Alternating-Current Equipment for the Measurement of Fluctuations of Air Speed in Turbulent Flow
This is a 1937 report from the National Advisory Committee for Aeronautics, issued as part of its technical report series and aimed at engineers and researchers in aerodynamics. The single photograph shows a laboratory bench with a tall instrument panel of dials, meters and switches beside a wooden table, under a large fan blade. A designer might take from it the dense, functional look of mid-century laboratory control panels, with grid-like arrays of gauges and a stark black-and-white documentary tone.
