Body Modern: Fritz Kahn, Scientific Illustration, and the Homuncular Subject by Michael Sappol (review)

Fritz Kahn (1888–1968), a graduate of the Berlin medical school, became a visual popularizer of medicine and science. He became famous for depicting the human body as an industrial machine. Using highly innovative visual metaphors and similes (see an example at https://www.nlm.nih.gov/dreamanatomy/da_g_IV-A-01.html), Kahn's homunculus "body-machines" appeared in dozens of books reaching print runs of more than ten thousand. They are paradigmatic examples of what Sappol calls "conceptual scientific illustration" (p. 1), which is defined as illustrations intending to represent function, not appearance. The approximately fifty black-and-white figures interspersed in the text together with fourteen color plates represent the enormous breadth of Kahn's images very well, and the author's lucid commentaries provide excellent guidance through the forest of Kahn's topics, ranging from anatomy to architecture, and from physiology to thermodynamics. In chapter 4—to me the best in the book—Sappol provides a "variety show" of the various visual devices, motifs, and techniques used by Kahn and his team of at least twenty-five illustrators who put his ideas onto paper and produced the final images. About many of them little is known, and readers interested in their practical work and techniques and in their biographies are advised to turn to Miriam Eilers's unpublished historical dissertation, "Lebensbild(er) von Fritz Kahn," which is also heavily cited by Sappol, and to her 2016 medical dissertation, "Genesis and reception of popular knowledge in the Weimar Republic," which is available online.¹ However, each of his figures clearly identifies all known illustrators, which is already an improvement over many texts on Kahn mistaken himself as the executing artist. Sappol convincingly places Kahn's oeuvre in the context of trends in modern art such as Dada, art deco, and the Bauhaus, progressive reform education, and the pictured knowledge movement. Surrealism is substantially undervalued in his account, and the fine line between popular science and pseudo-science is not kept sufficiently in view. Sappol overstresses the American origins of this style of illustration (e.g., p. xi), since Kahn wrote his Ph.D. thesis in Germany in 1912 and published his first popular books there (e.g., Das Leben des Menschen, 1922–31, with the iconic inserted poster Der Mensch als Industriepalast in vol. 3, 1926). Only later did he become famous in the United States, where he, the son of a Jewish physician, fled after the Nazi seizure of power in 1933. Thus for an understanding of Kahn's visuality, more important than the Popular Science Monthly are the Berliner Illustrierte Zeitung, the Uhu, and the heavily illustrated books of the popular science publisher Franck in Stuttgart (where Kahn also published his first books). In chapter 5, we learn more about his later impact on the "iconophilic diaspora" (p. 133) of Jewish émigrés in New York, but we also learn that even Nazi illustrators in Germany took over many of his innovative techniques, of course without any due acknowledgment.

What I found a bit disturbing in the book is its postmodern style (e.g., in chap. 1 and 6), and the far too frequent invocation of "modernity" (pp. 5ff.) as the driving force behind Kahn's endeavors: modernity is not in itself his goal, but the end result of other motifs, such as strong impact or clarity of the message, free from superficial or wordy packaging and visual ornamentation. Altogether I can recommend this book to all historians of modern science and medicine, and to students of the visual culture of functional scientific illustration as a thorough exegesis of Kahn's imagery and its broader impact.