Characteristics of radiation pyrometers
A 1915 technical paper from the National Bureau of Standards on radiation pyrometers, issued for physicists and industrial engineers measuring high temperatures. The plates are line diagrams of optical paths: converging and diverging ray bundles, lenses, mirrors, apertures and diaphragms drawn in thin rules with italic letter labels, useful as ray-trace schematics, dashed-axis layouts and instrument cross-sections.
