An Instrument for Recording the Position of Airplane Control Surfaces
A 1923 technical report from the NASA Technical Reports Server, a dated record of an aeronautical instrument rather than a book, with its figures numbered Fig. 1 to Fig. 3 for engineers. The photographs show a recording device with dial and linkage parts photographed from several angles, plus a graph of traced lines; a designer could take its plain, labelled engineering-photo layout and the mechanical forms of the apparatus as reference for technical diagrams.
