The nearly life-sized poster titled Der Mensch als Industriepalast (Man as an Industrial Palace) depicts the human body as a complex machine, a wonder of the industrial age.

Workers stand at power plant-like control panels and operate the body’s central nervous and respiratory systems. Oxygen and carbon dioxide travel in automated bucket lines down pipes to and from the lungs. The heart’s chambers are a pair of pistons, the stomach a conveyor belt, and the spinal cord a telephone system with switchboard operators directing calls.

The arresting image is the work of Fritz Kahn, M.D., a German gynecologist who in the 1920s wrote a series of popular books titled Das Leben des Menschen (The Life of Man) that strove to explain science and medicine to a broad audience. The colorful, intricately drawn diagram is one of three—all originally inserts in The Life of Man—displayed at the Harvey Cushing/John Hay Whitney Medical Library in January.

Largely forgotten until recently, Kahn’s books were famous for their detailed, innovative, and aesthetically pleasing illustrations, said Susan Wheeler, the medical library’s curator of prints, drawings, and historical posters. “I think he had an idea of making ideas handsome and accessible,” she said.

Today, Kahn is widely recognized as a pioneer of information graphics, the use of images and visual metaphors to convey information and ideas. He is often mentioned in the same breath as the Austrian Otto Neurath, who at about the same time invented isotype, the communication of data through pictographic charts.

Both men did their most famous work in post-World War I Central Europe, a time and place of social and political upheaval as well as technological and artistic innovation. That ferment sparked “a fireworks display of new aesthetic form,” wrote Uta and Thilo von Debschitz in their 2013 book, Fritz Kahn. In the introduction to the von Debschitzs’ book, graphic design historian Steven Heller likens Kahn to astronomer Carl Sagan in his ability to make science accessible to the ordinary person.

“The art of analogy was Kahn’s forte,” Heller wrote. “Kahn employed whatever visual trick he could cobble together for the end result: popular comprehension.”

The Life of Man series made Kahn Germany’s most famous popular science writer of the 1920s. A terrible artist, he commissioned others to render his ideas into illustrations.

Kahn, who was Jewish, fled Germany when the Nazis seized power. The new regime banned and burned his books. But in an ironic twist, Nazi authors plagiarized his work and illustrations, adding chapters on supposed racial superiority. Kahn later lived in France, the United States—gaining entry with the help of fellow German Jew Albert Einstein—Switzerland, and Denmark. He died in 1968, his work largely forgotten.

The other two Kahn posters displayed at the medical library are as fanciful as Man as an Industrial Palace, his most famous image. In one, an operator using a telescope and control panels illustrates how the brain tells the finger to press a doorbell. In the other, a warren of chambers containing conveyor belts, storage tanks, and other industrial devices demonstrates the circulation of blood and air through the body.

Wheeler said that the posters, donated to the medical library in the late 1970s and shown here for only the second time, elicited fascination and delight.

“There’s a kind of awed response to [them],” she said. “Visitors ask the same kind of questions, which is who did them and what were they for? But everyone expresses extreme enjoyment of them.”