Da Vinci finally made the sextant, and its efficiency is much happier than the last time he made a wind-up gun. It's no wonder that Da Vinci was a little perfunctory last time, but this time he worked hard for his little lover.
Therefore, in a short period of time, Da Vinci successfully developed the sextant that Marin said. Not only that, Da Vinci also compiled a set of calculation tables and look-up tables. When measuring latitude, you only need to measure the angle between the sun and the sea level, and you can directly get the latitude data according to the look-up table. Of course, if the angle is not an integer, it can be calculated according to the formula. It should be noted that this lookup table is related to the season and the height of the sun. Such things were naturally done by Marin and Da Vinci together. Because Da Vinci's concept of the height of the sun is still very vague, and Marin, who has never studied geography in middle school, is sure. Therefore, the calendar comparison table in the lookup table is mostly made by Marin.
In this way, as long as the captain is good at mathematics, he can easily calculate the latitude according to the comparison table. As for longitude, it's a little trickier. Although Leonardo da Vinci and Italian watchmakers developed clockwork clocks with good precision, the accuracy is still a bit problematic. Therefore, Marin asked them to test repeatedly to test the error of the clockwork. Every day at noon, the time is compared once to record the error. Then, when sailing, you can judge the exact time based on the average error.
The reason why the error is recorded every day is actually to select the nautical clock with the most stable error. The error is stable, indicating that this clock is the most accurate. As long as a fixed error is added or subtracted at noon every day, the time can be easily adjusted. And if the error is unstable, the error is 10 minutes today, and the error is 20 minutes tomorrow. Such a kind cannot be used to calculate time.
When at sea, the captain can arrange for someone to adjust the error once a day to maintain the accuracy of the time. Then, based on the time difference, the longitude can be easily calculated.
As for how to calculate longitude? This is easier. As long as the time of the nautical clock is accurate, during the voyage, when the sun is in the middle position at noon, the current position and the standard of Aurich time can be easily judged based on the accurate time obtained from the average error of multiple nautical clocks jet lag.
The circumference of the earth is 40,000 kilometers, and it is divided into 24 time zones. That is, each time zone is 1666.667 kilometers long. The difference between the current position and Aurich is a few hours, that is, a few 1666.667 kilometers away. Marin did not tell Amerigo the circumference of the earth, but he told him that the difference in lateral distance was 1666.67 kilometers in one hour. Then, just calculate according to this principle. As for more, he didn't tell Amerigo either. After all, he didn't intend to let him sail around the world, so why do he know so much
After selecting the 10 clockwork nautical clocks with the most stable errors, Marin called Amerigo over and asked Da Vinci to teach him the usage of sextant and the algorithm of latitude. Marin, on the other hand, told him the algorithm of the lateral distance.
In fact, because Magellan has not yet sailed around the world, the concept of latitude is not very clear to everyone. But Amerigo was a good captain and a half-astronomer. Therefore, it is not difficult to teach him.
Anyway, Marin only asked him to use a sextant to calculate the latitude and lateral distance of each node on the route. Then, record it in the logbook.
At that time, based on the horizontal distance, Marin can easily calculate the longitude. With longitude and latitude data, plus the use of a sextant. As long as the next captain knows how to calculate longitude and lateral distance, he can easily correct the course and reach the destination.
After Marin and Da Vinci taught Amerigo how to use the sextant and how to calculate the lateral distance (longitude), within a few days, good news came from Te Horenche—two 250-level armed ships Merchant ships are also ready. These two ships, by convention, were named 2503 and 2504 respectively…
The reason why it was built so quickly is really because of sufficient experience before. In addition, Marin is very good at supplying materials, and there is no such thing as halfway waiting for materials. In addition, the craftsmen are also familiar with it, so it is naturally easy to make.
It's just that when manufacturing 250-class armed merchant ships, Marin actually kept his hand and did not hand over the technology of high-temperature steam processing ship ribs to the Te Horenche Shipyard. Therefore, when the Te Horenche Shipyard manufactures ship ribs, it still uses the old method of sawing a very wide piece of wood into an arc, which is a waste of wood. At this point, the cost of making the ship's ribs at Te Horencher Shipyard is still very high.
However, Marin also thought of a good way, which is to ask Emden Shipyard to send the processed ship ribs to Te Horencher. In this way, there is no need for the Te Horenche Shipyard to waste so much wood. As long as they inform Emden Shipyard of the specifications and sizes of the ship's ribs, the craftsmen of Emden Shipyard can use steam boxes to process the corresponding ship's rib pattern requirements, and then ship them to Te Horenche.
Generally, there are not many ship ribs used on merchant ships. A ship with a keel length of 24 meters only needs 33 pairs of ship ribs. Class 250 armed merchant ships, because the keel length is only 20 meters, only 27 pairs of ship ribs are enough. After using the high-temperature steam box to process, the cost of the ship's ribs is much lower, it is not complicated, and there is no waste of wood. As long as the processed ship ribs are air-dried again, they can be taken back and nailed to the keel. After the skeleton is finished, the outside can be covered with planks. Then, it's time to paint and paint...
In fact, the materials for the two ships 2503 and 2504 were prepared early in the morning. Therefore, this shipbuilding saves a lot of material preparation time. Therefore, the Te Horencher Shipyard was able to build and launch both ships in just four months. Because, the ship's rib, which is the most difficult to process in a ship, was actually processed together when 2501 and 2502 were manufactured last time. Therefore, this shipbuilding was very fast.
The 500-ton warship that Marin asked Emden Shipyard to manufacture was not so fast. Among them, bending the ship's ribs with a high-temperature steam box saves money but takes time. Not the processing time, but the drying time after processing...
Shipbuilding wood cannot be damp. Therefore, the wood used for shipbuilding is all wood that has been air-dried for one or two years. Earmarin let the craftsmen smoke the ribs of the boat for several hours with high-temperature steam, and the previous drying efforts were all in vain. Therefore, after the ship's ribs are processed and formed, they have to be air-dried again for several months.
In other words, if you want to wait until the ribs of this boat are nailed to the keel, you will have to wait for several months. No wonder ancient shipbuilding took a year at every turn...
Marin thought about it, it was too time-consuming. So, he simply ordered a large amount of wood again, and asked the craftsmen of Emden Shipyard to process an extra batch of spare ship ribs. This way, the ribs will not have to be fumigated and processed again when the next boat is built. After all, the newly processed ship ribs have to be air-dried for several months, which is a waste of time. If the processing time of the ship's ribs is excluded, and the keel and planks are ready, a ship can be built in three to four months.
Thinking of this, Marin's heart was very hot. It seems that there is still a bright future for logging in the Americas. If a large amount of wood is prepared in the Americas, it will be processed intensively into useful keels and ship ribs. In the case of complete materials, as long as there are enough craftsmen, the ship can be exploded like a soldier...
Therefore, when Amerigo adjusted the crew and prepared all the supplies, Malinte grabbed him and asked him to modify the route...
Seeing that Marin took out a map with the outline of the east coast of North America, Amerigo was a little confused:
"My lord, this is?"
"This is the coastline map of the east coast of the wild continent..."
"This... is this true? Someone has explored the wild continent before?" Amerigo was taken aback. You know, now Europeans only know some islands in the Caribbean that Columbus explored...
"My teacher Einstein Daxian once visited these places..."
"My lord, your request is..."
"After you explore Grenada, go north along the Windward Islands. When you reach Barbuda, turn northwest and go to the Bahamas first discovered by Columbus... Remember, don't continue north on Barbuda, there is The Bermuda Devil's Triangle…”
"Bermuda... Devil's Triangle..." Amerigo trembled, a little frightened.
"Well, this huge sea area is very dangerous. My teacher said that there are devils under the sea, which will swallow ships. He even heard the howling of devils... Moreover, the seaweed in this sea is big and long, and it is easy to Entangle the boat. My teacher said that those seaweeds may be driven by demons, and they dragged the boat and people into Haiti..." Marin said mysteriously.
Amerigo was a little spooked, though, he didn't really believe in devils. But the huge seaweed made him a little intimidated. Because, if the seaweed is long enough, it can indeed entangle the boat. In inland river areas, it is normal for boats to become entangled in algae. But it's nothing if the boat gets entangled in inland algae. Because people can abandon the ship and go ashore for help.
However, in the middle of the vast sea, if the boat is entangled in seaweed, it will really be "not working every day, and the earth should not work". Therefore, Amerigo nodded fiercely, expressing that he would not commit suicide.
Then, Marin continued to point out:
"After you arrive in the Bahamas, sail northwest, and you will encounter real land. This is the Florida peninsula of the wild continent. You will go north along the peninsula, at about 40 degrees 43 minutes north latitude, and you will arrive in New York—ah bah, New York is still there It didn't appear..." Marin remembered that none of the place names he marked appeared...
But it doesn't matter, he continues to talk...
"After you arrive in New York, continue to sail northeast along the coast. Then, you will see two small islands... The one near the land is called Martha's Vineyard, and the other is called Nantucket... The second mission this time , is to discover these two islands…”
"Lord Earl, why don't you send troops to occupy such a large piece of land? Why do you only need two small islands?" Amerigo asked puzzled.
"Amerigo, you don't understand. Although the land is large, it is full of dense jungles. There are many fierce Indians in the jungle. If I let you go ashore rashly, you will be easily shot to death by Indian bows and arrows. Therefore, I asked you to find these two small islands first, in order to gain a foothold first, and then use this as a springboard and base to attack the mainland... "
This is Marin's strategy. Marin thought for a long time, and felt that he was currently weak and had a small population, so he could not immediately colonize on a large scale.
Moreover, the premise of colonizing America is that what is most needed is not land, but a foothold. Just like when the British colonized North America later, they rashly landed directly on the land of Virginia. As a result, they fought many times with the Indians. When they were besieged, when the colonists in the British colonies had no food, they were so miserable that they could eat people. the point.
Therefore, Marin will not make that mistake. The Martha's Vineyard and Nantucket islands he chose are both small islands of two to three hundred square kilometers, isolated overseas. There are few, if any, Indians on the island.
On these two islands, Marin can easily occupy and develop with peace of mind. For example, logging, building farms and ranches...
In short, developing on two small sea islands will not offend the Indian tribes on the main road. Even if they are dissatisfied, they are unable to attack the island. Because the Indians are still in the era of using canoes. Marin can knock down all the Indians' canoes if he goes out with any boat...
Moreover, these two islands were also carefully selected by Marin. First of all, Martha's Vineyard and Nantucket Island are both about two hundred and tens of square kilometers in area, and Bissel Island is much larger. Such a large island can completely open up a lot of farmland.
With farmland, there is enough food to supply the needs of the colonists. In this way, the colonial activities can be carried out smoothly. Moreover, the two islands are very safe and do not worry about Indian attacks.
Not only that, but Nantucket Island was later a famous whaling center in the United States. It is not far from the Newfoundland Fishing Ground, one of the four largest fishing grounds in the world, and is rich in fishery resources. Therefore, many whales often appear in this generation's sea area.
As long as Marin sends a few whaling ships here, he can catch many, many whales. You must know that the whaling industry has not yet emerged these days, and there are plenty of whales in the sea. As long as whales are caught, not only can a lot of whale meat be obtained, but tons of whale oil can also be obtained.
Whale meat can be made into dried salted fish, which can definitely satisfy your hunger. A whale, the lightest one weighs more than two tons, can obtain nearly one ton of whale meat. A ton of whale meat can feed several people for a year. Don't talk about those larger whales, which weigh dozens of tons at every turn. As long as a whale is captured, it can provide a large amount of meat.
And, whale oil is also important. In this era of lack of vegetable oil, the common people can also eat some whale oil. Although, whale oil doesn't taste good. But for the poor, it is good to have oil and water, how dare you be picky
Not only that, whale oil can be used to light oil lamps, provide lighting, and can also be processed into candles. The top grade of candles for candlelight dinners in later generations is processed from whale oil.
Moreover, the cost of using whale oil to make soap is also very low. In short, the whaling industry, it is very beneficial...
These two small islands can be used not only for farming, but also for raising livestock, and can also be used as a base for whaling and catching common fish... In short, it is a perfect food supply base...
When Marin's men have a firm foothold on these two islands, they can use this as their base camp to march to land and occupy new colonies. The new colony was first built by the sea, so that it would not be afraid of being besieged by the Indians. Even if the Indians surround the new colony on land, the two small islands can provide enough supplies for the colony through warships, so as not to run out of food like a stupid British guy and get to the point where people cannibalize...
Before Amerigo boarded the ship, Marin took his hand and said:
"Work hard, Amerigo, when you come back this time, if you successfully discover these two places, I will confer you a hereditary knighthood and reward you with 10,000 gold coins... You know, the meaning of discovering wild islands and discovering India It’s different, so I conferred the title of Baron Columbus all at once, you should understand, right?”
Amerigo nodded, of course he knew the significance of Columbus's discovery of India. After all, the discovery of India brought Marin huge profits of millions of gold coins, and it was normal for Columbus to be named a baron. And this time, exploring the islands of the Wild Continent by himself will not bring any huge profits. Therefore, it is kind of Marin to confer himself a hereditary knight. After all, it is hereditary.
Before breaking up, Marin asked Amerigo to write a family letter, the purpose of which was to bring all Amerigo's family members to Aurich. Amerigo also understood that this was Marin asking for a hostage. Because Marin was worried that Amerigo would disclose his information to others. However, this was also a common practice in ancient times, and it was commonly used by nobles, and Amerigo didn't have much resistance.
In this way, under Marin's expectant eyes, Amerigo took the selected players, boarded two 250-level armed merchant ships, and two smaller warships captured from the original Friesland, and set foot on the In order to explore the journey of Grenada and the twin islands of North America...