There are several methods used on the Internet (Cajthaml 2007). The best method of making Müller’s maps accessible for public is their Internet visualization. Examples of sketching of some symbols and their differences between the map of Moravia and Bohemia can be seen in Fig. We can find more kinds of towns (royal town, town with castle) more symbols of mining and processing of raw materials. The map of Bohemia, due to its bigger scale and better elaboration contains 39 symbols. The map of Moravia has 19 kinds of symbols. The map also displays rivers, main roads and relief described by “method of hills”. Legends are in Latin and in case of the map of Bohemia in German also. The author used many symbols for different types of municipalities, settlements, important institutions, and places of extraction and processing of natural resources. Other transformations were tested as well. We used affine transformation with a standard error of position of 1.23 km. A set of 83 identical points was used for the transformation of the map into the S-JTSK. Points in some areas have a similar position deviation. This is related with the used methods of measurement. Generally the problematic points were outside the Czech lands, further away and in hilly terrain. Misplaced points were ex- cluded from transformations. Co-ordinates of more than 100 points were taken. They were less important and probably lower importance was given to their field mapping and drawing. It was found that towns without walls have a generally bigger position deviation. The medieval pattern of a town with walls is well noticeable in up-to-date maps and orthophoto maps (see Fig. The use of the towns with walls as identical points seemed to be most suitable. Both variants and their combination were tested. Namely, georeferencing was done by using the network of identical points, which represented major towns and river confluences. Therefore, other method of georeferencing was chosen. The prime meridian would be almost 2 degrees to the west of Ferro. The geographical grid in Müller’s map of Bohemia does not correspond to the values common in the Czech lands. It seemed suitable to use the known map frame corners co-ordinates or the drawings of the grid for georeferencing. Notice that the non-comprimed data volume of this image has exceeded 2 GB. The edges of two adjacent map sheets were not adjusted. By this way, 25 sheets of Müller’s map of Bohemia were merged into one raster image. The difference of map section 13 between before and after merging can be seen in Fig. The result is one raster image merging every quarter without gaps. The next step was the projective transformation of every quarter. Further, it was necessary to measure each map section in 16 points (corners of quarters) and interpolate their co-ordinates. Knowing the size of a map section (557 × 473 mm) allowed us to construct a regular grid defining the map-section corners. For a seamless map creation, 100 images had to be merged into one resulting image. The gaps between the quarters were irregular. We have prints of the map which had been quartered and a cloth had been used for mounting. It can be stated that the theory of our scale determination results verified the ordinarily used value of 1:132 000 defined by Kucha r. The depiction of the local scale distortions was made as well. The resulted mean scale was computed as 1:133 000. In the next step, we again used MapAnalyst software for the map scale determination by global transformation (Helmert) with many identical points. Another method, the measuring of distances between towns in the map was done just for a few couples of towns in a test area, which resulted in a map scale of 1:132 000. 1:134 000 by careful measurement of scale bar. We determined the distance of 1 Czech mile as 68.8 mm in the map and the map scale as approx. The most probable value of one ell is 0.5914 m. We know that one Czech mile is 300 strands and one strand is 52 Prague ells. The graphic scale bar on the map of Bohemia displays two Czech miles. We determined the map scale by several methods (Cajthaml and Krej c ́ ı 2007) as well as by the previous map.
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