Cartography

History

At the time modern, the charts want to be a faithful reproduction of a landscape, of a portion of terrestrial space: all the components of a landscape are represented according to conventions, with symbols. Each element is represented on the scale of reality; the too small elements in plane surface are replaced by symbols of a size proportional to their relative importance (increasingly large names of the cities according to their population or their administrative office).

That was not always the case. At the 9th century, the Église represents the cosmogonic world of way: the charts in T. Jerusalem is in the center, only exist the Europe, the Africa and the Asia, surrounded by an ocean. These representations are directly inspired of knowledge of the biblical Period. This type of charts was not used to be located. They were a support with the philosophical reflection and nun the first cartographic representations are born at the 12th century. The Table of Peutinger is used then as route between several cities and/or areas, in a linear way.

Towards the end of the 13th century, a new type of chart appeared: the Portulan, very useful for the sailors. It represented the commercial ports, the Amer S (fixed and visible objects being useful of benchmark at sea or on the coast), the islands and the shelters, etc; but the interior of the coasts remained virgin.

In 1553, the first chart of France is drawn up by Oronce Fine (available on the site of the National library of France). She testifies to the will of the political power to mark her presence on the territory, to affirm, to build limits, borders, to arrange her territory, inter alia by the taxation and the consolidation of the internal economic markets. At the same time appear the foregrounds burrows, ancestor of the current land register.

At the 16th century with Dieppe an important school of cartography appears. Carried out by Pierre Desceliers, this one allows the realization of many charts and maps of the world, based at the same time on the portulans of the Portuguese sailors and the last knowledge acquired by the exploration of the Canada in which the Dieppois sailors took an active part.

Then the cartography will progress more and more, by the development of novel methods and by the will of the political powers to control their territories, the support testifies some which the cartographic missions of the very powerful geographical companies of the end of the XIXe century received.

Two decisive stages were the development of the techniques of determination of the Longitude and the Latitude.

France

In France, the first general chart of the territory was drawn up by the family Cassini at the 18th century, on a line scale percent measuring apparatuses, in other words a scale of 1/86 400. One centimetre on the chart corresponds to approximately 864 meters on the ground.

This chart constituted for the time a true innovation and a decisive technical projection. It is the first chart to be based on a geodetic triangulation whose establishment took more than fifty years. The four generations of Cassini followed one another to complete this work. This chart, still called Chart of Cassini or chart of the Academy , is always consulted nowadays by researchers (geographers, historians, genealogists, etc). The work of Cassini left even its print on the ground: one finds still today toponyms known as Signal of Cassini , which reveal the places where measurements of the time were carried out. These benchmarks correspond to the tops of some thousand triangles which formed the geodetic network of the chart of Cassini.

In 1808, Napoleon I {{er}} decided the establishment of a chart intended to replace that of Cassini; its implementation will be done between 1817 and 1866 by testing several different scales. It is a chart with the use of the soldiers: the Geological Survey map , on a 1/80 scale; 000. This from now on celebrates Geological Survey map was raised and drawn by the Dépôt of the War , become then the Service geographical of the army, and replaced later by the national geographical Institut (IGN).

Charts with the 1/80 000 generally appeared as a mosaic of paper squares stuck on a fabric, itself folded and protected by a hard-bound and cloth-lined cover very hard; it could thus answer the constraints of ground of the soldiers and the gendarmes.

To the beginning of the First World War (1914-1918), the difficulties of reading on this scale led the staff to carry out a chart with the 1/50 000, more convenient, on which appears a very practical kilometric squaring on the ground.

It is on the basis of this chart to the 1/50 000 that will be created the chart with the 1/25 000 of the IGN, called today chart of excursion but that the French called a long time, by practice, Geological Survey map .

Plagiarism

Since the cartography is a difficult work and sometimes even dangerous, it is not astonishing whereas many cartographers copied the work of other cartographers.

At the 17th century it was normal to use the work of the others and to add it to his; it was not perceived as vol. One of the first charts of North America is known under the name of Beaver Map (Chart of the beaver). It was published in 1715 by Hermann Moll, but Nicolas de Fer is the true author of Beaver Map although it is Hermann Moll who benefitted from it. In turn, its chart included/understood images of the falls of the Niagara and beavers which were in an original manner published in books by Louis Hennepin, in 1697, and by François of the Hollow in 1664.

At the 18th century, the cartographers started to underline the name of the original author. When they used the work of someone else, they wrote on their charts a sentence similar to this one: “according to the sketch of M. Thing”. Today, from the laws protect the royalty and defend with people to copy the work of the others.

Stages of the manufacture of a chart

First of all it is necessary to know which of the chart which one will be the subject will create, and to worry about the context in which this chart will be placed (the date will thus have its importance). A chart present in an atlas will have to be more neutral than a chart set of themes.

Then it is necessary to know on which scale will have to be carried out this chart, if information will be precise or more general (1/25 000 or 1/10 000 for example).

In general, the applicant makes a preparation with the hand with the cartographer before this one does not begin its work. However, it happens that he rests on the cartographer to make a chart with only written indications. If the cartographer requires additional, it is enough that it finds them by his own means.

On a chart, the title must summarize the information which one wishes to represent, the clear legend being, the noted scale, and the source indicated. Information must appear clearly and not be too important. The Typographie should not hide, or waste information present.

When the project of the chart is finished, the author and the cartographer meet to appreciate the modifications to be carried out, until the applicant is satisfied. Then the chart can be printed.

Modern employment

Previously, the cartographers drew the charts to realize them. Nowadays, we move towards a work either of draftsman of charts, but more directed towards an update of the already existing charts with a contribution of data, modifications of layouts. The geographical information systems and the digital model of ground are used more and more by the cartographers. The Town and country planning is a large consumer of charts. It is for this discipline that charts were designed representing the occupation of the territory such as the Corine Land Cover.

Insofar as it works out a particular representation, the cartography is also an instrument ideological and political, whose impact on the consciences, to be discrete, is often considerable. What watch particularly well a critical and comparative study of the atlas.

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