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Salomonsen, Carl Julius


(b. Copenhagen, Denmark, 6 December 1847; d. Copenhagen, 14 November 1924)

medicine, bacteriology.

The only child of a wealthy and cultured family, Salomonsen obtained an excellent education in both the sciences and the classics. He was the son of Martin Salomonsen, a physician who had published scientific works on epidemiologic problems, and Eva Henriques, whose family included many eminent physicians in Denmark.

After undergraduate work at the Metropolitan school in Copenhagen, Salomonsen received the M.D. (1871) at the University of Copenhagen. He also took a great interest there in zoological studies, which later inspired his works in experimental pathology and parasitology. Through his father’s friendships with the archaeologist Worsaae and the physiologist Peter Panum, Salomonsen met Virchow and became his private secretary, assisting him in his Copenhagen measurements of ancient skulls (1869).

During his first years as a physician, Salomonsen shared a large practice with his father. He also worked as an assistant in the pathology department of the Almindelig Hospital and, later, at the Kommunehospital, where Fritz Valdemar Rasmussen and Panum inspired his interest in the relationship between bacteria, which had recently been discovered, and pyemic processes. Pasteur and Koch had published his investigations concerning the putrefaction of blood and the role of microbes in the fermentative effects of putrefaction.

In 1877 Salomonsen defended his thesis “Studier over Blodets Forraadnelse”–some opponents finding it a book more of botanical than of medical interest. Nevertheless, it became the fundamental starting. He showed that the colorshift in putrid blood at 5–10°C is produced by microbes that have begun to putrefy. With the aid of long capillary tubes he isolated live microbes and developed a method for growing them in pure cultures. (This method of cultivation was soon surpassed by Koch’s use of transparent solidifiable media.) In his thesis Salomonsen suggested dyeing bacteria in diluted fuchsine solutions to preserve the form of the more microbes better than was possible with the more complicated dyeing in hardened preparations. His thesis also gave effective support to the school of Ferdinand Cohn, who maintained that the bacteria were distinct species, against the school of Billroth, who considered them different forms of a single species of coccobacteria septica.

After defending his thesis, Salomonsen traveled to Germany and Paris for half a year. In Breslau (now Wroclaw) he worked with Julius Cohnheim; and together they demonstrated the specificity of tuberculosis. That was in 1878, four years before Koch’s discovery of the tubercle bacillus. They used an aseptic method of inoculating fresh tuberculous material into the camera anterior bulbi of rabbits. In Breslau Salomonsen also met many scientists, including Weigert Welch, Neisser, Koch, and Ehrlich. In Paris he met Pasteur–an encounter that later proved of great significance for young Danish bacteriologists. On his return to Copenhagen, Salomonsen was appointed prosector at the Copenhagen Municipal Hospital. He also lectured privately, and thus began his lifelong interest in education.

In 1878 Salomonsen published “Notits om Forekomsten af Bakterier i metaVstatiske Pusansamlinger hos Levende”, an investigation of bacteria from pus accumulations in live human beings. He identified streptococci from various suppurations and, by inoculating pyogenic material in rabbits, developed a fatal peritonitis with streptococci in pure cultivation.

In 1883 Salomonsen was named lecturer in medical bacteriology at Copenhagen. His was the first such chair in Europe. In the cellar of the Botanical Museum of Copenhagen he assembled a circle of physicians and veterinarians who diligently followed his demonstrations and lectures. Among this group were the physicians Vilhelm Jensen; Thorvald Madsen, later director of the State Serum Institute; J. Christmas; and the veterinary surgeons Bernhard Bang and C. O. Jensen. In 1885 Salomonsen published his important textbook Ledetraad i Bakteriologisk Teknik, which was translated into English, French, and Spanish.

In 1893 Salomonsen was named professor of pathology at the University of Copenhagen and for nearly two decades used the new chemistry and physiology laboratory facilities that had been installed in a building in Ny Vestergade. In 1910 he moved to the Rigshospital, where a special building had been constructed for him.

During these years, Salomonsen published his investigations on immunity (1880), diphtheria (1891), and anthrax (1899). In 1884 he published, with Christmas, his studies on pseudoinfection and the ophthalmia the ophthalmia produced by the jequirity. In this work he demonstrated that the jequirity microbe is nonvirulent; the venom promoted a morbid predisposition in test animals that enabled the microbes to develop in the blood, thus producing a pseudoinfection. When serum therapy was developed, Salomonsen quickly acknowledged both its practical and its scientific value: and in Ny Vestergade he built up a small department for the production of antidiphtheric serum. Because of the widespread use of this serum. both in hospitals and in research on immunity, the department soon sought better facilities, and Salomonsen proposed (1896, 1899) the construction of an independent serum institute. Despite political difficulties and economic restrictions, he succeeded with his plans and the institute was inaugurated in 1902. He had hoped to have it affiliated with the university, but it was taken over by the Ministry of Health. Denmark being a small country, the institute has been able to sponsor many centralized investigations on immunity serum reactions in infectious diseases. These surveys have made its research world famous.

Salomonsen was director of the State Serum Institute until 1909, when Madsen, his collaborator, succeeded him. They investigated antitoxin formation in horses that were diphtheria-immunized (1896) and demonstrated the fluctuating progress that led to studies of the basis of antitoxin formation. They showed that the cells of an organism that is actively immunized have the unique ability to produce antitoxins. They also observed a constant formation and destruction of such substances and identified the stability of the antitoxin quantity by bleeding the animals and replacing the evacuated blood with transfusions of fresh blood (1897). Because of his interest in hygienic problems, Salomonsen made certain that vaccination procedures in Denmark were reformed; only animal vaccine from healthy calves was used — human vaccine was prohibited.

With Georges Dreyer, Salomonsen demonstrated the physiological effects of radium on amoebas and trypanosomes. He also showed (1904), that radium produces severe hemolysis Besides his inspiring work as a bacteriologist, Salomonsen was interested in the improvement of education. In 1917 he proposed the construction of a tuition-free college for needy students—an idea that was realized shortly before his death. His many addresses on science, biography, university education, and the history of medicine were published in 1917.

Salomonsen was a cofounder (1907) of the Danish Museum for the History of Medicine and from 1917 president of the Danish Society for the History of Medicine. As dean of the University of Copenhagen, he published (1910) a historical essay on epidemiologic theories during the first half of the nineteenth century; and he wrote (1914) on the sanctuary of Asclepius on Cos. In 1921 he published a book of silhouettes of many outstanding scientists of his time, taken from his personal collection. He also published two polemics on dysmorphism in art, believing that art forms produced just after World War I reflected a deranged state of mind.

In 1891 Salomonsen was elected to the Royal Danish Academy of Sciences. He was made honorary doctor of medicine in 1905 by Victoria University of Manchester and in 1911 by the University of Christiania (Oslo). In 1880 he married Ellen Henriques. His last years were complicated by crippling rheumatoid arthritis and the death of his wife and only daughter.


I. Original Works. Salomonsen’s major works are Studier over Blodets Forraadnelse (Copenhagen, 1877), his M.D. diss.; “Notits om Forekomsten af Bakterier i metestatiske Pusansamlinger hos Levende”, in Nordiskt medicinskt archiv, 10 (1878), 1 – 10; “Versuche über künstliche Tuberculose”, in Jahresberichte der Schlesischen Gesellschaft für vaterländische Kuliur, 56 (1878), 222–223, written with J.Cohnheim; “Om Indpodining af Tuberculose i Kaniners Iris”, in Nordiskt medicinskt archiv, 11 , no. 12 (1879), 1 – 29, and no. 1 – 38; “Eine einfache Methode zur Reinkultur verschiedener Fäulniss bacterien”, in Botanische Zeitung, 38 (1880), 481–489; “Nyeste experimentelle Undersøgelser over Immunitet;”, in Hospitalstidende, 71 (1880), 861–872, 881–894; “Uber die Aetiologie des Jequerity-ophtalmie”, in Fortschritte der Medizin, 2 (1884), 78 – 87, written with J. Christmas: “Ueber Pseudo-Infektion bei Froöschen,” ibid., 617–631; Ledetaad for Medicinere i Bakteriologisk Teknik (Copenhagen, 1885); and Bakreriologisk Teknik for Medicinere (Copenhagen, 1889; 4th ed., 1906); with French trans, by R. Durand-Fardel, Technique élémentaire de bactériologique à I’usage des medecins (Paris, 1891), and English trans., Bacteriological Technology for Physicians (New York, 1891).

Later work include “Diterilaerens nuvaerende Standpunkt”, in Ugeskrift for Leager, 24 (1891), 63 – 79 “Redegørelse for Virksomheden ved den serumtherapeutiske Anstalt”, in Hospitalstidende, 4 , no. 1 (1896), 225 – 226 “Studier over Antitoxindannelse”, in Nordiskt medicinskt archiv, 30 (1897), 1–21, written with T. Madsen; “Forslag om Oprettelse af et Seruminstitut”, ibid., 7 , no. 4 (1899), 142; “The Rise and Growth of the State Serum Institute”, in the Festskrift ved Indvielsen of Statens Seruminstitut (Copenhagen, 1902), 1 – 20 “Recherches sur les effets physiologiques du radium”, in Comptes rendus hebdomadaires des séances de I’Académie des sciences, 138 (1904), 1543–1545, written with G.Dreyer:Erindringsord og Notesbog for Deltagere i de medicinskbakteriologiske Øvelser ved Københavns Universitet (Copenhagen, 1906: 2nd ed., 1911); and Epidemiologiske Teorier i den første Halvdel af det 19, Aarhundrede (Copenhagen, 1910).

See also Erindringsord og Notesbog for Deltagere i de experimental-pathologiske Øvelser ved Københavns Universitet (Copenhagen, 1912; 2nd ed., 1919); Menneskets Snyltere (Copenhagen, 1913), with atlas (1913); Asklepios’ Helligdom på Kos (Copenhagen, 1914); Maa-Arbejder (Copenhagen, 1917); Smitsomme Sindslidelser for og numed Henblik paa de nyeste Kunstretninger (Copenhagen, 1919); Om Dysmorfismens sygelige Natur (Copenhagen, 1920); and Medicinske Silhouetter (Copenhagen, 1921).

II.Secondary Literature. On Salomonsen and his work, see E. Gotfredsen,Medicinens Historie, 3rd ed. (Copenhagen, 1973), passim; T. Madsen, “Carl Julius Salomonsen”, in Oversigt over glet Kd Danske Videnskabernes Selskabs Forhandlinger (1925), 59 – 75 and Oluf Thomsen, “Carl Julius Salomonsen”, in Copenhagen University Program (Nov. 1925), 75–81.

E. Snorrason

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