This paper considers a group of early modern scholars who combined philological and experimental practices in their investigation of ancient systems of measurement units. Inspired by the groundbreaking work of Guillaume Budé ("De asse," 1514), several humanists in the tradition of the treatises “de mensuris et ponderibus” developed an interest for the historical, rational examination of ancient measures. Some of them routinely weighed substances and materials as an aid to the philological study of ancient weights and measures. For example, Juan Bautista Villalpando (1552-1608) and Juan de Mariana (1536-1624) experimented on the weight of substances in a fully antiquarian fashion. This paper will focus on the little-studied research on historical metrology of two well-known authors, Georg Agricola (1494-1555) and Johannes Kepler (1571-1630). Agricola recommended that the philological study of texts on measures from ancient authors (Galen in particular) should be accompanied by trials and experiments on the weight of substances. Also, one of Kepler’s least studied works, the "Messekunst Archimedis" (1616), contains an extensive appendix, a self-standing antiquarian treatment of metrology and the study of ancient weights. Kepler’s examination of the subject combined philological analysis of ancient sources, the study of the tradition “de mensuris et ponderibus” and experimental investigation on the weight of substances. Overall, this early research on historical metrology shows a surprising mix of philological and experimental methodologies, an example of a so far under-examined “antiquarian experimentation” at the intersection of the history of the humanities and the sciences.
