This research looks at the original finishes of the interior of the Cosmopolitan Club of Philadelphia, an important interior of the Modern age designed in 1930 by interior decorator Jules Bouy. Although the building design has been extensively researched in a 2012 Thesis in Historic Preservation by Sarah Peterson, the interior finishes are not well understood. This research augments Peterson’s study by determining color palettes, painting techniques, and paint types of four of the most important rooms of the Club: the Entry, the Lounge, the Library and the Stair Hall. Relying primarily on the microscopic study of paint cross sections, analysis is augmented by more specific methods of analysis, such as FTIR, SEM-EDS, GC-MS, and Raman spectroscopy. A palette of greys, blues and tans were found in one room, while three shades of green with pale yellow in another. The study identifies linseed oil as the paint’s binding media. Pigments are found to include ultramarine, Prussian blue, and chrome yellow. The resulting information is interpreted in the context of the building and of the period. Results led to recommendations for steps to restore Bouy’s polychrome interior
