Abstract
This paper studies the semiotic,epistemological and historical aspects of Berzelianformulas in early nineteenth-century organicchemistry. I argue that Berzelian formulas wereenormously productive `paper tools' for representingchemical reactions of organic substances, and forcreating different pathways of reactions. Moreover, myanalysis of Jean Dumas's application of Berzelianformulas to model the creation of chloral from alcoholand chlorine exemplifies the role played by chemicalformulas in conceptual development (the concept ofsubstitution). Studying the dialectic of chemists'collectively shared goals and tools, I argue thatpaper tools, like laboratory instruments, areresources whose possibilities are not exhausted byscientists' attempts to achieve existing goals, butrather whose applications generate new goals. The term`paper tools' is introduced to emphasize that thepragmatic and syntactic aspects of symbol systems arefully comparable to physical laboratory tools.