The passenger car ventilation system of the Pennsylvania Railroad Company
A 1904 technical report by chemist Charles B. Dudley, issued by the Pennsylvania Railroad's Altoona works for railway engineers and mechanical officers, on how passenger coaches were ventilated. The plates are fine-line engineering drawings: cross-sections and long elevations of a coach showing paneled interior walls, upholstered seats, clerestory roof vents, underfloor ducts and airflow traced as wavy lines, with letter keys useful as diagram vocabulary, ornamental panel grids and vehicle silhouettes.
