Note on research work by Helmholtz and Wien relating to the form of waves propagated along the surface of separation of two liquids
A 1928 NASA technical report note on Helmholtz and Wien's work on waves at the boundary between two liquids, written for aeronautical and scientific readers. The pictures are hand-drawn diagrams with labelled axes, shaded and dashed fluid regions, arrows for velocity, and a cross-section of a rising wave crest. A designer might take their clean line diagrams, hatching patterns and labelled coordinate schemes as technical graphic references.
