Hilbert's and Cohn-Vossen's wonderful book "Anschauliche Geometrie" ("Geometry and the Imagination") from 1932 contains a lot of great illustrations which, given the time of publication, must have been drawn by hand. I couldn't find a mention in the book about who did them. (The photos of the 3D models are mentioned, but not the drawings unless I missed it somehow.)
Does anyone know who created the drawings and how they were made at that time? Was it some unknown graphical artists or maybe Cohn-Vossen himself?