Royal Saxon triangulation
The Royal Saxon Triangulation (here with the historical proper name ) is a land survey carried out in the years 1862 to 1890 on the territory of the Kingdom of Saxony with the simultaneous creation of a trigonometric network.
The aim was to precisely record the national territory scientifically and geodetically and to create the basis for the production of accurate maps by defining permanently marketed fixed points . The Grossenhainer baseline was determined as the benchmark .
Network structure
The triangulation network comprised a total of 158 first and second order stations . This made it one of the tightest and most progressive in Europe at the time. The 29 points of the 1st order had a mutual distance of 30 to 50 kilometers (on average 40 km), those of the 2nd order of around 20 km. The 1st order stations were used to measure Central European degrees , while the 2nd order stations were also used for Saxon triangulation.
The surveying network covered around 16,000 km² (today's area of Saxony 18,420 km²). The longest side of the network measures 53 km, on the southern border some network diagonals of up to 60 km in length could be observed over Bohemian territory.
Extension to the meridian arc
Soon after the start of work, it was agreed with Austria-Hungary to connect the triangular network close to the border around the standard Großenhain baseline to the south with the Bohemian surveying network. Due to the Austro-Prussian War that broke out in 1866 , the project stalled for a long time, but eventually even became part of the 700 km long meridian arc Grossenhain-Kremsmünster-Pola .
calculation
The position of the measuring points A and B is known, thus also their distance (distance c). The position of point C is to be determined. The angle between line AB and line AC is measured from position A by means of a target disk or theodolite . The angle is also measured from position B. The length of the unknown distances a and b is calculated as follows: a = c * sin / sin and b = c * sin / sin . The intersection of the circles drawn around A and B with radius b and a is position C. Of course, this measuring method requires that all points are freely visible. Many of the mountain peaks used for triangulation at that time, however, were significantly less forested than today and visual connections to other stations also had to be made possible by cutting aisles. Today many of the triangulation pillars' locations are largely overgrown.
The measurement of an angle with a theodolite is, like all optical measurement methods, always fraught with inaccuracy. One will therefore try to carry out the measurements from more than two known points and place the point sought in the middle of the results obtained.
Triangulation columns
The triangulation pillars are listed as technical monuments (totality of the Royal Saxon Triangulation ["European degree measurement in the Kingdom of Saxony"]).
1st order stations
The fixed points are each about 50–60 kilometers away from the nearest located. At the time of the measurement, at least three further stations of the same order were directly observable from each first-order station, i.e. the sightings were clearly visible.
Map with all coordinates of the 1st order stations: OSM
No. | station | comment | Geographical location | photo |
---|---|---|---|---|
1 | Ossling | Pillar moved from the summit of the Oßlinger Berg to the village of Oßling because of a quarry in 1994 ( 51 ° 21 ′ 36 ″ N, 14 ° 9 ′ 59 ″ E ) | 51 ° 21 ′ 40 "N, 14 ° 9 ′ 26" E | |
2 | Nostitzhöhe | hill located east of Groß Radisch ; Column first erected in 1863, destroyed by storm damage in 1868; Brick pillars of unknown date in different location, re-erected near the monument; see Monumentberg , JCAvNostitz | 51 ° 15 ′ 25 ″ N, 14 ° 42 ′ 15 ″ E | |
3 | Jauernick | on the Black Mountain , then the province of Silesia | 51 ° 5 '39 "N, 14 ° 53' 51" E | |
4th | Jeschken | in Bohemia, today Ještěd the Austrian pillar that was used in 1867 is no longer there today |
50 ° 43 ′ 58 "N, 14 ° 59 ′ 6" E | |
5 | Listen | The surveying column was dismantled in 1941. | 50 ° 50 ′ 56 "N, 14 ° 38 ′ 49" E | |
6th | Valtenberg | The triangulation point is located on the observation platform of the observation tower. | 51 ° 4 ′ 27 "N, 14 ° 16 ′ 43" E | |
7th | Porsberg | on the Borsberg near Dresden | 51 ° 0 ′ 46 ″ N, 13 ° 54 ′ 12 ″ E | |
8th | Schneeberg | High Snow Mountain (Bohemia, today Děčínský Sněžník ), stone survey point on the observation platform of the tower no longer exists | 50 ° 47 ′ 35 "N, 14 ° 6 ′ 31" E | |
9 | Kahleberg | The tower for the triangulation pillar was demolished in 1962. | 50 ° 45 ′ 6 ″ N, 13 ° 44 ′ 1 ″ E | |
10 | Keulenberg | The triangulation column is built over with the observation tower. | 51 ° 13 ′ 38 "N, 13 ° 57 ′ 22" E | |
11 | shrub | on the Heidehöhe near Strauch (Grossenhain) | 51 ° 23 ′ 5 ″ N, 13 ° 34 ′ 31 ″ E | |
12 | Baeyerhöhe | Hill near Klipphausen named after the geodesist Johann Jacob Baeyer , one of the founders of European grade measurement. The column was moved about 4 meters in 1999. | 51 ° 4 ′ 28 "N, 13 ° 27 ′ 58" E | |
13 | Udo height | near Oederan, the pillar is now about 25 m further north. | 50 ° 52 ′ 58 "N, 13 ° 9 ′ 32" E | |
14th | Amber | on the Amber Hill (Bohemia, today Medvědí skála ) remains of the brick pillars are present. |
50 ° 34 ′ 14 "N, 13 ° 27 ′ 52" E | |
15th | Fichtelberg | Due to the new construction of the Fichtelberghaus in 1965, the column was moved around 80 m to the south. | 50 ° 25 ′ 42 "N, 12 ° 57 ′ 15" E | |
16 | Pfaffenberg | near Hohenstein-Ernstthal, on the Pfaffenberg behind the new elevated water tank that is currently under construction | 50 ° 48 '43 "N, 12 ° 43' 22" E | |
17th | Rochlitz | On the Friedrich August II tower on the Rochlitzer Berg | 51 ° 1 ′ 36 ″ N, 12 ° 46 ′ 15 ″ E | |
18th | Collm | On the Albert Tower on the Collmberg | 51 ° 18 ′ 13 ″ N, 13 ° 0 ′ 38 ″ E | |
19th | Hohburg | on the Löbenberg , after 1930 the pillar was removed | 51 ° 25 '13 "N, 12 ° 47' 44" E | |
20th | Leipzig | Pillars A, B and C on the tower of the demolished Pleißenburg | 51 ° 20 ′ 11 "N, 12 ° 22 ′ 21" E | |
21st | Röden | near Zeitz , on the road between Röden and Kuhndorf, then in the province of Saxony |
51 ° 1 ′ 9 ″ N, 12 ° 8 ′ 59 ″ E | |
22nd | Remorse | on the Reuster Berg, near Ronneburg, Thuringia | 50 ° 49'53 "N, 12 ° 11'43" E | |
23 | Kuhberg | at Brockau | 50 ° 35 ′ 57 ″ N, 12 ° 13 ′ 19 ″ E | |
24 | Aschberg | near Klingenthal on the Aschberg (Bohemia, today Kamenáč) | 50 ° 23 ′ 22 "N, 12 ° 30 ′ 32" E | |
25th | Kapellenberg | at Bad Brambach the column is in the observation tower |
50 ° 11 ′ 17 ″ N, 12 ° 18 ′ 2 ″ E | |
26th | Stilts | west of Plauen the original column no longer exists |
50 ° 29 ′ 18 ″ N, 11 ° 56 ′ 59 ″ E | |
27 | Dobra |
Franconian Forest , Bavaria the observation pillar no longer exists |
50 ° 16 ′ 42 "N, 11 ° 38 ′ 35" E | |
28 | Ox head | Fichtel Mountains , Bavaria | 50 ° 1 ′ 51 ″ N, 11 ° 48 ′ 36 ″ E | |
29 | Buchberg | on the Hinterer Buchberg southwest of Königsbrück in the Laußnitzer Heide | 51 ° 14 ′ 3 ″ N, 13 ° 50 ′ 6 ″ E | |
30th | Grossdobritz | on the Hegelsberg | 51 ° 12 ′ 35 "N, 13 ° 34 ′ 0" E | |
31 | Baselitz | southwest of Priestewitz | 51 ° 14 ′ 23 "N, 13 ° 28 ′ 29" E | |
32 | Großenhainer baseline | Base end transverse | 51 ° 18 ′ 45 ″ N, 13 ° 37 ′ 15 ″ E | |
33 | Grossenhain base center , original from 1869 lost, reconstructed in 2006 as 33n with offset | 51 ° 18 ′ 18 ″ N, 13 ° 33 ′ 15 ″ E | ||
34 | Raschütz base end | 51 ° 17 ′ 53 "N, 13 ° 29 ′ 42" E | ||
35 | Weida | west of Riesa | 51 ° 17 ′ 44 "N, 13 ° 14 ′ 54" E | |
36 | Freiberg | Inkwell , remains of the former observatory on the Upper Forest Trail | 50 ° 54 ′ 5 ″ N, 13 ° 19 ′ 29 ″ E |
2nd order stations
Within the first-order triangular network consisting of 36 stations, a more closely-meshed second-order network with 122 fixed points was established at the same time. The 2nd order points are about 20 km apart.
Map with all coordinates of the 2nd order stations: OSM
See also
- Johann Jacob Baeyer (1794–1885), founder of the European degree measurement
- August Nagel (1821–1903), his life's work was the Royal Saxon Triangulation
literature
- Interest group Nagelsche Säulen and Staatsbetrieb Geobasisinformation und Vermessung Sachsen (Ed.): Historical surveying columns in Saxony - a search for clues . Schütze, Engler, Weber, Dresden 2012, ISBN 978-3-936203-18-9 ( publisher's website ).
- Sven-Eric Fischer: Investigations into surveying cultural monuments in Saxony - example of the Porsberg station column of the Central European degree measurement . AV Akademikerverlag, Saarbrücken 2014, ISBN 978-3-639-49659-8 , p. 80 ( publisher's website ).
- Rainer Nitzsche: 1862–2015 - 150 years of degree measurement in Saxony (= Sächsische Heimatblätter . No. 1 ). 2012, p. 13–17 ( slub-dresden.de [PDF; 1,2 MB ; accessed on August 15, 2018]).
Web links
- 150 years of Nagelsche Säulen In: Preview Review, July 1, 2012, accessed on August 4, 2020.
- Gunter Trentzsch's website
Individual evidence
- ↑ They can be identified by means of the appendix to the large inquiry Drs. 6/5471 (as of June 24, 2016).
- ↑ Thomas Quaiser: Stations of Central European Degree Measurement and the Royal Saxon Triangulation in Saxony 1862-1890. (No longer available online.) Www.primacom.net, July 19, 2013, archived from the original on September 2, 2013 ; accessed on August 15, 2018 . Info: The archive link was inserted automatically and has not yet been checked. Please check the original and archive link according to the instructions and then remove this notice.