The unpublished physical and astronomical notes of the Accademia del Cimento

The Florentine Accademia del Cimento (1657-1667) was the first European academy of the Modern Era: its motto, “Provando e riprovando”, embodies the choice to put experimentalism at the core of the ten-year activ ity. From 1657 to 1667, the academicians carried out hundreds of experiments (during more than 600 academic sessions): while pneumatics and thermology were the predominant research lines, the Cimento also paid atten tion to physical phenomena and other areas, such as meteorology, natural sciences, and astronomy, making extensive use of scientific instruments. Despite this, only a small part of this whole set is collected in the only official publication of the Cimento, the Saggi di Naturali Esperienze (1667), and the reason for this choice is one of the ongoing issues and subject of historical studies. Fortunately, the experimental history of the Academy can be studied through the unpublished manuscript diaries kept in the Florentine Archives at the BNCF (Biblioteca Nazionale Centrale di Firenze). Starting from some of these selected documents, my speech will focus on physical experiments on magnetic and electri cal properties (”virtù“) of substances, pendulum motions, light and sound behaviours, all carried out at the Medicean Court. I will also present some astronomical observations of planets and other celestial phenomena (lunar and solar eclipses, comets) and the related correspondence with important European astronomers that brought to light evidence against the centuries-old tradition of the Ptolemaic geocentric model