At the turn of the twentieth century, in San Francisco, German optometrist George Mayerle created and published the “international” eye-test chart: “an artifact of an immigrant nation—produced by a German optician in a polyglot city where West met East (and which was then undergoing massive rebuilding after the 1906 earthquake)—and of a globalizing economy”.
Running through the middle of the chart, the seven vertical panels test for acuity of vision with characters in the Roman alphabet (for English, German, and other European readers) and also in Japanese, Chinese, Russian, and Hebrew. A panel in the center replaces the alphabetic characters with symbols for children and adults who were illiterate or who could not read any of the other writing systems offered. Directly above the center panel is a version of the radiant dial that tests for astigmatism. On either side of that are lines that test the muscular strength of the eyes. Finally, across the bottom, boxes test for color vision, a feature intended especially (according to one advertisement) for those working on railroads and steamboats
This beautiful bit of design is highlighted by the Circulating Now blog from the Historical Collections of the National Library of Medicine. The post also tells us a bit about Mayerle himself, who sounds like an interesting character, considered both scientific practitioner, but also being “right at home in optometry’s peddler tradition” selling tonics of all sorts.