Recording of a lecture delivered on February 20, 2026, by Annapolis tutor Leah Lasell, as part of the Formal Lecture Series.

Ms. Lasell offers the following description: "Antoine Lavoisier claims that there is no free caloric in his Elementary Treatise on Chemistry. Less than twenty years later, Jane Marcet, in her Conversations on Chemistry (1806), claims that there is. Moreover, she argues that free caloric is essential for understanding temperature equilibrium. Who is right? We will investigate this question as we consider the many phenomena, experiments, and theories that Marcet presents through conversations in the laboratory between Mrs. B, Caroline, and Emily. Marcet’s treatise might be unfamiliar to our community. Marcet’s Conversations on Chemistry is among the most influential and widely read chemistry textbooks written since Lavoisier re-founded chemistry in the late 18th century."