louis sullivan, a founding member of the chicago school of architecture, is best known for his pioneering designs of skyscrapers. it was a century ago that sullivan declared "form follows function," a statement that in time became a modernist shibboleth. but unlike modernists, sullivan also contended that form could, and should, be decorated to enhance its expression. thus we have such unique designs by sullivan as the merchants national bank in grinnell, iowa (above). in his waning years, a group of admiring colleagues commissioned sullivan to write and illustrate some thoughts about the craft to which he had given so much. the result was a collection of manuscripts and drawings exploring in magnificent detail a theory of architectural ornamentation based primarily on botanical forms. these documents, housed in the art institute of chicago, are presented in this single, oversized volume, with an essay by lauren weingarden and a foreword by john zukowsky and susan glover godlewski.