System of Architectural Ornament, Plate 16, Impromptu!

In 1922 the Art Institute’s recently opened Burnham Library of Architecture com-missioned Louis Sullivan to make drawings illustrating his renowned theories of architectural ornament. These masterpieces were published together as A System of Architectural Ornament, According with a Philosophy of Man’s Powers by the American Institute of Architects in 1924; this was Sullivan’s final statement about the geometry underlying both natural and man-made forms. In his search for an original American architecture, Sullivan drew his inspiration from nature, not unlike the nineteenth-century American poets and writers whom he emulated. Like them, he intended ornament to function evocatively as well as to represent organic growth, evolving from closed geometric units to open, efflorescent forms. In Impromptu!, the sixteenth of the twenty delicate drawings in his treatise, Sullivan produced one of his most open, vibrant, and fluent compositions. Giving free rein to expansive whiplash appendages and spiral stalks, the architect combined nature’s infinite creative variation and incessant change with an intense emotional expressionism. To convey these poetic nuances, Sullivan’s correlating notation describes the design as entering “the domain of Virtuosity, Romance and Symbolism.”