August rapeseed

August Raps (born January 23, 1865 in Cologne , † April 20, 1920 in Berlin ) was a German physicist who invented the mercury expansion air pump named after him, the Rapssche pump .

Life

As the son of the painter Friedrich Raps , he studied physics in Bonn and Berlin, where he was August Kundt's assistant at the Physics Institute and invented his "Automatic Mercury Air Pump ", which was presented in the Zeitschrift für Instrumentenkunde (11) in 1891 , which was used in the early industrial manufacture of light bulbs played an important role. It essentially corresponds to a Geissler - Toepler mercury air pump , supplemented with an automatic control of the mercury flow.

With a Jamin interferometer he photographed the air vibrations in gedackten pipes.

In 1891 he became a private lecturer at the university and from 1893 worked at Siemens. In 1895 he developed a braking device to synchronize the transmitter and receiver of the Hughes telegraph system . The fact that the receiver runs a little faster than the transmitter reduces the risk of signal loss.

Grave of August Raps in the south-west cemetery in Stahnsdorf

In 1897 he was entrusted with the management of the Siemens cable factory on Franklinstrasse in Charlottenburg, and from 1905 he and Adolf Franke also managed the Wernerwerk F in Berlin-Siemensstadt, which was newly built for the mass production of telecommunications equipment and measurement technology . Raps was a member of the board of directors of Siemens & Halske from 1900 to 1919 . In 1900 the technology-loving Cologne chocolate producer Ludwig Stollwerck made contact with Ferdinand Braun and the telegraph construction company Siemens & Halske took over the construction of Braun'scher apparatus. At the end of 1898, Stollwerck founded a consortium in Cologne for the exploitation of Braun's patents and brought in 560,000 marks in company capital. After reaching radio communication over a greater distance, the consortium was converted into "Professor Braun's Telegraphie Gesellschaft GmbH", from which Telefunken AG later emerged. Raps played a key role in promoting the introduction of the direct dial telephone service .

From 1900 to 1920 Raps taught as a professor for electrical engineering at the TH Dresden . His grave is in the south-west cemetery Stahnsdorf .

Works

• For the objective representation of the sound intensity ; Leipzig, Barth, 1889
• About air vibrations ; 1893
• About electrical measurements and measuring instruments; Lecture given on November 18, 1902
• Electricity and welfare ; Berlin, Stilke, 1913

literature

• Hermann Gocht: August Raps +. Advances in the field of x-rays ; Vol. 27, pp. 560/561, 1919-1921
• EMS: August Raps - co-designer of the Wernerwerk . District news; Berlin September 1987
• Karl HP Bienek: Siemensstadt Lexicon - Streets in Siemensstadt . ERS, Berlin 1992.
• Adolf Franke: August Raps. Dr. phil. Dr.-Ing. n. G., Professor, Director of Siemens [and] Halske A.-G. born Jan 23, 1865, d. Apr. 20, 1920 ; Berlin, Springer, 1921
• Lothar Schoen:  Rapeseed, August. In: New German Biography (NDB). Volume 21, Duncker & Humblot, Berlin 2003, ISBN 3-428-11202-4 , p. 154 f. ( Digitized version ).

Web links

• Literature by and about August Raps in the catalog of the German National Library

Individual evidence

1. ↑ Christoph Meinel, University of Regensburg: Rühmkorff, Röntgen, Regensburg: Historical instruments for gas discharge. Seminar project, 1997
2. ↑ Ludwig Darmstaedter: Handbook on the History of Natural Sciences and Technology 1866 (PDF; 2.8 MB)
3. ↑ Anton A. Huurdeman: The Worldwide History of Telecommunications .
4. ^ Siemensstadt-Lexikon: August Raps ( memento from January 6, 2014 in the Internet Archive ), accessed on January 6, 2014.
5. ^ University archive TU Dresden: Prof. Dr. phil. August rapeseed