The measurement of maximum cylinder pressures
A 1929 NASA technical report on instruments for measuring peak pressure inside engine cylinders, aimed at engineers and researchers. Its pictures are plain line drawings and a graph: a piston-type maximum pressure indicator, an optical indicator with a mirror and photographic film, and a schematic engine test rig with a recording drum, spark point, and air bottle, plus a grid chart of pressure against area-to-weight ratio. A designer could draw on the clean diagrammatic style, the labelled cutaway technique, and the simple two-curve graph layout.
