Aero dopes and varnishes
A 1927 technical report on aero dopes and varnishes, the coatings applied to aircraft fabric, issued by the NASA Technical Reports Server archive and written for aeronautical engineers. Its one picture is a line graph plotting the weight of film in ounces per square yard against a numbered horizontal scale, with the curve rising steeply at the upper end. A designer would find only a plain engineering chart here, useful for its grid layout and axis labelling rather than for imagery.
