Working charts for the stress analysis of elliptic rings
A NASA technical report of working charts from 1933 for stress analysis of elliptic rings, drawn for engineers who needed to read stress values from graphs. The pictures are plain line graphs with fine gridlines, curve families labelled by axis ratio a/b, and small inset diagrams of an ellipse with angle labels; a designer could take their clean, technical plotting style and the dense overlapping curve sets as structure.
