Geographic maps

In the 15th century, the needs of the nobility in luxury are increasing. The demand for gold, spices and spices is great. All this is in the "Indians", as the countries of Southeast Asia were then called. For the development of navigation, we needed geographic maps. From the Arabs Europeans received materials of ancient geographers found in the destroyed cities and libraries of the former Roman Empire. Numerous tables of geographical coordinates are being known for many points of the already open world. Basics for these tables, the Arabs borrowed from the works of the outstanding scholar of antiquity Claudius Ptolemy. The Italians make a map of the new materials of travelers. The Catalan geographical map of the world (1375), the geographical maps of the Venetian cartographer Andrew Bianchi (1436), and the beautiful geographical maps of Fra Mauro (1459) were widely known at that time.

For the development of navigation, we needed geographic maps

On the geographical maps of Fra Mauro, all the inhabited land is "squeezed" into one hemisphere. In the west, the contours of the coasts of Spain, Portugal, France (Gaul), Italy and other Mediterranean countries are very clearly and with great certainty. Showing the west coast of Africa, the south of which is compressed by the frame of the map. The Persian Gulf, the Red Sea, the Indian Sea and three "India" are clearly shown. The first is "India prima," the second is "Bengal India the second", the third is "India's Chinese", or "Tertz". The island of Ceylon (Zailam), Sumatra island, or Taproban, in the East of Java island and "Java major" and, finally, Simpango, or Chipanga - Japan are shown. There are no American continents on these maps. The second, implied hemisphere is occupied by the Sea-Ocean, or by the Sea of Darkness, where the path is considered "God-forgiving", almost forbidden.

Geographic maps of Ptolemy, whose authority of works was then unshakable, showed that half of the habitable and known land was then consumed. But the already recognized the sphericity of the Earth, the need, what at any rate, to get to the "India", where the goods needed in Europe, and many unsuccessful attempts to overtake Africa are increasingly evoking the idea of a journey to the west...

Creation of geographical maps is carried out with the help of cartographic projections - the way of transition from a real, geometrically complex earth surface to the plane of the map. To do this, first go to the mathematically correct figure of the ellipsoid or bullet, and then project the image onto the plane using mathematical dependencies. Various auxiliary surfaces are used: a cylinder, a cone, a plane. In this case, almost the standard now is the location of the sides of the world: the north on top and respectively the south at the bottom, the west on the left and the east on the right, relative to the viewer.

Any geographical maps contain distortions of lengths, angles, shapes and areas. These distortions are of different types, and their magnitude depends on the type of projection, the scale of the map and the coverage of the projected territory. It is possible to find length distortions along the meridians on the map by comparing the lengths of meridians between two adjacent parallels - if they are on the same level, then there is no distortion of length. A distortion of angles characteristic of most maps can be inferred when parallels and meridians do not form right angles with each other. To distinguish the distortions of the form, you can compare the length and width of any geographical object on the geographic map and the globe - if the proportions of the forms are proportional, then there is no distortion according to this criterion.