The ship is the foundation, and with the ship, it is just a foundation, representing the possibility of crossing the ocean, so that in the deep sea, in the face of a conventional, or a slight wave of wind and waves, it sinks, and there is no way to cross the ocean.

But a good ship is only the foundation, with this foundation, does not mean that it can cross the ocean, if there is no way to measure the distance, then the sea is a nightmare for them.

The terrible sea is like this, even if the ship has the means to conquer the sea, without a range, it cannot conquer the sea, the sea is vast, larger than the land area, the so-called sea channels are also on the sea chart, really in the sea, a vast expanse, if you lose your way and keep going around in circles, then even if the ship does not sink and loses its bearing, it can only go with the current.

In this case, there are only two results, one is lucky, sent to land by the sea breeze, and escapes, or it is the result of death, this death, perhaps in the drifting sea, finally encountered an irresistible wind and waves, completely sank into the sea, or, after sepsis and all kinds of supplies were exhausted, in the end, the whole ship died, unable to control the ship, and turned the ship into a ghost ship.

Surveying, has always been the most important element of navigation, in the early seagoing ships, there has always been a position of navigator, this navigator, on the one hand, if you are familiar with the route, is very familiar with the route, on the other hand, also knows how to measure and calculate, so that you can guide the direction on the sea.

Perhaps, when the storm comes, in the face of stormy seas, or when pirates attack, it is the captain who gives the order, but when the navigator finds the right channel after the regular voyage, or even after the loss, the navigator is the leader, and only under the guidance of the navigator can he reach the destination faster and safer.

In the early days of seafaring, there was only one compass, not even a compass, and they faced the ocean as if dancing with death, a route, a secret supply point, would give them a trade route full of gold, but even so, the endless sea, buried countless people.

Experience and calculation, this in the absence of a sextant, the huge error of the range, will make navigation a very dangerous thing, even how experienced the captain, before getting on the ship, is also full of unknowns, the general will inevitably die in battle, for the captain, if he can't make a lot of money, timely exit the voyage, then waiting for him, is not known which day can not return.

In the early and even middle days of the Age of Sail, countless people made a lot of money through sailing, but there were also countless people who threw themselves into the ocean and died at the bottom of the sea forever.

This is the fate of the seafarers, and this is the tradition of the seafarers, who are not confined to one city or one place, and in the Age of Discovery, they may be in Europe this year and Asia next year, and the Americas in another year.

When you are lucky, you can make money, often in the port, when you have money, it is the uncle, call friends, spend the night in the life of the groom, when you have no money, you climb the ship, in the wind and waves, and danger, to earn money.

Zhao Xin knows very well that this is the Age of Sail, and even some of the captains and seafarers pushed out, how many of them are true, it's really hard to say, maybe it's the power class, for the sake of interests, keep promoting, it is countless seafarers, one after another, and finally let Europe get the great geographical discovery, this after the Renaissance, only to overtake the Caucasian, began to establish a leading position, completely beyond the East.

Countless people were stimulated with interests, one after another into the ocean, relying on the terrible profits of sea trade, to promote the development of shipbuilding and shipbuilding technology, at the beginning of the Age of Sail, only very poor ships in Europe, gradually matured, laid the pinnacle of the sail fleet.

In 1840, during the Opium War, neither Britain nor France sent the most elite fleet to Asia, but even so, the British army's three battleships with 74 main guns also made Zhonggou feel shocked, a ship, with the vitality of a fleet, more than a dozen fleets, completely suppressed the army's batteries, the strong veil of the Qing Dynasty, was completely torn off, an era ended, and China entered a semi-feudal and semi-colonial era.

If you are backward, you will inevitably be beaten, and this is the lesson learned in the tragic history of modern times, and it is even said that the Northern Song Dynasty also has a history of extinction twice.

Even Europe, which has a population of less than a few people, can use this method to overtake in a corner, and now, with 100 million, and in the future, after perfecting grain cultivation and obtaining high-yield crops, the population will further grow in the Northern Song Dynasty, it is impossible not to have such confidence.

China's maritime merchants have been going to sea since a long time ago, and the trade with Southeast Asia can even be traced back to the Han and Tang dynasties, but for China, maritime merchants are not cost-effective.

Simply shipping some Chinese specialties, such as tea, silk and porcelain, to overseas for sale can be a huge benefit, but this benefit is one-way, because there is nothing worth getting overseas.

For example, in the Yuan and Ming dynasties, the trade with Japan, the transportation of things in the past, can obtain huge benefits, but the transportation back, Japanese swords, fans, or some handicrafts, this thing can really only be regarded as unsatisfactory.

In the same way, the same is true in other places, if you can't get huge benefits back and forth, you will have poor ability to bear it, and once there is a huge disaster, everything will cease to exist.

Overseas barren, of course, barren, this barren refers to the degree of development, compared with the Chinese civilization with a history of 5,000 years of civilization, but also the development of Southeast Asia and various island countries, relatively lagging behind, for example, Southeast Asia in this era, except for some weak countries, is a large area of primeval forest.

But of course Zhao Xin knew that these places contained countless treasures, but because they had not been developed, they were buried underground, for example, in Japan's Iwami Silver Mountain, at its peak, it supplied one-third of the world's silver production, which lasted for hundreds of years.

Any thing, to the height of world production, is an extremely terrible output, let alone a period of hundreds of years, not to mention the iron ore in the Korean Peninsula, Southeast Asia, copper and various precious metals in the Indochina Peninsula, which can support the development of the entire Ding Navy.

The reason why industrialization is industrialization is the ability to devour raw materials in large quantities and turn them into industrial products.

China's lack of precious metals, whether it is silver, gold, or bronze, is not China's large output, which is also the fundamental reason why China has not developed into a three-tier precious metal monetary system.

Once the Chinese understand that overseas is not a barren and barren land, and is full of various interests, the Chinese who dare to work hard will naturally go to the ocean, and there will be a steady stream of people bringing overseas and many resources back to China.

It is not impossible to pave a path to the great geographical discovery with death and succession, China has enough personnel to support this plan, and even the resources invested are dozens of times higher than that of Europe, but this is not the most suitable choice.

The road paved with human life is that there is no choice, there is no way to use effective and faster methods, under the premise of finding the right chart, only one person, inch by inch, can fill in a road to the ocean, and gradually improve the nautical charts in the succession, these nautical charts, at some times, are the highest secret of a country, on the warships of the Age of Sail, once they encounter pirates or other attacks, when there is no chance of survival, the captain or navigator, The first thing to do is to destroy the charts.

For Zhao Xin, he already has a basic map image, for example, Asia, Europe, Africa, North and South America, Oceania, maybe there is no precise coordinate location, but the general direction and layout are there, just this point, can be compared with the historical era of navigation, I don't know how much better.

In order to perfect the seven seas, the five continents, the four oceans, Europe has gone through hundreds of years of history, the earth is round, as early as the fifth century B.C., it was proposed, there have been many arguments about this, but when Magellan crossed the entire earth, it was finally proved.

This voyage that went down in history lasted 3 years, and even Magellan himself died in the Philippines, but his significance is very huge, he proved the hypothesis that the global ocean is truly connected as a whole, in the ocean, in any direction, can reach the final destination, which makes the design of many routes, much more flexible, but also makes some important straits, become a place of contention for the ocean.

After having the basic continental morphology of the earth, adding the theory of the sextant, even if it can't be made into an accurate sextant, a simple sextant with an error control to the visual range is enough to make the navigation of the Northern Song Dynasty more stable.

The sextant is an optical instrument, what needs to be measured is a few data, these data are basically the angle of the sun, at different times, at different times of the sun angle, the angle of the sun in multiple regions is in line with the calculation, which requires very advanced knowledge, at present, Zhao Xin is half-understood, he doesn't even know that those data are useful.

At the same time, one of the most important problems is that very few people in the entire Dinghai Navy, and even in the Northern Song Dynasty, understand astrophysics and even some basic theories of optics.

can only get all the data out, and then according to the original earth, the division of latitude and longitude, and then substitute them one by one, and then train a group of people who know how to manipulate the sextant.

This substitution process is very slow, the method determined by Polaris is only one of the many methods provided by Zhao Xin, and even he doesn't know which method is the most correct, so it is necessary to use various methods to verify this.

This verification point is the coordinates of some important positions that have been determined, which becomes the key point to verify whether this formula is correct or not.

Zhao Xin is not a navigator, nor is he a researcher of the ocean, what he can rely on is the majors in the university and some knowledge points up to high school, but it is these knowledge points that give a clear coordinate.

For example, in geographical knowledge, the southernmost point above Chinese mainland, the Leizhou Peninsula, his dimension is 16 degrees, and there is one of the most important lines, the Tropic of Cancer, the northernmost point of the direct sun, he will be at a certain limit of time, the noon sun is overhead, that is, like a column, there will be no shadow, is a point.

The equator and the Tropic of Cancer are the most important positions above the dimensional line, and to a certain extent, what Zhao Xin can know is also the Tropic of Cancer.

Among the geography knowledge in high school, the Tropic of Cancer has several important cities in China, a little north of Guangzhou, Shantou City, and Chiayi in Taiwan.

Among them, Chiayi doesn't mention it for the time being, where is it still a wild land, still in the hands of the Gaoshan clan, there are primeval forests everywhere, but in other places, it is easy to do.

Guangzhou, even in the Western Han Dynasty, has been opened up into a city during the Three Kingdoms period, and the unique conditions of this city, especially the advantages of the sea, make them relatively large, but a little far away.

As for Shantou, it is much worse, now it is just a village, in fact, before the Yuan Dynasty, the only important ports on the entire Chinese territory were Guangzhou and Quanzhou, and the others were either just a fishing port or did not enter the stream.

Whether it is the Tropic of Cancer or the 16-dimensional line of the Leizhou Peninsula, these are some basic things, and these data can help Zhao Xin determine the latitude and longitude lines faster.

Zhao Xin is also very helpless, in addition to these, in addition, in the geography textbook, the coordinates have little effect on him, for example, in the geography textbook, the southeast and northwest, the four poles.

They all match the coordinates of latitude and longitude, the easternmost Heilongjiang River, the southernmost Zengmu Dark Sand in China, the Mohe River in the north, and the Pamir Plateau in the west, these are the problems of China's extreme territory, even if you know the exact place, you can't go, and Zhao Xin can't go to these places for the time being.

Because it is absolutely a barren land, Mohe and Heilongjiang, in the northernmost part of China, there are now the territory of the Jurchens and some nomads who do not bloom, and it is impossible to penetrate deeply.

The Pamirs are similar to the Great-Mother Sands, both of which are off-the-beaten-path and not well-known in this era.

He still knows the distance of each degree of latitude and longitude, as long as the latitude and longitude of a certain point is determined at a certain point, he can mark the latitude and longitude of the entire important port of the Northern Song Dynasty step by step through all kinds of the same things, and the more locations and data for ranging, the easier it is to get.

These fixed points, as a verification, and then summarize the rest of the entire grid line, once China is the core, the entire Northern Song Dynasty's latitude and longitude map is completed, the role of the sextant, will be highlighted.