Friedrich Wilhelm Spehr

Friedrich Wilhelm Spehr

Friedrich Wilhelm Spehr (born November 2, 1799 in Braunschweig ; † April 24, 1833 there ) was a German mathematician , geodesist and university teacher .

Life

Spehr was the eldest son of the music dealer and publisher Johann Peter Spehr . His mother Luise, née Fischer, was the daughter of an official of the Gandersheim monastery . His younger brother was the lawyer and historian Ludwig Ferdinand Spehr .

Determined by his father to be the business successor, he had to leave high school at the age of 14 and begin an apprenticeship as a cloth merchant. Since Spehr's interests were in construction , he resisted, so that his father was forced to take him out of his apprenticeship and eventually had to take him over into his own business.

Since his father did not allow himself to be dissuaded from his intention to train him as a businessman, Spehr finally fled to Hamburg to embark for America. But he revealed himself to the ship's captain, who convinced him to return home remorseful. After Spehr's return, however, the angry father was persuaded to let his son have his way.

Spehr first prepared himself for his studies with building commissioner Kahnt together with his future brother-in-law Carl Theodor Ottmer and continued the preparation from 1817 at the Collegium Carolinum . There he discovered his interest in mathematics, so that from 1819 he began studying in Göttingen , where Carl Friedrich Gauß , Karl Ludwig Harding , Tobias Mayer and Bernhard Friedrich Thibaut were his teachers. In 1822 he returned to Braunschweig and continued his studies as a private scholar. In 1824 he received his doctorate under Carl Friedrich Gauß.

Afterwards he had difficulties in finding adequate employment and considered going abroad. Through Thibaut's mediation, he was appointed as a teacher in 1825 and as an associate professor of mathematics at the Collegium Carolinum in Braunschweig.

From 1828 to 1833 he led a triangulation of the Duchy of Braunschweig .

Spehr was involved in university politics as well as literary, for example poems by him were published in the Dresdner Abendblatt.

On July 15, 1827, he married Johanne Juliane Louise Ottmer, the daughter of a Braunschweig doctor. However, the marriage was unhappy and was dissolved again in 1832 by sovereign power after a divorce court could not find any legal reason.

Spehr's health was weakened by his private misfortune and the strains of the surveying work he carried out, so that he died of a sudden stroke at the age of 34 .

Geodetic work

Spehr was already engaged in geodesy and cartography during his studies . His father's publishing house published numerous cartographic works, e. B. 1820 a map of the Duchy of Braunschweig on a scale of 1: 280,000.

Together with Heinemann, the district taker, Spehr submitted an expert report to the duchy on August 22, 1828, which showed an exact measurement to be very advantageous. The costs were estimated at 4,725 thalers and Spehr offered to carry out the project. The project was approved on October 9, 1828. The aim of the commission he headed to correct Gerlach's special map of the Duchy of Braunschweig was to create a topographic map on a scale of 1: 50,000. In addition, Colonel von Wachholtz , Road Construction Inspector Glahn, Hofjägermeister Graf von Veltheim , Cammerrath von Amsberg and State Syndic Pricelius also belonged to the committee.

Spehr took over the execution of the survey, for which he was assigned two officers and assistants. He immediately began setting up the necessary signals for the measuring points, so that the survey could begin in the summer of 1829. In particular, measuring points and data from Gauss and a Hanoverian triangulation should be used as an aid. The least squares method is used to minimize errors .

The measurement and the calculations of the not optimally configured network progressed only with difficulty, despite the support of Gauss, in particular by providing measurement data, checking the accuracy of measurements or practical advice on measurement instruments, among other things because of adverse weather conditions. In the summer of 1830 an additional permit for 1,800 Thalers had to be applied for. Continuous delays, particularly due to Spehr's deteriorating health, led to tensions within the commission. Personal dislikes may also have played a role, because the rapid rise of Spehr had brought him envious people and enemies, and Spehr's character, especially his straightforwardness , which transgressed the boundaries of dealing, may have contributed to this. Finally, in March 1832, Spehr was forced to deliver a status report. He reported that the measurements were largely completed, but the delivery of the measurement data to the cartographers was delayed again and again until the company was completely called into question by Spehr's death.

Finally, doubts arose about the accuracy of the underlying Gerlachs'chen map, so that in 1835 the work was stopped due to a cost estimate of an additional 7900 Thalers until the map was completed. The results were archived in the ducal planning office and only reviewed again in 1857. It turned out that only two measuring points showed significant differences and deviations. However, one refrained from continuing the work, since u. a. the signals at the measuring points were also no longer available.

Mathematical work

His main mathematical work is his dissertation in the field of combinatorics : a complete teaching concept of pure combination theory with applications of the same to analysis and probability theory . This work earned him high recognition and made him one of the leading combinatorial experts in the German-speaking area.

He also wrote an extensive work on analysis , which remained unfinished due to his early death.

Education policy commitment

When Spehr became a teacher at the Collegium Carolinum in 1825 , this mainly served to train higher officials for the Duchy of Braunschweig and to prepare students for university studies. It was not a university itself and was in direct competition with the Braunschweig grammar schools (predecessor of today's Martino-Katharineum ). When in 1825 the language teacher at the Collegium Carolinum Dr. August Brandes , the pastor Friedrich Möhle and the accountant Friedrich Süpke founded a technically oriented secondary school (predecessor of today's Neue Oberschule ), which was very popular, the traditional grammar schools had to fear for their existence and the matriculations at the Collegium Carolinum also declined. A hastily convened school commission under the direction of grammar school director Friedeman and magistrate director Bode led to the consolidation of the grammar schools into a comprehensive grammar school in 1828, which further exacerbated the pressure on the Collegium Carolinum.

In 1831, in an initially anonymous publication, Spehr submitted a proposal for the further development of the Collegium Carolinum into a polytechnical institute , which was controversially discussed but initially not implemented. Spehr was way ahead of his time, only in 1862 with the conversion of the Collegium Carolinum into a polytechnic school were essential parts of Spehr's proposal implemented.

literature

• Moritz Cantor:  Spehr, Friedrich Wilhelm . In: Allgemeine Deutsche Biographie (ADB). Volume 35, Duncker & Humblot, Leipzig 1893, p. 96.
• Karl Gerke: Spehr, Friedrich Wilhelm. In: Luitgard Camerer , Manfred Garzmann , Wolf-Dieter Schuegraf (eds.): Braunschweiger Stadtlexikon . Joh. Heinr. Meyer Verlag, Braunschweig 1992, ISBN 3-926701-14-5 , p. 213 .
• Hans-Martin Arnoldt: Spehr, Friedrich Wilhelm, Prof. Dr. In: Horst-Rüdiger Jarck , Günter Scheel (ed.): Braunschweigisches Biographisches Lexikon - 19th and 20th centuries . Hahnsche Buchhandlung, Hannover 1996, ISBN 3-7752-5838-8 , p. 575-576 .

Individual evidence

1. ↑ ^{a b c d e f} Friedrich Wilhelm Spehr . In: New Nekrolog der Deutschen . tape 11 . Voigt, Weimar 1835, p. 311–318 , No. 134 ( limited preview in Google Book search).
2. ^ ^{A b} Moritz Cantor:  Spehr, Friedrich Wilhelm . In: Allgemeine Deutsche Biographie (ADB). Volume 35, Duncker & Humblot, Leipzig 1893, p. 96. or deutsche-biographie.de
3. ^ Karl Gerke: Spehr, Friedrich Wilhelm. In: Luitgard Camerer , Manfred Garzmann , Wolf-Dieter Schuegraf (eds.): Braunschweiger Stadtlexikon . Joh. Heinr. Meyer Verlag, Braunschweig 1992, ISBN 3-926701-14-5 , p. 232 .
4. ↑ ^{a b c d e} B. Pattenhausen: The development of surveying and official cartography in Braunschweig . Hofbuchdruckerei of the Jänicke brothers, Hanover 1887 ( rzbl04.biblio.etc.tu-bs.de [PDF]). rzbl04.biblio.etc.tu-bs.de ( Memento from May 1, 2018 in the Internet Archive )
5. ^ ^{A b c} Helmuth Albrecht: Between traditionalism and reorientation: The path of the Braunschweiger Collegium Carolinum to the polytechnic school (1814–1862) . In: Günter Scheel (Ed.): Braunschweigisches Jahrbuch . tape 63 , 1982, pp. 53-88 ( archive.org [PDF]).
6. ^ Friedrich Wilhelm Spehr: Topographical chart of the Herzogthume Braunschweig . Braunschweig 1820 ( Kulturerbe.niedersachsen.de ).
7. ↑ Hans-Martin Arnoldt, Kirsten Casimir, Uwe Ohainski (eds.): The Gerlach map of the Principality of Braunschweig-Wolfenbüttel (=  publications of the Historical Commission for Lower Saxony and Bremen . No. 235 ). Hahnsche Buchhandlung, Hannover 2006, ISBN 3-7752-6035-8 .
8. ↑ Carl Friedrich Gauß: 20. Six letters to Friedrich Wilhelm Spehr about the Brunswick land survey 1828–1832: Measurements of Brunswick points and connection to neighboring triangles . In: Works . 12: Varia. Atlas of Earth's Magnetism . Dieterichsche Universitäts-Druckerei W. Fr. Kaestner, Göttingen 1929 ( deutsche-digitale-bibliothek.de ).
9. ↑ ^{a b} Wolfgang Torge: History of geodesy in Germany . W. de Gruyter, Berlin 2007, OCLC 5894466249 , p. 180-181 .
10. ↑ Friedrich Wilhelm Spehr: Complete concept of pure combination theory with applications of the same to analysis and probability theory . Braunschweig 1824 ( tu-braunschweig.de ).
11. ^ Friedrich Wilhelm Spehr: New principles of the fluenten calculus. Containing the principles of the differential and the calculus of variations independent of the ordinary fluxion method, of the concepts of the infinitely small or of vanishing quantities, of the method of limits and the theory of functions; at the same time presented as a textbook of this science, and connected with applications to analytical geometry and higher mechanics . tape 1 . Meyer, Braunschweig 1824.
12. ^ Letter from a Braunschweig resident to a friend from abroad regarding the establishment of a university or a polytechnic institute in Braunschweig . Braunschweig 1831.