Effect of Aging on Taut Rubber Diaphragms
This NACA Technical Note No. 409 from 1932, issued by the National Advisory Committee for Aeronautics in the United States, reports engineering test results for aircraft instrument makers and researchers on how aging changes taut rubber diaphragms. The plates are plain technical graphs and photographs with no decoration. A designer could draw on them for their restrained, grid-based chart layouts, with dashed and solid line series, numbered curve labels and hand-set lettering in a utilitarian mid-century typewriter style.
