visit to Snake Island, Wang Junlin saw this thing in Nie Xiaoyu's hands, according to Nie Xiaoyu, the latitude disk she finally made was not like this, but unfortunately no one could learn it, so she studied such a latitude disk that can be fused with some contemporary Taoist knowledge.

"This latitudinal disk structure is divided into two parts, the celestial disk and the earth. The large and outer square plate is the territory, and the disk inside the territory is the heavenly disk. ”

Among them, the heavenly plate is used as a dipper, referring to Tiangang. The second is the twelfth chen, and the middle column is twenty-eight and four-dimensional bureaus. The land is listed in the four corners of the 12 Chen, the Eight Cadres, the Five Elements, the Thirty-six Birds, and the Heaven, the Gate, the Earth, the People, and the Ghost Road. ”

Du Haiwa was one of the nine who learned to operate the latitude disk, and while he introduced the fire chiefs and hundred leaders who looked at him with admiration, he used the previously measured data to compare the scales on the heavenly disk and the earth one by one to get the direction.