Chapter 42

How do you measure longitude? Hong Tao can both make and use a sextant. With this device, you can calculate the latitude and longitude of a ship by the angle of the sun, and the longitude by the angle of the moon and stars, and it is quite accurate, with a precision within five nautical miles. Even in the 21st century, many ships sailing the high seas still carry this ancient device. Why? Because modern equipment can have various problems, such as running out of power, human operational errors, or encountering solar flares. At such times, as long as you have a sextant, some knowledge of geometric calculations, and a table of lunar distances, your ship will at least not deviate too much from its course. This is also why obtaining a Class A sailing license requires learning so much ancient navigation knowledge and is a mandatory exam. Sailing long distances is very dangerous, and knowing more skills means having more chances of survival!

However, Hong Tao currently cannot make a sextant. He can find all the raw materials, except for one thing: mirrors! A sextant requires two small mirrors and two lenses, so to make a sextant, he first needs to be able to make mirrors.

Actually, mirrors are not absolutely necessary. Using a piece of crystal with a silver backing can also work, but unfortunately, Hong Tao can't even get crystal right now. However, he is not in a hurry to go sailing. The purpose of sailing is to open new routes, and the purpose of opening new routes is to draw long-distance trade maps and train sailors, and the purpose of long-distance trade is to make money. He hasn't even figured out what the cities of the Song Dynasty look like, and he doesn't have a suitable ship for long-distance voyages. Why rush to make a sextant? Even if he were given a global GPS system now, he wouldn't dare to sail a long distance with Bo Xiaoer's small wooden boat, let alone Luo Youfu's green-browed bird ship. They are too slow and have poor resistance to wind and waves. The only advantage is that they can carry more cargo.

Hong Tao's mindset is completely different from that of people in this era. He doesn't seek to carry too much cargo; he only cares about seaworthiness and speed. The profit in long-distance navigation lies in the distance, not the amount of cargo. Of course, if he could have a large sailing ship that carries a lot of cargo, is seaworthy, and has a high speed, like the clipper ships that appeared in the 19th century, Hong Tao would be even happier. But he can't make that kind of ship right now. He has a lot of navigation knowledge, but he is only half-competent in how to build wooden sailing ships and is not yet capable of designing and supervising the construction of large ships. At most, he can give the shipbuilders a few ideas.

"Uncle Cai, what do you think of Hong Tao?" The Song people go to bed very early, and the Tanka people lie down by 8:00 PM every day. Hong Tao didn't want to keep Luo Youde up, so he didn't ask if he was tired. He didn't want to annoy him, so he decided to go to bed himself. When a servant led Hong Tao out of the second-floor living room of the stern cabin, Luo Youde stood by the window, watching Hong Tao, who had already entered the bow cabin, and softly asked his assistant, Uncle Cai.

"It's hard to say. I've never seen anyone like him. His background is too bizarre. I've been to the South Seas for fifteen years, visiting all kinds of countries and islands, but I've never heard of a place called Australia! His speech, habits, and attire are completely different from anyone I've met, and it's not something he can fake. It's truly bizarre, truly bizarre!" At this moment, the butler named Uncle Cai changed his usual respectful demeanor, sitting down in a chair and speaking in a different tone.

"He says he can make glass, and I see he is proficient in navigation. He not only understands sea charts but also spoke meaningfully when talking to Luo Tian. Perhaps keeping him in our fleet could turn our fortunes around." Luo Youde continued to stand by the window, looking at the dark sea outside, lost in thought.

"Judging from his attitude, it will be difficult... This young man is casual, but he has depth. He doesn't seem like someone who would be content to be subordinate. He is merely curious about all the furnishings and tools here, showing no envy at all, and he has no interest in our courtesans, not even a glance. I've never seen such a young man with such an attitude. It's hard to fathom! You've been through a lot since your father passed away, but there's no need to rush. I think it's better to observe him more." Uncle Cai recounted his observations of Hong Tao and gave a less enthusiastic suggestion.

"Alright, let's observe him more. After we reach Zhenzhou, I'll talk to him more and spend a few days to understand his background. Oh, glass, glass... He said he can make glass, and that glass is as cheap as porcelain in his hometown. Why haven't we seen a single merchant ship from Australia in all these years?" Luo Youde accepted Uncle Cai's suggestion but was still muttering to himself, clearly not letting go of the idea.

Zhenzhou, a small port in Luo Youde's words, left Hong Tao spellbound. Even when the ship was still a few nautical miles from the port, the sea was already different, with ships of all sizes coming and going, just as many as in the modern Sanya Port. The ships were clearly smaller in tonnage, mostly wooden boats with a displacement of a few dozen tons, like the Tanka boats, scattered in the sea near the port. There were also larger ships, some even bigger than Luo Youde's, with different appearances. Some ships even had five masts, with sails in three layers, like flowers blooming at sea, but they didn't help much with speed.

"These large ships are on their way to Guangzhou and Quanzhou, and they will continue north to Jiangyin, Xiuzhou Huating, Xiuzhou Ganshu, Hangzhou, Mingzhou, and Wenzhou. Some will continue east to Goryeo and Japan." Luo Youde stood next to Hong Tao, not focusing on the ships at sea but observing Hong Tao's reaction out of the corner of his eye.

"Are there maritime trade offices in all these eight ports?" Hong Tao was very surprised. The Song Dynasty was incredibly open, with almost all the seas open and all of them being foreign trade ports.

"There are also Zhenzhou and Qiongzhou, but these two places are military towns built by themselves, mainly to exchange rice from the South Seas. Relying on land transport to bring rice here is too costly and time-consuming, so it's better for merchants to bring rice back from the South Seas on their way." Luo Youde was happy to explain these Song Dynasty regulations to Hong Tao, not just explaining but also interpreting them.

"What if the merchants don't want to transport rice? I think transporting rice is definitely less profitable than transporting spices." Hong Tao was also willing to discuss these issues with Luo Youde. The Song Dynasty was still very mysterious to him, completely different from what he had imagined, and it was necessary to understand it carefully.