Kymograph
A kymograph ("wave recorder") is a device for graphically recording a position over time. It consists of a rotating roller with stretched (sooty) paper on which a writing instrument or stylus is moved by changing its position in a sensor mechanism and records traces.
The first kymograph goes back to Thomas Young , who presented his self-made model in 1807 in the text A course of lectures on natural philosophy and mechanical arts . The physiologist Carl Ludwig also developed a kymograph in the 1840s, initially for the purpose of intrusive blood pressure measurement . The devices were also used to record muscle contractions and other physiological movement processes, as well as sound analysis. In contrast to the phonograph , it was not a question of the reproducibility, but only the graphic representation of the sound waves .
With his kymograph, Carl Ludwig had a great influence on the further development of physiology . Within a few years, “first by German physiologists, then especially by Marey in France, a large number of self-registering devices were developed and used in physiological research”.
Web links
- Kymograph in the virtual laboratory (see data sheet tec2206 )
- O. Frank: Kymographs, writing levers, registration mirrors, principles of registration. In: Robert Tigerstedt (Hrsg.): Handbuch der Physiologische Methodik , I. Volume. Hirzel, Leipzig 1911
- Marey, Étienne Jules . 1878. La méthode graphique dans les sciences expérimentales et principalement en physiologie et en médecine . Paris: G. Masson (French, accessed September 20, 2012)
- Langendorff, Oskar : Description of the most important registration apparatus: The Ludwig-Baltzar'sche cylinder . In: Langendorff, Oskar. 1891. Physiological graphics: A guide to the registration methods used in physiology. Leipzig, Vienna: Deuticke (accessed on September 20, 2012)
Individual evidence
- ↑ Cf. for example kymograph according to Ludwig and Baltzar (before 1890), Harvard University, Collection of Historical Scientific Instruments (English).
- ↑ Contribution to the program “ Forschungs aktuell” from Deutschlandfunk : Devices for researching human language. The acoustic-phonetic collection of the University of Dresden (December 22, 2008; accessed February 20, 2011).
- ↑ Soraya de Chadarevian: The “method of curves” in physiology between 1850 and 1900. In: Hans-Jörg Rheinberger , Michael Hagner (ed.): The experimentalization of life. Experimental systems in the biological sciences 1850/1900. Berlin 1993, p. 29.