Maps and sailing
This text is connected to an image, that portraits the ancient map. That map is so inaccurate, that we cannot even believe, that somebody can navigate with that thing. The inaccuracy of the ancient maps is understandable because at that time were not GPS systems and satellites, and people thought that the Earth was flat, which caused the problems with cartography.
The thing is that if the form of the Earth is wrong, the projection of the map goes wrong, and that thing causes inaccuracy in the maps. So that is one example, how necessary is to know the form of the Earth or every other particle if we want to make the map for that thing. But those ancient maps were used for navigation.
How to use this kind of map in navigation?
The answer is that the ancient sailors followed the coastline, and that means that those sailors didn't need the maps at all. They needed the list of the cities, what they should pass, and the rules, how to sail between those cities. Things like reefs can pass by taking enough distance from the coastline. Or they can be found by measuring the depth by using the rope, where is a stone or some other weight.
In the time of trimarans, the depth of the ships was not very big, and that means that the sailors didn't need so big skills. So the ships, what were row stayed near the coastline, rather than went to open seas. The great sailships went to the open sea because of their depth was too big for the coastal sailing. The thing is that until the radio was invented the leaving from the coastline was dangerous because the ship would not find back to the port.
The reason why the western seafaring advanced in the Mediterranean area is that the sea area is limited. And there are many islands. Of course, Polynesians created also very effective ways to sail, and the skills of those Polynesian sailors are impressive. But the reason, why the Polynesians are good sailors is similar to the Mediterranean people. Compass made possible to determine the direction, where the ship was going. And the mechanical clock, the chronometer was necessary to determine the longitude. The sextant was used to determine the latitude.
Radio navigation.
Modern sailors use radio navigation systems and GPS for finding their locations. The radio navigation system called "Loran" is one of the most brilliant inventions, which is created for ships. The "Loran" system is the radio transmitter, which sends the signal, and the ship, what uses the radio bearing system must just drive towards the radio, what just repeats the name of the harbor, and that is one of the simplest and effective ways to navigate without satellites.
And the Loran is more effective than satellite if we must find the direction, where we want to drive our ship. If we are at open seas, we must take the bearing, and lock the inertial in that direction. That thing is a very suitable navigation system in the middle of the Atlantic, but at the archipelago, we must use a more advanced navigation system in use.
Image:
https://allthatsinteresting.com/wordpress/wp-content/uploads/2017/05/posidonius-early-world-maps.jpg
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