Mathematical essays and recreations
A translated collection of popular mathematical essays by Hermann Schubert, issued in Chicago by Open Court in 1899 for general readers interested in geometry, magic squares and four-dimensional space. The figures are plain line diagrams printed in black on cream paper: triangles and pencils of straight lines crossed at labelled points, numbered intersections, dashed construction lines, and small captioned triangle sets, usable as spare geometric line work, numeric annotation, or diagram texture.
