Wolfgang Metzger (1899-1979) was one of the most influential members of Gestalt psychology's second generation. Originally drawn to the study of perception and psychology by his teachers, Wolfgang Köhler and Max Wertheimer, Metzger went on to make many important contributions during a long and illustrious career. (Upon his death, a brief biography appeared in the American Journal of Psychology.
Some researchers consider Metzger's 1934 article "Beobachtungen über phaenomenale Identität" (Observations on phenomenal identity), to be one of the most important papers ever published on the perception of visual motion. In addition to many journal articles, Metzger published a number of books, including Psychologie - Die Entwicklung ihrer Grundannahmen seit der Einführung des Experiments (1st edition, 1954), and Gesetze des Sehens (1st edition, 1937).
To make Metzger's work more readily available in the English speaking world, here is a translation of Chapter 16, "Von gesehener Bewegung" (On seen motion), from Metzger's Gesetze des Sehens (2nd edition, 1953, Frankfurt am Main: Kramer Verlag).
The translation was prepared by Ulric Neisser (Department of Psychology, Cornell University), who most graciously allowed it to be made available here. Neisser's translation was prepared originally in 1958 for MIT's Lincoln Laboratories, Lexington, Massachusetts.
The illustrations, particularly color illustrations, are not as clear as one might like. In part this reflects the faded condition of the copy we worked from, in part it reflects some loss in the scanning process. Adjustment of your computer display's color and gamma seetings may help somewhat.
Ricardo B. Morant (Psychology Department, Brandeis University) kindly allowed his copy of Neisser's translation to be scanned into machine-readable form. Chris McLaughlin (Vision Lab, Brandeis University) scanned the text and figures, and formatted them for the web.
While this modest project was nearing completion, I learned of plans for a new, complete English translation of the first edition of Metzger's book. That effort testifies to the importance of Gesetze des Sehens.