Experiments on self-ignition of liquid fuels
A 1926 technical report from the NASA Technical Reports Server, published as an experimental study of self-ignition in liquid fuels for engineers and researchers. Its pictures are dense engineering charts with curved state-line graphs, shaded regions, and labelled axes in degrees, atmospheres and air density, showing how pressure and temperature thresholds divide zones. A designer might borrow the grid-and-curve layout, the hatched shading and the thin graph lettering as an austere technical motif.
