Struve had purchased the Troughton sextant already when he was a home teacher in the Berg’s manor in Sangaste. During the war of 1812 he was considered to be the French Spy and he was sent to the Pärnu military court. One Troughton sextant has also reached the museum (TÜAM, photo T. Pung).

First geodetic expeditions on the territory of Estonia

On the territory of Estonia the first geodetic expedition was the mapping of the River Emajõgi by Magnus Georg Paucker in 1808–1809 the result of which was published only in 1855.

In the summer of 1808 the River Emajõgi was surveyed. The results were printed in 1855 (TÜR, 55-201: 40-41).

It was followed by the geodetic measurement of Livonia, commissioned by the Livonian Society of Generally Useful and Economic Affairs from Tartu University and it was carried out by F. G. W. Struve in the years 1816–1819. The work was done for making an exact topographical map of Livonia which was necessary for the development of economic life including the implementation of the provisions of the Law on the Livonian Peasantry which demanded that the taxation of the farms should be in conformity with the size and the quality of their land. Because of the resistance of the local landlords – they were afraid of the new governmental taxes – Carl Gottlieb Rücker (1778–1856) completed the map only in 1839.

On the basis of the triangulation of Livonia Carl Gottlieb Rücker (1778-1856), the cartographer, made a new more exact general map of Livonia (1836) and a special map of Livonia in 6 sheets (1839). Most of the maps of the 19th century were made on this basis (RR: The collection of maps)