Jan Evangelista Purkyne
Czech physiologist, 1787-1869
"Jan Evangelista Purkyně was a Czech anatomist and physiologist. In 1839, he coined the term ""protoplasm"" for the fluid substance of a cell. He was one of the best known scientists of his time. He is best known for his 1837 discovery of Purkinje cells, large neurons with many branching dendrites found in the cerebellum. He is also known for his discovery in 1839 of Purkinje fibres, the fibrous tissue that conducts electrical impulses from the atrioventricular node to all parts of the ventricles of the heart. Purkyně was the first to use a microtome to make thin slices of tissue for microscopic examination and was among the first to use an improved version of the compound microscope."
Source: Wikipedia
Physiologe (1787-1869). Autograph quotation signed ("Prof. Dr. Joh. Purkyne"). Prag. 06.04.1864. 1 S. Qu.-Kl.-8vo.
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"Gang- und gäbe Phrasen unseres constitutionellen Zeitalters. || Das Princip - ist die Theorie, die Moral, das Sollen - die Tugend | Praxis, Op[p]ortunität, führen zum fait accomplit. | Führen gar oft zur Sünde, zum Unglück, zu grausem Verbrechen, | Doch des Frommen Sinn sieht nur das Gute darin. | Wenn das Meer im Frieden dahinwallt, glaubst du, der Sturm wars | Welcher die Flotte verschlang, der nun den Frieden gebracht? | Doch ists wahr: die Menschheit erhebt sich stets jung aus dem Tode, | Und wer das Leben gewann freut sich des goldenen Lichts [...]".
- Purkinje is known for his discovery of Purkinje fibres, the fibrous tissue that conducts electrical impulses to all parts of the ventricles of the heart. Other discoveries include Purkinje images, reflections of objects from structures of the eye, and the Purkinje shift, the change in the brightness of red and blue colours as light intensity decreases gradually at dusk. Purkyne also introduced the scientific terms "plasma" and "protoplasm". During the last years of his life (from which thre present quotation dates), Purkinje "repeatedly stressed the importance of science and knowledge in practical life. His work [...] was of great importance in the Czech national revival and exerted a lasting effect on the subsequent development of science in his country" (DSB XI, 217)..