This paper considers educators’ debates over the proper place of the atomic theory in American and Ontario high schools during the first decade of the twentieth century, in the context of emerging, historic research on the nature of matter. In 1905, University of Toronto chemist William Lash Miller distributed a booklet instructing Ontario teachers how to teach chemistry without the atomic theory. According to Lash Miller and his Toronto colleagues, who edited a new textbook in 1906, teaching the atomic theory to beginners bred flawed and fuzzy reasoning. Lash Miller was a student of Wilhelm Ostwald, who famously doubted the reality of atoms until convinced by Jean Perrin’s 1908 experiments on Brownian motion. This paper shows that limiting the role of the atomic theory was part of an effort, both in Ontario and in the United States, to reorient the high school curriculum toward the expanding discipline of physical chemistry, specifically, a vision of physical chemistry indebted to Ostwald. Like the Toronto chemists, Chicago physical chemist Alexander Smith lamented high school textbooks’ overreliance on the atomic theory and promoted the use of laboratory terms. Both Lash Miller and Smith met with resistance from high school teachers, who defended the teaching of the atomic theory and advocated a competing view of beginners’ pedagogy. These debates were not settled primarily by appeals to evidence, but instead revolved around differing views of the needs and abilities of high school students.

The historiography of physics has reached a great degree of maturity and sophistication, providing many avenues to consider the making of science from a historical perspective. However, the big picture of the making of physics is characterized by a predominant narrative focused on a conception of disciplinary formation through leadership transfers in research among France, Germany, and Britain. This focus has provided the history of physics with a periodization, a geography, and a fundamental goal commonly considered to be conceptual and theoretical unification. In this paper, I suggest the interest of reassessing this picture by analyzing the temporal, national, and epistemological viewpoint from which it is written. I use for this purpose an exemplary case study: Adolphe Ganot’s physics textbooks in France and their translation by Edmund Atkinson in England. In this context, I suggest future avenues for the study of the making of physics as a discipline, which consider the canonical role of textbooks in disciplinary formation beyond the Kuhnian paradigm.