The Element of the Table: Visual Discourse and the Preperiodic Representation of Chemical Classification

Visual representations do things: they can sit quietly and be observed; they may aid in the performance of some activity, let's say, in science; they may act as repositories for previously compiled information; they may, through the format of their presentation, guide users or readers toward new ideas, or new practices. In science, and in chemistry particularly, visual representations are vital components of the material culture of practice. (Such an observation is not new.) Classifications in the sciences can be described with many of the same terms as visual representations. Classifications do things: they compile the past; they frame the future; they aid in the practice of a science; either they may be embedded within a theoretical edifice, or a theory may be embedded within them (if there is a difference). When we combine these two singularly rich subjects in scientific and artistic studies to focus on how classification schemes are visually represented, another view of history opens up that questions a presumed temporal order: here the representation is not necessarily the end point of a study; instead, it can be viewed as a productive contributor to the process that creates classifications and science. Those representations have a dual temporal direction, bringing the past into the present while also pointing to the future. Chemistry tables in particular exemplify this role in the practice of chemistry by acting as complex symbol systems defined by tabulations in grids, boxes, and spaces.

This paper is a study in the visual representation of chemical classification. In it, I discuss the active function of tables in the history of chemistry, arguing that those dynamic roles have in fact been enabled and fostered by their visually representative characteristics. To this end, I have two main goals. The first, fairly modestly, is to comment on the dual function of tables that looks to the past by collecting empirical information while directing practice toward the future by providing a view of how chemical substances relate to one another. The second, in which I expand the literature on serial linguistics to include spatial and graphic symbol systems, is to show that the visual discourse of the tables can help us understand that dual role. One popular story, of course, is that the iconic Mendeleevian periodic table of 1869 owes its glory to its uncanny ability to predict the unknown (directing practice toward the future), and as such is a paradigmatic historical example of dually collecting the past and guiding practice forward. But this accomplishment has its own history, one understood better when tables from the history of chemistry are treated as complex symbol systems. In fact, in what follows, I take the introduction of the periodic table as the end point to my story.

In general, then, I treat the chemistry table as a technology of representation, or a representational tool—a device used to perform a task—the visual grammar of which could be read. My primary contribution here is to take the idea of a linguistic study of the table (something that can be read) and add to it the idea of a visual study of classifications (a representation for which it mattered how it looked). The theme of treating the table as a discursive visual tool speaks to ideas of visual cognition, of the importance of nomenclature and language, and of how the construction and use of the table may be thought of in terms of a "paper tool."¹ While the history of the table is one where both linguistic and pictorial symbols play a central role—since the occupant of the table (say, an alchemical symbol, or the letters "Hg") is a kind of simple symbol, while the table itself is a complex symbol—I will focus here, for the most part, on the actual composite table as a visual representation.² This will make more sense as I progress through my discussion. Here is the important point: the table as a pictorial visual representation was not capably reducible to linguistic expression. That is, the visual arrangement of the table...