Jan Evangelista Purkyně

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Lithograph of Purkyně by Rudolph Hoffmann, 1856, after a photograph by Bertsch & Aaraud, Paris.
Born December 18, 1787(1787-12-18)
Libochovice, Bohemia, Austrian Empire
Died July 28, 1869(1869-07-28) (aged 81)
Prague, Austria-Hungary
Drawing by Jan Vilímek, in Zlatá Praha, Vol 4, No 37, 1887.[1]
Illustration by František Bílek, in Sebrané spisy, Vol. 1, 1918.

Jan Evangelista Purkyně (Johann Purkinje) was a 19th-century physiologist, anatomist, biologist, poet and philosopher. His experimental physiological investigations in the fields of histology, embryology and pharmacology helped to create a modern understanding of the eye and vision, brain and heart function, mammalian reproduction and the composition of cells. In his early work he built upon Ernst Chladni's research on sound figures and JW Goethe's studies of perception as well as synaesthetic phenomena. Later he experimented with representation of movement using his own machines (Phorolyt, Kinesiscope). Purkyně created the world's first department of physiology and was one of the best known scientists of his time. He was a member of the Academies of Sciences in Berlin (1832) and Vienna (1860), of the Royal Society in London (1850), and corresponding member of the Academies of Sciences in St. Petersburg (1836) and Paris (1861).

[edit] Life

[edit] Early years

J. E. Purkyně was born on 17 or 18 December 1787 in Libochovice, a small village in northern Bohemia (then part of the Austrian Empire, now Czech Republic), as the first son of economic supervisor of the estate of Dietrichsteins, Josef (1746–29.9.1793) and Rosalia (born Šafránková, 1756–1834) Purkyně, followed by Emanuel (24.12.1789-28.5.1791) and Josef Jindřich (12.7.1793–1833). His father died suddenly in 1793. This affected the economic status of the family, and Jan's opportunity to acquire higher education was endangered.[1][2][3]

Early studies

Jan received the foundations of general education in the Czech primary school of Libochovice. The inquisitive child widened his horizons by reading Comenius' Orbis Pictus. The local chaplain, Father Schiffner, was impressed by the child's intelligence and introduced him to Latin. He also taught him the Greek alphabet and spoke with him about astronomy. In the school Jan was introduced to music, both vocal and instrumental. He sang well and learned to play violin. As it turned out, these skills, especially singing, were of critical importance for the continuation of his education.[4][5]

In the spring of 1798, with the help of his mother's friends, Jan was accepted as a member of the church choir in Mikulov, southern Moravia. This enabled him to attend the school (later followed by his brother Josef), established for the Piarist order by Cardinal Dietrichstein, without paying the relatively high tuition fees. The language of instruction was German. The study program involved 3 years of the so-called normal school and 5-year gymnasium. At the gymnasium, the curriculum included Latin, Greek, history, and geography. In contrast to other comparable schools, at this gymnasium the Piarists paid substantial attention to philosophy, modern languages, mathematics, and physics. The Mikulov school had a rich collection of astronomical and physical apparatus. In its library he acquainted himself with the writings by G. Dobner and S. Konarski. There he probably found Schiller's poems, his lifelong passion. Jan did well in the normal school and was one of the best students at the gymnasium; he completed his studies there in 1804.[6][7]

Purkyně's signature in 1806.

In order to be able to continue his schooling, Purkyně applied for admission to the Piarist order, was accepted and adopted name Silverius. For his novitiate he journeyed to the monastery Stará Voda, near Olomouc, in north-central Moravia. Here he strengthened his knowledge of some subjects that were taught in the gymnasium and also learned French and Italian, completing his studies in two instead of three years. In 1805 he began to teach at the Piarist school (nižší gymnázium) in Strážnice (where Jan Amos Comenius studied in his time), southern Moravia, and in the following year he moved to the Piarist college in Litomyšl, eastern Bohemia. During the school year 1806–7 he simultaneously taught at the normal school and studied philosophy; the latter was at a school training future gymnasium teachers as well as students planning to study law, medicine, or theology. The library of the monastery of Olomouc offered rich treasures; among the major German thinkers, Kant remained unappealing to Purkyně whereas Schelling's Naturphilosophie [Philosophy of Nature] interested him throughout his life; however, it was Fichte who affected him most profoundly, especially through Einige Vorlesungen über die Bestimmung des Gelehrten [Some lectures on the mission of a scholar] (1794) and Uber die Bestimmung des Menschen zur unbeschränkten seelischen Freiheit [The call of men to an unlimited mental freedom] (1800).[8][9]

The German philosophers were not the most appropriate reading matter for a thoughtful young cleric who was a member in the Piarist order. Purkyně himself, in his midseventies, remembered the impact of Fichte’s philosophy as follows: "Having become somewhat familiar with the state of the newer literature in Germany and in other cultured countries and admiring their top contributors as well as getting to know the fate of my aging colleagues in the monastery, exhausted from an early age by strenuous teaching, I was frightened that a similar fate would await me as well"[10]. Fichte's philosophy vividly portrayed the mission of a true scholar in human society and rallied the human mind to an unlimited freedom. In combination with this familiarity with Fichte, Purkyně began to think of a different, happier life with enough strength to establish an independent position in the world: "Yes, the desire of glory strongly impelled me to follow my own path. Having been concerned in the monastery only with philological and historical studies, I turned first to poetry and then to philosophy whose spirit would free my mind. Yes, I felt deeply that I could achieve something significant in natural sciences, about which of course I had only a vague idea"[11]. These thoughts moved Purkyně to leave the Piarist order in August 1807, after which he took a pilgrimage walk home (Litomyšl, Vysoké Mýto, Přelouč, Praha, Radovesice, Libochovice). The chronicle of the monastery at Litomyšl contains a brief record of his decision: "Clericus Silverius Purkinie deserto Instituto nostro ad parentes Libochovicium migravit" (Having left our institution, the Clericus Silverius moved to his parents in Libochovice).[12][13]

[edit] First Prague period (1807–23)

Hildprandt's castle in Blatná. Purkyně often stayed here also during his medicine studies in Prague, studied visual phenomena and used its library.
Studies

In 1807–9 Purkyně studied in the second and the third years of the philosophical faculty of the University of Prague (then Universitas Carolo—Ferdinandea). His interests were turning more and more toward the natural sciences. In his old age he noted that physics was his first love. In the second year he completed a manuscript on Ernst Chladni's sound images and handed it into his professor of physics, F.Schmidt, who was director of the Physical Institute of the Faculty of Philosophy. Purkyně returned to the subject more than 10 years later. During the summer holidays of 1808 Purkyně first met his lifelong friend Josef Jungmann in Litoměřice. Among the teachers of the faculty of philosophy, the botanist and mineralogist Jan Emanuel Pohl, an adherent of Naturphilosophie, had the most influence on him. Purkyně was making his living by tutoring in the families of Barons Schuterstein and R. Weitenweber, however after completing the third year of his studies (1809), he experienced financial difficulties preventing him from continuing the studies. Pohl recommended him as tutor to the son of the Baron Franz Hildprandt, owner of properties in Blatná, south-western Bohemia. There, Purkyně spent three rewarding years (1810–13) in a cultured environment and with possibilities of studying in the rich library of the castle.[14][15][16]

The ideas of Novalis and the writing of the Swiss pedagogue Pestalozzi stimulated Purkyně's interest in institutions in which children were to be educated by outstanding teachers, without the “disturbing impact of the families.” In fact, in Blatná he played with the idea of creating just such an institution. As Purkyně later recalled, in such an institution the children would receive multifaceted training, including handicrafts, trades, and arts, but also experimentation and the use of instruments. Their physical, intellectual, emotional, and motivational development would be influenced in practical ways, as specified by Pestalozzi. Purkyně did not pursue the idea of such a career. Thanks to the financial assistance provided by his former employer, in November 1812, Purkyně was able to enter the medical faculty of the University of Prague.[17]

Prague's hospital U Milosrdných which hosted clinical part of Purkyně's medicine studies.[2]

The medical faculty operated at a contemporary international level of natural and medical sciences. Prominent among his teachers were the anatomist Johann Georg Ilg, physiologist and ophthalmologist Josef Rottenberger, and Andreas Wawruch, a pathologist and teacher of materia medica, the science dealing with the nature and properties of substances used in treating diseases. Ilg was a believer in empirical knowledge in contrast to speculations, and he taught anatomy with his own textbook, Grundlinien der Zergliederungskunde des menschlichen Körpers (1811), published at the very start of his teaching at the medical faculty of Prague. He was well known for his skillful autopsies and for preparation of anatomical teaching specimens. Rottenberger lectured on physiology and, more importantly for Purkyně's scientific career, ophthalmology. These lectures contributed to the his choice of vision as the topic of his doctoral dissertation. Another important factor for Purkyně's professional career was his contact with I. Fritz, a skillful and original surgeon. Purkyně learned from him basic operational techniques (working as a trainee at his clinic in 1816–18), but also gained his personal friendship. Fritz supported Purkyně's subsequent search for employment that would permit him to put to use and further develop his talent for scientific research. The lectures of Wawruch on materia medica inspired Purkyně to examine the impact of physiological experiments and medicaments on himself (e.g. physiological changes during three-day long hunger strike, or processes of incipient freezing).[18]

Subjective visual phenomena, in Beiträge zur Kenntniss des Sehens in subjectiver Hinsicht, 1819, p 178.[3]

It was in 1818 that Fritz and Wawruch brought Purkyně to the attention of the Professor of Surgery, J.V.Rust, in Berlin. Rust supported the nomination of Purkyně for a Prussian travel fellowship, with the prospect of a professorship in veterinary science. Purkyně did not accept the offer, as he decided, at Hildprandt’s suggestion, to complete his medical studies by defending a doctoral dissertation. Nevertheless, he acquired in Rust a significant protector. Purkyně's defense of his dissertation, Beiträge zur Kenntniss des Sehens in subjektiver Hinsicht, took place on 30 November 1818. It appeared in print in Prague in 1819 and again in 1823.[19][20][21] He was familiar with Goethe's Beiträge zur Optik (1791/92)[15] and Zur Farbenlehre [Theory of Colours] (1810)[16] and although he did not explicitly refer to him, in his dissertation he confirmed with experiments some of his observations on so called "physiological colours" [physiologische Farben], previously refused as unscientific.[22][17](p39)

Teaching

The years to come were full of intense studies and research concentrated on sensory organs and their functions. In January 1819 he joined the Department of Anatomy of the Prague University as prosector and research assistant of Prof Ilge and Prof Rottenberg. He unsuccessfully applied for professorships at several departments in Prague (pharmacology, 1820), Budapest (anatomy, 1820), Graz (anatomy and physiology, 1822), and Ljubljana (anatomy).[23][24]

Professional affiliations and activities

With Josef Jungmann and Jan S. Presl he co-founded magazine Krok. He was a member of a secret society, most probably Illuminati.[25]

In 1821 he traveled to Dresden. In 1822, together with Presl brothers, he secretly traveled to Leipzig to attend the First Congress of German Natural Scientists and Physicians (18–23 September). There he met state councillor Ch. F. Schulz (via Berlin professor J. N. Rust) who later introduced him to J. W. Goethe. Purkyně then visited Goethe in Weimar on 10–12 December; Goethe was already familiar with his Dissertation and later published an extensive review of it, clearly impressed by the subtlety of Purkyně's vision because he wrote "we are grateful to the author for undertaking this task and for raising it to a new level" (1824)[26].[27] In 1823, Goethe wrote in his letter to Count Sternberg on his address: "an unusually excellent man; an autodidactic and heautomorumentic spiritual and brilliant piarist"[28]. The two exchanged letters until Goethe's death in 1832[18]. At the Congress Purkyně also met Karl Asmund Rudolphi, Berlin professor of anatomy and physiology, who personally intervened to Minister Altenstein for Purkyně's professorship in Breslau, Prussia (today Wrocław, Poland).[29][30]

[edit] Professorship in Breslau (1823–50)

University of Breslau. [4]

In January 1823, King Friedrich IV of Prussia made Purkyně--against the strong opposition of the medical faculty--professor of physiology at the Medical Faculty of the University of Breslau. It was one of the most surprising university appointments of the time, for the young Czech had not even the title "Dozent" to his name and only a few little noticed publications.[31]

The 27 years spent in Breslau was the most fruitful period of his life. His intensive investigative charge and a wide action radius of research interests brought him a rich harvest of original results in various fields of physiology which today corresponds more to the concept of biology.[32][33]

Visual vertigo and flashing lights after the use of foxglove (38–42), concentric circles and rays for testing of the myopic eye (44–45), axis of the short- and long-sighted eye for an explanation of strabismus (46), or explanation of inverted movements of an object (pin) in front of an image near the eye (47–49). In Neue Beiträge zur Kenntniss des Sehens in subjectiver Hinsich, 1825, p 54.[5]
Teaching

After visiting Berlin in March, on c10 April 1823 he began lecturing physiology (5 times a week) and pathology of eye a psychology (twice a week), although the lectures were poorly attended. Stayed in Bohemia in August–September. On 22 December he defended his habilitation thesis Commentatio de examine physiologico organi visus et systematis cutanei. The study deals with such topics as accommodation, effects of color and intensity illumination, ability of the eye to follow moving objects, direct and indirect vision, and location of the optic nerve into the retina. In the opening sentences of his inaugural oration Purkyně declared his scientific worldview in modern terms: "The most important problem of a physician appears to me not his effort to renew a life already shattered, or to sustain a life a little longer, but efforts towards the support of evolving life; to protect it from harm; to bring it to the peak of perfection and beauty [..] The physician who assumes this task may be called an artist. Otherwise he merely performs the task of a repairman."[34] In 1824 he began supplying his lectures with demonstrations, so called experimental collegium; continued to research visual perception and published a two-volume follow-up to his dissertation in Berlin, subtitled Neue Beiträge zur Kenntniss des Sehens in subjectiver Hinsicht (1825), with dedication to Goethe.[35][36]

Purkyně intended to publish, in addition to his two Neue Beiträge, two other volumes dealing with the senses. The third volume was to contain additional material dealing with vision; the fourth volume was to deal with other senses. A substantial amount of the material was ready for publication. There were two reasons for delay. First, Tourtual published a volume on Human Senses with Reference to Mutual Relations of Psychological and Organic Processes (1827). Purkyně emphasized that Tourtual's approach to the study of visual phenomena was very close to his own. The second, and probably more important, reason was that Purkyně's interests shifted to the study of anatomical and microscopical issues.[37]

Professional affiliations

In 1824 he joined Filomatic Society where the Czech literature was often discussed.[38] That same year, he was accepted to Silesian Society for Patriotic Culture (Slezská vlastenecká společnost, Schlesische Gesellschaft für Vaterländische Kultur) where until 1850 he delivered over 60 reports about almost all of his works and inventions.[39]

In Summer 1826 he was accepted as an apprentice at a masonic lodge of Berlin which counted many influential physicians and civil servants among its members. He spent several months in Berlin. A year later he was appointed fellow and soon master.[40]

In October 1829 Purkyně was elected a member of Emperor Leopold Academy of Natural Sciences (Academia Caesarea Leopoldino-Carolina Naturae Curiosorum, today Leopoldina)[19], next year adopting name Darwin I. (in honor of Erasmus Darwin, grandfather of Charles Darwin).[41][42]

Working travels

In September 1826 he participated in the Congress of German Natural Scientists and Physicians in Dresden. He also took part in other editions: 18–23 September 1828 in Berlin where he met Ernst Heinrich Weber, Karl Ernst von Baer, Johannes Peter Müller, Anders Jahan Retzius and others; September 1833 in Breslau (visits of Retzius, R. Brown, Jan Svatopluk Presl, František Palacký); 18–23 September 1837 in Prague where he discussed with Jan Svatopluk Presl about the ways to transform the Prague Museum into Academy of Sciences.[43][44]

Julie Purkyně Rudolphi, before 1835, drawing. From Rozpravy Aventina, No 30, Vol 6 (1930-31), p 351 [6].
Family

He got closer to Karl Rudolphi's family, eventually marrying his daughter Julia Agnes Rudolphi (herself Protestant, born 1800) on 24 September 1827 (children: Rosalie, 10.2.1829–29.8.1832; Johanka, 1830–29.8.1832, both died of cholera; Emanuel, 17.12.1831–82, professor of natural sciences, botanist and meteorologist[20]; Karel, 11.3.1834–5.4.1868, painter [21]). Julie fell victim to a typhoid epidemic on 12 February 1835; he never remarried, but his house was always open to political exiles and impecunious scholars.[45][46]

Honors

In 1833 he received Montyon award in France for his monography De cellulis antherarum fibrosis nec non de granorum pollinarium formis commentatio phytotomica (1830).[47]

Political activism

In Breslau he founded Towarzystwo Literacko-Słowiańskie [Literary-Slav Society] (1836), and promoted national and political awareness.[48][49] In 1848 he participated in the Slavic Congress in Prague, for which he was criticised by journalists in Breslau.[50]

Ground plan of the Medical Faculty in Breslau. Physiological institute is at right (its southern part), near the church.
Breslau's Physiological Institute

In preparation since his early days in Breslau, and in 1836 approved by minister, in 1839 he founded the department of physiology (first in central Europe) in a newly reconstructed shed in the garden of the Academy on Katerina Street (opened on 8 November), since 1842 known as the Physiological Institute.[51][52]

Poetry translations

In 1841 he published two volumes of translations of Schiller's poems to the general acclaim in Breslau, however criticised in Prague (Karel Havlíček). He also collaborated on Polish translation of Ohlasu písní českých by František Ladislav Čelakovský, and wrote for magazines about the Russian literature.[53]

[edit] Second Prague period (1850–69)

Purkyně's study room in Prague.

In 1849, after initiative of Minister of Education Lev Thun-Hohenstein, Purkyně was appointed professor of physiology at the Prague Medical Faculty (emperor passing a decree on 4 November). He returned permanently to Prague on 9 April 1850. Back there, he was eagerly engaging in national enlightenment (lecturing in Czech already between 1850–53), cultural and organizatory activities. Until his last days he remained appreciated and admired by the public, and restlessly active. He began lecturing in April 1850.[54][55]

Physiological institute in Prague. It included an auditorium, section lounge, chemical laboratory, microscopic study room, physical cabinet, and room for collections. [7]
Prague's Physiological Institute

As soon as in 1851 he founded the Prague's physiological institute. Although his proposed locations were Klementium and Franciscan monastery on Jungmann Square, the institute found its home in a private apartment in the first floor of house no. 74 in Spálená street. Purkyně opened it on 6 October with the words: "Life entered into the world of inorganic things in order to follow Nature's laws not to disturb them." The talk was concerned the relation of physiology to sciences and arts and the methods of its theoretical and practical study.[56][57] He himself moved to the second floor in the house.[58]

Živa

Purkyně was named chairman of the Natural Sciences Committee of Czech Museum at its foundational meeting in October 1852. There he also proposed to start publishing a Czech magazine on natural sciences with its first issue appearing already in January 1853 under the name Živa, edited by Purkyně and the geologist Jan Krejčí, and published until today [22] (despite pauses between 1864–67, 1868–91 and 1915–53). Although the committee stopped functioning in 1858 its legacy was taken over by Živa, which also became publishing platform for young natural scientists from Purkyně's Physiological Institute.[59]

Representative positions

Between 1852–58 he was curator of the Committee for Education in Language and Literature of Matice česká. In 1854 he was appointed director of Královská česká společnost nauk [Royal Czech Society of Sciences]. Later he was named director (1857–59) of the first Czech industrial school he helped to found. He was named chairman of the Society of Czech Doctors at its foundational meeting in July 1862, with Purkyně using it as his main platform for struggle for reintroduction of Czech language in the Medical Faculty. In 1863 he was named vice-chairman of the newly founded Umělecká beseda; there he launched the Committee for natural-scientific research of Bohemia.[60]

Purkyně's closest social circle in Prague

Ladislav Čelakovský moved in to his house in 1852 after death of his father, a poet. In 1855, young botanist Julius Sachs moved from Breslau to Prague and stayed at his home while pursuing his studies; he later worked for Purkyně as his personal assistant and drawer, publishing a number of bonatical works in Živa [23]. Purkyně's assistants included Johann Nepomuk Czermak (1850–54; Jan Čermák; brother of painter Jaroslav Čermák; later professor of physiology at universities in Krakow and Leipzig; opened his own physiological institute in Prague in 1860), Eduard Grégr (1855–58) who was interested mostly in comparative physiology and anthropology, and Antonín Frič (1861–63).[61]

Purkyně's home served as a refuge meeting place of the Czech artists (esp. since 1857); he was a friend of poets Vítězslav Hálek, Jan Neruda and Pavel Jozef Šafárik, writers Božena Němcová and Karolina Světlá, painters Jaroslav Čermák, Mánes brothers and Maixner brothers, and philantropist Vojtěch Náprstek among others.[24] His friendship with many influential Austrian aristocrats stood him in good stead and the Austrian police authorities were never quite certain whether he was a dangerous " subversive element" or, according to a later assessment in his secret dossier, "an eccentric humanist who does not constitute a danger to State interests."[62] However in 1857 he got under police surveillance and was forced to quit his membership in the masonic lodge of Berlin.[63]

Working travels

In July 1856 he visited the World Exposition in Paris, met M. J. P. Flourens and Jaroslav Čermák who painted his portrait.[64] After being named a member of the Academy of Sciences in Vienna (1860) he regularly took part at its meetings (30 May 1861, June 1864, c20 May 1866). He also visited Vienna on other occassions (13.5.1856, 26.5.1859, 25.5.1865, 27.5.1867). In 1865 he participated in the Congress of Hungarian Doctors and Natural Scientists in Pressburg (today Bratislava, 29 August–2 September).[65]

Political activities

In March 1861 Purkyně was elected a member of the Czech Landtag (Český zemský sněm, Böhmische Landtag) in Slánsko, Velvary and Libochovice county. In his speech delivered on 11 April he demanded freedom of speech and freedom of press. His mandate ended on 21 December 1866. In 1867 he published political fable Austria polyglotta with his proposal for solution of national question in the Austrian monarchy following the Austro-Hungarian Compromise.[66][67]

Biotypological study of the faces of Purkyně, 1869, CDVs.[8]

[edit] Death and legacy

Purkyně died in 1869 in Prague after a long illness, and was buried in the Czech National Cemetery in Vyšehrad, Prague.[25]

Živa: Magazine for Popularization of Biology he founded in 1853 is published up to this date, by the Czech Academy of Sciences.[26] The issue 5/2011 was dedicated to his work (in Czech, available online).

The university in Ústí nad Labem is named after him (since 1991) and counts the Faculty of Art and Design (since 1993).

His contribution to the arts was discussed at the Excavating the Future: An Archeology and Future of Moving Pictures event initiated by Jaroslav Anděl in Prague (2001), and in the studies by Anděla Horová (1989)[68] and Lada Hubatová-Vacková (in Czech, 2005)[69]. Roman Prahl organised the exhibition "Jan Evangelista Purkyně a výtvarné umění" [Jan Evangelista Purkyně and Fine Arts] at the Convent of St Agnes of Bohemia in Prague in 1987.

[edit] Work

Purkyně contributed mainly to physiology, morphology, and psychology, but as well to anthropology (e.g. by constructing goniometer), botany, and zoology.

[edit] Sound figures, synaesthesia (1808–23)

Sound figures, from Purkyně's letter to Goethe, 1823.

As a philosophy student in Prague, Purkyně studied Ernst Chladni's sound figures (Klangfiguren; tonal vibrations visible in fine sand, which also triggered the interest of Goethe, Philip Otto Runge and Caspar David Friedrich), working on refining (using black mercuric sulfide, fixating it with copal varnish) and expanding Chladni's findings (he also kept personal contact with him). He discovered similar structures in his microscopic studies of the eye, and discussed them in his Dissertation (1819):

"The patterns appearing within the eye that I have described constantly bring back the memory of Chladni’s sound figures and especially the primary figures. I distinguish between the primary and secondary forms of Chladni’s figures. The primary patterns are generated by the moving parts of a sounding body, the secondary by the parts that remain at rest. It was the latter figures with which Chladni was principally concerned.

The primary sound patterns appear clearly when we place a layer of liquid on a horizontally held glass plate and then generate a tone by the stroke of a bow. Places that remain at rest in experiments with sand become covered alternately with beautiful raised and lowered forms of rectangular waves; they are smaller or larger depending on the height or depth of the tone, move toward one another in different directions, and create secondary figures at their boundaries where the liquid accumulates; in experiments with sand those grains ejected from the empty transparent spaces accumulate there.

This is an indispensable supplement to Chladni’s experiments, and it actually brings us to the basis of the tones. Although Chladni’s experiments with sand principally demonstrate the secondary lines, this experiment exposes the primary lines and suggests the origin of the secondary lines themselves. The experiment with the fluid becomes striking and exceptionally beautiful when we are able to generate particularly high tones. Then the whole surface teems with incredibly small squares that by the mutual boundaries between them create numerous and highly variable secondary lines. [..] The phenomenon becomes even more complex when several higher and lower tones sound simultaneously. Then greater and smaller waves run through each other in great diversity. These phenomena could be pursued further by measuring the tone waves, finding out their laws, studying the tones in more detail, and applying them to the physiology of hearing; they could be the topic of extensive treatises. I have touched on the subject only incidentally, in order to point out the analogy with visual patterns.

After I have observed the tone waves many times, my active fantasy repeatedly attempted to relate them to other natural phenomena. Soon the world of tones did not appear to me in its deep darkness, but it was accompanied by delicate formations generated instantly by changeable waves, which arose quickly before my inner eye and quickly disappeared, exerting a lovely vegetation to the moving sea of air. What is lacking, I thought, is that these tone images are not related to the phenomena of vision in all their beauty. Only somewhat higher sensitivity to light, and tones will float in a multitude of forms before our eyes; because it is surely unquestionable that where so many oscillations, mutual contractions and expansions of a fluid exist, warmth and light, which always accompany each other, should also exist.

On the other hand, I endeavored to explain the visual patterns in different ways. I reduced the dry crystalline lens to fibers; observed the cells of a frozen vitreous body; microscopically examined the retina and the globules of its core. However, nowhere did I find explanation for the phenomena I have observed.

Finally I was struck by the similarity of the visual patterns of squares and the tone waves, and I tend to believe that both phenomena have identical objective grounds.

In general, where opposite, continually interacting forces limit one another, there arises an alternating victory of one force over the other with a temporal periodicity and spatial oscillation; the first one dominates the other at different times, the second dominates the other one at different places, so that in the apparent external peace there can occur substantial movement within and between the terminal points.

Thus, as this actually occurs during acoustic movement, so it appears to me to be probable that the eye, whether it is under pressure from the outside or contracted by its own force, enters into inner oscillation that lasts as long as the contraction; the contraction occurs to a different degree in all eye structures depending on their elasticity."[70]
Purkinje images. The reflections of a candle flame from the structures of the eye. From Commentatio de examine physiologico organi visus et systematis cutanei, 1823, p 59.[9]. "Fig. 1. Candlelight reflection from anterior and posterior cornea and from the anterior and posterior portion of the lens. Fig. 2. Candlelight reflection from the anterior surface of the cornea and the posterior surface of the lens where the image is reversed. Fig. 3. Candlelight reflection from the anterior surface of the cornea and from the anterior surface of the lens where the reflection is erect. Fig. 4. Semicircular umbrula (weak shadow) which projects from the iris to the anterior surface of the lens. Fig. 5. A light from the substantia albuginea to the center of the anterior chamber."[71]

Purkyně later discussed these experiments in his letter to Goethe in 1823.[72] In addition to the detailed description and drawings, Purkyně sent him a wooden box with small glass plates, with record of his attempts to visualise the phenomenon of acoustic waves (plates and letter are both stored in the collections of Stiftung der Weimar Klassik, inv. no. GNP 538). Purkyně found visual analogies between microscopis physiology of organism and suprapersonal physical laws. Goethe considered these figures for some kind of natural hieroglyphs which are the carriers of universal harmony.[73]

Purkyně also dealt with the interconnectedness of the senses from a different perspective. In his Wrocław lectures in 1830s he examined the unity of sensations and interdependence of sensory organs. He studied how one sense can replace another in case of its failure, e.g. whether hearing can simulate vision with closed eyes (or in case of sudden blindness; called "cross wiring" or "cross activiation" by neuropsychologists today); he dealt with the emergence of phantom visual imagination and spatial orientation when perception is limited to audible echoes (coming from various remote locations). He also researched methods for capturing phenomena at the borderline of merging perceptions through different senses.[74]

Sight galvanic light patterns [Die galvanische Lichterscheiung, Lichtfigur], in Neue Beiträge zur Kenntniss des Sehens in subjectiver Hinsich, 1825, p 54.[10]

[edit] Visual perception (1818–25)

Later, as a medic, Purkyně studied various subjective visual phenomena, including pressure, light-shade, galvanic and vascular patterns (branching blood vessels in his own eye); patterns emerging from glare; feelings in the dark (phosphenes); representations of blind spots; unity of the visual fields of both eyes; double vision; indirect vision; color blindness of peripheral parts of the retina; Purkinje effect (sometimes called "Purkinje shift", change in the relative luminosity of colors when eye is adapting to the darkness; e.g. when light intensity decreases, red objects seems to fade faster than blue objects of the same brightness; discussed in Chapter 10 of his Neue Beiträge)[27]; light tracks; and afterimages [Nachbilder, paobrazy].

In his research of afterimages, Purkyně continued Goethe's work on their persistence and modulation: how long they lasted, what changes they went through, and under what conditions. His empirical research and Johann Friedrich Herbart's mathematical methods were to come together in the next generation of psychologists and psychophysicists, when the threshold between the physiological and the mental became one of the primary objects of scientific practice. Instead of recording afterimages in terms of the lived time of the body as Goethe had generally done, Purkyně was the first to study them as part of a comprehensive quantification of the irritability of the eye. He provided the first formal classification of different types of afterimages and his drawings of them are a striking indication of the paradoxical objectivity of the phenomena of subjective vision. Although working with relatively imprecise instruments, Purkyně timed how long it takes the eye to become fatigued, how long dilation and contraction of the pupil take, and measured the strength of eye movements. For him the physical surface of the eye itself became a field of statistical information: he demarcated the retina in terms of how color changes hue depending on where it strikes the eye, describing the extent of the area of visibility, and quantified the distinction between direct and indirect vision, and also gave a highly precise account of the blind spot. Purkyně's research, along with that of Johannes Peter Müller and others, inaugurated the comprehensive physiology of vision in the 19th century.[75]

[edit] Method for objective investigation of the eye (1823)

He proposed a method for continuous objective investigation of the eye, which is noteworthy particularly for its use of reflective images. The candle flame (or other object) is reflected from the structure of the eye four times: on the outer and inner surfaces of the cornea, and on the anterior and posterior surface of the lens. Purkyně highlighted the use of these reflective images (today known as Purkinje-Sanson images, or Purkinje reflexes, or catoptric images) to measure the curvature of the cornea (the principle of keratometry and ophthalmometry)[28] and their further use for diagnostics of diseases and disorders of the eye; described his observation of the frontal segment of the eye in an oblique focal illumination and by biomicroscopy of the eye (later Gullstrand principle); and observed fluorescence of the eye and came up with the method of observing the back of the eye in vivo, which later served as the principle of ophthalmoscopy established in 1850 by Hermann von Helmholtz.[29]

From Commentatio de examine physiologico organi visus et systematis cutanei, 1823, p 59.[11]

[edit] Investigation of the skin surface (1823)

Purkyně published a thesis that recognised 9 principal configuration groups of fingerprints (in the late 19th century Francis Galton used these patterns as the basis of a fingerprint classification system that could identify specific individuals); also observing the skin capillaries in vivo.

[edit] Physiological practice (1823)

Purkyně stressed the importance of the constitution in medicine, which is also related to differences among healthy individuals, and the need for individualization in the examination and assessment of patients. He also pointed to the importance and need for preventive aspects in medicine and the role of physiology in maintaining health care.

[edit] Studies of hearing (1824–62)

Combination tones (so called Tartini's third tones, 1824) are of subjective origin; the possibility of locating the amplitude of the vibrating plate by auscultation with a special tool (predecessor of the stethoscope, 1825). Later he was interested in locating the direction of the sound, the bone conduction, use of hearing aids to amplify sound for people experiencing hard-of-hearing (1859–62). These studies were well received.

[edit] Physiology of human speech (1827–65)

Differentiation between phonation organs (larynx) and resonant spaces; attempt to sort phones in terms of articulation and acoustics; use of the acquired knowledge to improve speech and correcting its defects. Early work in the field of phonetics, German manuscript was lost in the Berlin Academy, discovered only in 1960.

Phorolyt. [12]
Kinesiscopic disc with the portraits of Purkyně, 1865.[13] He would use this disc to entertain his grandchildren by showing them how he, an old and famous professor, is turning around at great speed.[76]
Kinesiscopic disc. Photo: Petr Kliment. [14]

[edit] Perception of space and movement, photomicrography (1827–53)

Purkyně distinguished between subjective and objective visual space (1827, 1837). Investigated spatial perception using other senses (1840, 1853).

He pioneered the use of photomicrography to aid the examination of microscopic samples. In 1840 he improved upon the phenakistoscope of Joseph Plateau and the stroboscopic disc of Simon von Stampfer by placing the pictures and the slots onto two separates disks mounted on the same axis. Purkyně's first machine was named Phorolyt (forolyt) and was marketed in Breslau in two sizes as a scientific toy. Later in the 1840s, he replaced the drawings with three-dimensional figures, a technique he referred to as phorografia. He further developed the Phorolyt, re-naming it the Kinesiscope (kinesiskop, pohybohled).[30] A disc would hold nine posed photographs of an object in movement intended for projection when Kinesiscope viewer was attached to a magic lantern. He described such created illusion of movement as being based on the principle of alteration of seen image and afterimage (1865)[77]. Kinesiscope discs were used in his lectures throughout the decade (one survives at the Technical Museum, Prague). In 1865, Purkyně traveled with this apparatus to the Congress of Hungarian Doctors and Natural Scientists in Pressburg (today Bratislava), and used it to demonstrate the action of the human heart and the circulation of blood. He described Kinesiscope in Riegrův slovník naučný[78]:

"Kinesiscope, is a word from Greek for the instrument of physiology and physics by which various movements of natural as well as artistic objects can be represented. That is to say every movement is becoming in a sequence of time, in every moment of this time the object occupies a certain spatial position which changes while making transition into the next moment. These changes represent themselves on a moving plane in a sequence, when this plane then moves either in a circular or linear way so that individual pictures occupy the same position in a highest speed and stop for a moment there, the eye conceive them as if on the same spot changing in time. In this way, one can achieve that even movements of all kinds can be represented. To achieve this goal, there are various means used, simple or more elaborated according to how this branch has evolved with time. [..] it is especially important that the most diverse movements of natural, historical, and artistic performances can be presented even to a wider public, and a special branch of scientific industry will emerge from this, useful in schools and, in general, for education and entertainment. For instance, in the field of physics, it is possible to present various kinds of the wave motion of liquids, sound, and light, the most complex machines in their motion; in the field of physiology, the motion of the heart, the blood circulation, the nerve currents, the muscle activity; in natural history, the movement of various animals on the ground and in the air, the most diverse play of colors, physiognomic expressions on the human face, dramatic motions, the growth of plants and other organic bodies, figurative representation from all sides, which otherwise is not possible to execute on a simple plane; in the field of history, the performances of various groupings of human action, for instance, battles, balls, marches and others. These performances can take place either on a smaller scale or in any enlargement on transparent surfaces. It can be expected that thanks to the mastery of artists this thing will become in time a special branch of fine arts, in which it will not suffice to create only a single moment of the evolving act, but also a complete story and complete narrative."[79][31]

[edit] Other research

Vertigo - body posture - maintaining balance (1820–27); The consequences of experimental brain and cerebellum injury (1824–26); Drug testing - physiological pharmacology (1820–29); Development of the chicken egg before hatching (1825–30); Plant structures (1828–30); Microscopic composition of animal tissues (when after seven-years war with the authorities he was allowed to buy a "large" achromatic Plössl microscope[80], 1832–45), including discovery of Purkinje cells (large neurons with many branching dendrites found in the cerebellum, 1837), making him the co-founder of cell biology, and Purkinje fibres (the fibrous tissue that conducts electrical impulses from the atrioventricular node to all parts of the ventricles of the heart, 1839); Embryology (1825–37); Ciliary movement (1833–36); Digestion in vitro (1835–37); Functional morphology (1839–45); Physiological basis of sleep and wakefulness (1846–49).

[edit] Notes

  1. Franta 2011, p. 198
  2. Kruta 1985
  3. WadeBrožek 2001, p. 27
  4. WadeBrožek 2001, p. 27
  5. Franta 2011, p. 198
  6. WadeBrožek 2001, p. 27
  7. Franta 2011, p. 198
  8. WadeBrožek 2001, pp. 27-28
  9. Franta 2011, p. 198
  10. Rieger 1867, p. 1115
  11. Rieger 1867, p. 1115
  12. WadeBrožek 2001, p. 28
  13. Franta 2011, p. 198
  14. WadeBrožek 2001, pp. 28-29
  15. Franta 2011, p. 198
  16. Kruta 1985
  17. WadeBrožek 2001, p. 29
  18. WadeBrožek 2001, p. 29
  19. Franta 2011, p. 198
  20. Kruta 1985
  21. WadeBrožek 2001, p. 29
  22. Hubatová-Vacková 2005, p. 8
  23. Franta 2011, p. 198
  24. Kruta 1985
  25. Franta 2011, p. 198
  26. Goethe 1824
  27. WadeBrožek 2001, p. 110
  28. Posner 1969, p. 107
  29. Franta 2011, p. 198
  30. Kruta 1985
  31. Posner 1969, p. 107
  32. Franta 2011, p. 198
  33. Kruta 1985
  34. Posner 1969, pp. 107-108
  35. Franta 2011, pp. 198-9
  36. Kruta 1985
  37. WadeBrožek 2001, p. 32
  38. Franta 2011, pp. 198-9
  39. Kruta 1985
  40. Franta 2011, p. 199
  41. Franta 2011, p. 199
  42. Kruta 1985
  43. Kruta 1985
  44. Franta 2011, p. 199
  45. Franta 2011, p. 199
  46. Kruta 1985
  47. Franta 2011, p. 199
  48. Franta 2011, p. 199
  49. Kruta 1985
  50. Franta 2011, p. 199
  51. Franta 2011, p. 199
  52. Kruta 1985
  53. Franta 2011, p. 199
  54. Franta 2011, p. 199
  55. Kruta 1985
  56. Posner 1969, p. 109
  57. WadeBrožek 2001, p. 33
  58. Franta 2011, p. 199
  59. Franta 2011, p. 199
  60. Franta 2011, p. 199
  61. Franta 2011, p. 199
  62. Posner 1969, p. 109
  63. Franta 2011, p. 199
  64. Kruta 1985
  65. Kruta 1985
  66. Franta 2011, p. 199
  67. Kruta 1985
  68. Horová 1989
  69. Hubatová-Vacková 2005
  70. WadeBrožek 2001, pp. 70-71
  71. John 1959, p. 61
  72. SkramlikKopecký 1956
  73. Hubatová-Vacková 2005, pp. 26-28
  74. Hubatová-Vacková 2005, pp. 28–30
  75. Crary 1988, pp. 13–14
  76. Hubatová-Vacková 2005, pp. 12-13
  77. Hubatová-Vacková 2005, pp. 12-13
  78. Purkyně 1865
  79. Purkyně 1865
  80. Posner 1969, p. 108

[edit] Literature

Writings by Purkyně
Purkyně's Dissertation, 1819. (in German) View online.
Published by Purkyně
Writings on Purkyně
Nicholas J. Wade, Josef Brožek: Purkinje's Vision: The Dawning of Neuroscience, 2001. Includes English translation of Purkyně's dissertation. Download PDF.
Živa: Special Issue on J. E. Purkyně, No. 5, 2011. (in Czech) View online.
  • Goethe, Johann Wolfgang von (1824). "Das Sehen in subjectiven Hinsicht, von Purkinje, 1819". Zur Naturwissenschaft überhaupt, besonders zur Morphologie, Bd. 2, Heft 2. Stuttgart/Tübingen: Cotta. pp. 102–177 (German). Goethe's commentary on Purkyně's Dissertation.
  • "Jan Purkyně", Světozor, Vol 1, Nos 17-18, 20, 22 (1867). (in Czech) [48] [49] [50] [51] [52]
  • Rieger, Frant. Lad., ed. (1867). "Jan Evangelista Purkinje". Riegrův slovník naučný, Vol. 6: P - Quousque tandem. Prague: I. L. Kober. pp. 1115–1119 (Czech).
  • Emanuel Rádl, Jana Ev. Purkyně práce histologické, Prague: Král. čes. společ. nauk, 1900, 51 pp. (in Czech)
  • Ethel Mary Chamberlain, A Study of the Purkinje phenomenon with spectral lights, University of Chicago, 1911. Dissertation.
  • Karel Amerling, Jan Evangelista Purkyně: badatel, reformátor a buditel, Prague: F. Topič, 1918, 73 pp. (in Czech) [53]
  • Karel Chodounský, Jan Evang. Purkyně: Působení jeho pro rozvoj české kultury, Prague: Č ak. věd a umění, 1927, 180 pp. (in Czech)
  • Růžena Pokorná-Purkyňová, "U Purkyňů před sto lety", Rozpravy Aventina, 1931, Vol. 6, No. 30, p 350.
  • Johannes Urzidil, Goethe und J.E. Purkyně. Teil 1, Prague, 1937, 443 pp. (in German)
  • Jarmila Psotníčková, Rodokmen J.E. Purkyně, Prague: Purkyňova společnost, 1937, 24 pp. (in Czech)
  • Franz Krause, Weg und Welt des Goetheanisten Johannes Evangelista Purkyně (in German). Trans. Goethovec Jan Evangelista Purkyně, Prague: Anthroposofická společnost v republice Československé, 1937, 31 pp. (in Czech)
  • Miloslav Matoušek, Jan Evangelista Purkyně: životopisný nástin, Prague, 1937, 23 pp. (in Czech)
  • Růžena Pokorná-Purkyňová, Život tří generací, Prague, 1944. Commented correspondece of Purkyně family. (in Czech)
  • Miloslav Matoušek, Život Jana Evangelisty Purkyně, Prague: Práce, 1946, 81 pp. (in Czech)
  • Mikuláš Teich, Jan Evangelista Purkyně, Brno: Rovnost, 1950, 25 pp. (in Czech)
  • R. Skopec, "Jan Evangelista Purkyně a fotografie", Nová fotografie, No 11, 1952, p 122. (in Czech)
  • Oldřich Vilém Hykeš, J.Ev. Purkyně: 1787-1869, Prague: Orbis / Naše věda, technika, umění a jejich představitelé (materiál k nástěnkám), 1953, 7 pp. (in Czech)
  • J. Brichta, "Purkyňův přínos k vynálezu kinematografie", Vesmír, 1953, pp 250-253. (in Czech)
  • R. Skopec, "Jan Evangelista Purkyně a fotografie", ČsF, No 9, 1955, p 102. (in Czech)
  • Otakar Matoušek, Bohumil Němec (eds.), Jan Evangelista Purkyně: Badatel - národní buditel: Soubor příspěvků o jeho životě a práci, Prague: Čs. akademie věd, 1955, 250 pp. (in Czech)
  • Jarmila Psotníčková, Jan Evangelista Purkyně: Soubor obrazů a dokumentů, Prague: Orbis / Obrazové publikace, 1955, 47 pp. (in Czech)
  • Eva Rozsívalová, Život a dílo J.E. Purkyně, Prague: ČSAV, 1956, 144 pp. (in Czech)
  • Skramlik, Emil v.; Kopecký, M. (1956). "Purkyňův pokus o analysu zvuku". Československá fysiologie 5 (4): 401-406 (Czech).
  • John, H.J. (1959). Jan Evangelista Purkyně: Czech Scientist and Patriot 1787–1869. Philadelphia, PA: American Philosophical Society.
  • O. Matousek, "J.E.Purkyněs Leben und Tätigkeit im Lichte der Berliner und Prager Archive", Nova Acta Leopoldina, 24 (1961), pp 109–129. (in German)
  • Vladislav Kruta, Jan Evangelista Purkyně, Prague: SZdN, 1962, 127/143/143/142/142/147 pp. (in Czech, English, German, French, Spanish, Russian)
  • Olga Macková (ed.), Karel Purkyně 1834-1868: Souborná výstava díla, Prague: National Gallery, 1962, 50 pp.
  • Vladislav Kruta, K počátkům vědecké dráhy J.E. Purkyně: Korespondence s přáteli z pražských let 1815-1823, Prague: SPN / Sborník prací lék. fak. v Brně, 1964, 207 pp. (in Czech)
  • Vladislav Kruta, "Goethovy a Purkyňovy studie vidění", Zprávy čs. společnosti pro dějiny věd a techniky, 3, 1966, pp 30-35. (in Czech)
  • Vladimír Smetana, Jan Evangelista Purkyně 1787-1967, Prague: Encyklopedický institut ČSAV, 1967, 27 pp. (in Czech)
  • Vladislav Kruta, The Poet and the Scientist: Johann Wolfgang Goethe - Jan Evangelista Purkyně, Prague: Academia, 1968, 44/46 pp. (in English, Czech)
  • Vladislav Kruta, J.E. Purkyně (1787-1869) Physiologist: A Short Account of his Contributions to the Progress of Physiology with a Bibliography of his Works, Prague: Academia, 1969, 137 pp.
  • Posner, E. (1969). "J. Evangelista Purkyně (1787-1869)". British Medical Journal (3): 107-109.
  • Vladimir Kruta (ed.), Jan Evangelista Purkyně 1787–1869. Centenary symposium, Brno: Universita Jana Evangelisty Purkyně, 1971. (in Czech)
  • Václav Spěváček, J.E. Purkyně a západní Čechy, Pilsen: Západočes. nakl, 1972, 109 pp.
  • Ivan Kubišta, Purkyně ve Vratislavi, 3rd edition, 1974, Prague: Mladá fronta, 335 pp. (in Czech)
  • Kruta, Vladislav, ed. (1985). Jan Evangelista Purkyně: Sebrané spisy, Vol. XIII. Prague: Academia (Czech). [54]
  • E. Trávníčková (ed.), Jan Evangelista Purkyně. Život a dílo, Prague: Avicenum, 1986. (in Czech)
  • Josef Brožek, Jiří Hoskovec, J. E. Purkyně and Psychology: With a Focus on Unpublished Manuscripts, Prague: Academia, 1987, 137 pp.
  • Libochovice - město Jana Evangelisty Purkyně: sborník vydaný k 200. výročí narození velkého českého vědce a buditele, Libochovice: Městský národní výbor, 1987, 36 pp. (in Czech)
  • Václav Žáček, Jan Evangelista Purkyně, Melantrich, 1987, 363 pp. (in Czech)
  • Josef Haubelt, Jan Evangelista Purkyně, Prague: Horizont, 1987, 139 pp. (in Czech)
  • Jana Jakrlová, Josef Sajner, "J.E. Purkyně jako ilustrátor vlastních vědeckých prací", Vesmír 7, 1987, pp 379-382. (in Czech)
  • Crary, Jonathan (1988). "Techniques of the Observer". October (The MIT Press) 45 (Summer): 3-35.
  • Horová, Anděla (1989). "Jan Evangelista Purkyně a dějiny výtvarného umění". Estetika 26 (1): 116-121 (Czech).; English trans. in Jan Evangelista Purkyně in Science and Culture, 1988, pp 197-209.
  • Jaroslav Purš (ed.), Jan Evangelista Purkyně in Science and Culture: Scientific conference, Prague, August 26-30, 1987, Prague: Ústav československých a svĕtových dějin Československé akademie věd, 1988. 2 volumes. (in English, Czech, Russian)
  • J. Kröhn, "Purkyňův kinesiskop", Věda, technika a my, No 7, 1994, p 7. (in Czech)
  • Wade, Nicholas J.; Brožek, Josef (2001). Purkinje's Vision: The Dawning of Neuroscience. Mahwah, NJ: Lawrence Erlbaum Associates. Includes English translation of Purkyně's dissertation.
  • Stezka Jana Evangelisty Purkyně, Moravský Beroun: Moravská expedice / Do nitra Askiburgionu, 2003, 118 pp. (in Czech)
  • Hubatová-Vacková, Lada (2005). Vnitřní zrak: Jan Evangelista Purkyně, laboratoř vizuality a moderní umění. Prague: Centre for Theoretical Studies (Czech). A version was published in Umění/Art, No. 6, Vol. 53 (2005), pp 566-585, PDF.
  • Siegfried Zielinski, "Electrification, Tele-Writing, Seeing Close Up: Johann Wilhelm Ritter, Joseph Chudy, and Jan Evangelista Purkyně", in Deep Time of the Media: Toward an Archaeology of Hearing and Seeing by Technical Means, MIT Press, 2006, pp 159-204.
  • Živa: Special Issue on J. E. Purkyně, No. 5, 2011. ISSN 0044-4812. (in Czech)
  • Irina Melnik, Jan Evangelista Purkyně: životopisný komiks k výstavě Národního muzea Vynálezci a vynálezy konané od 27.9.2011 do 1.5.2012, Prague: National Museum, 2011, 12 pp. (in Czech) Exhibition
Films on Purkyně
  • Jan Evangelista Purkyně, TV documentary, dir. Václav Sklenář, 1987, 23 min. [55]
Radio programs on Purkyně

[edit] External links

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