The 1912 ordnance survey map follows the tradition of the preceding maps of 1834 and 1859/1860. However, the resulting map differs little from today's official German maps of the same scale. As with the previous maps, further developments concerned technical, staff-related and organisational elements of the production process. These developments were supported by the internationalisation and the connection with other surveying scientists, which enabled an exchange of data and techniques.
The internationalisation of surveying science was promoted from the second half of the 19th century onwards. In particular, the former Chief of the Trigonometric Department of the General Staff Johann Jacob Baeyer (1794-1885) promoted international exchange after his term of office. He played a leading role in organising the necessary coordination, which led to an "International Earth Measurement" first among the European states and then worldwide. In the process, the focus of earth measurement shifted from determining the valid ellipsoid of rotation to determining the respective deviations of the local gravitational field from the ellipsoid of rotation.
At the same time, surveying science established itself as an independent science that went beyond practical land surveying. This influenced the training of surveyors, who were recognised as a distinct profession with special requirements. In addition, the increase in knowledge and cooperation interconnected the various branches of surveying in Prussia and the German Empire more closely. Previously, they had been decentralised into the Land Surveying, which was carried out by the General Staff, the Cadastral Administration, which was subordinate to the Ministry of Finance, and another department, which was subordinate to the Ministry of Agriculture, Domains and Forests. This fragmentation was to be counteracted by the Central Directorate of Surveys in the Prussian State as a coordinating body. It therefore also took over the management of the Land Survey. The Central Directorate introduced a standard height vertical datum called "Normalhöhennullpunkt" and ordered a new survey of two-thirds of the state territory. After the turn of the century, this new triangulation was also initiated for the areas east of the Elbe, from which the map presented here also originates.
The most important reformer of the organisation of the Land Survey and its technical regulations at this time was the officer Oscar Schreiber (1829-1905), who was head of the Trigonometric Department of the Land Survey from 1888 to 1893. Schreiber was dissatisfied with the basics of the computational methods and had created new methods and standards on a scientific basis, which significantly increased the quality of the new maps. He started from the foundations laid by Carl Friedrich Gauß (1777-1855) and Friedrich Wilhelm Besse (1784-1846) and developed applicable methods for land surveying from these.
New instruments, which provided more accurate results and were easier to use, were also part of the improvement of this period. In addition, the technique of height measurement was improved and comprehensively defined such that there was now a uniform survey image in three dimensions. During the same period there were improvements in the design of the maps and their standardisation and duplication., As a result, the 1912 map is a reliable and very dense medium of information. These improvements can be seen very clearly on the map. The clear contours and the landscape and settlement elements depicted with few means give a good and clear impression of the landscape at the time of mapping, which can be easily transferred to a present-day WebGIS.
Works Cited
Torge, Wolfgang (2002): Müfflings geodätisches Wirken in der Umbruchepoche vom 18. zum 19. Jahrhundert. In: Zeitschrift für Vermessungswesen (ZfV) 127, pp. 97–108.
Torge, Wolfgang (2009): Geschichte der Geodäsie in Deutschland. 2. ed. Berlin: de Gruyter.