Annual report of the National Advisory Committee for Aeronautics (5th).administrative report including Technical Reports nos. 51 to 82
This is an annual report of the National Advisory Committee for Aeronautics, issued in 1920 by the United States government agency for aviation research and its technical staff. The pictures are plain engineering plates: grid-ruled line graphs of gas leakage and pressure curves for spark plugs, plus small cross-section drawings of plug bodies. A designer might take from them the restrained chart layouts, boxed captions, and fine hatched line work typical of early technical reporting.
