Postage stamps are designed to convey messages that reverberate symbolically with broad swaths of the public, and their content has been employed as a window into how members of the public understand the ideas represented therein. In this rhetorical analysis, we analyze Philadelphia's Science History Institute's Witco Stamp Collection, which features 430 stamps from countries around the globe dating from 1910 to 1983, to identify how chemistry is portrayed in this ubiquitous medium. We find the vernacular of science reflected and supported by these images functions to (a) define chemistry in terms of its invisibility and abstraction; (b) uphold chemical operations as instrumental and daedal, or exceptional, in nature; and (c) delineate practitioners of chemistry as-on the whole-privileged and preternatural. Our findings reveal some of the overarching communicative tools made available to twentieth-century non-experts for articulating chemistry as an enterprise and reveal how those tools positioned chemistry in terms of values related to opacity and exclusivity.
Keywords: postage stamps; public understanding of science; rhetoric of science; science communication; vernacular science.