This book presents research perspectives and open questions on the intersections between astronomy and chronometry. Their study is of crucial importance to the new historiography of observatories. On the one hand, pendulums were fundamental tools for astronomical observation, as measuring time was essential to record the transit of stars and organize astrographic charts. On the other hand, astronomical observation was the method employed for time determination before the introduction of atomic clocks in the mid-20th century. Chapters of this book cohere around 5 sections: starting from the 18th century, and going through the 19th and 20th, the relations between observatories and chronometry (and more generally between practices and materiality) are analyzed from the standpoint of the quest for precision, the certification of timepieces, the acquisition and use of specific apparatus, as well as the circulation of knowledge and of instruments on a global scale.
Introduction: Observatory Time.- Synchronising Paris in the Eighteenth
Century? Henry Sullys Meridian Line at Saint-Sulpice: Astronomy,
Clockmaking, and Timekeeping.- Instructions and Time Measurement at the Paris
Observatory (1667-1789).- The Chronometry Collection of the Palermo
Astronomical Observatory.- Hour by Hour, Day and Night: Splitting Time
between the Astronomical and Physical Observatories.- Timekeeping and Time
Balls at the Hamburg Observatory.- Determining Time, Eliminating the Personal
Equation and Introducing Quartz Clocks: The Neuchâtel Observatorys Operating
Chain in 1954.- The Nineteenth-Century Marine Chronometers of the Royal
Astronomical Observatory of the Spanish Navy in San Fernando.- The
Certification of Chronometers at the Neuchâtel Cantonal Observatory. Setting
up and Renewing Equipment and the Legal Framework for Certification
(1858-1912).- Astronomy and Chronometry: Institutions for Testing
Chronometers after the Foundation of the German Empire in 1871.- On the
Accuracy of Celestial and Terrestrial Clocks: The Merit of Felix Schmeidlers
Half-Century Monitoring of Two Riefler Clocks at Munich Observatory.- Who
Put That Hole In The Telescope? The Development of the Worlds Most Accurate
Timepiece.- Observatories, Marine Chronometers, and Terrestrial Applications:
From Chronometric Longitude Expeditions to Observational Efficiency.-
Astronomy and Chronometry: Experimental Practices to Improve Hydrography
during the Early Nineteenth Century.- Colonial Time Machines: Chronometry and
the Personal Equation between Europe and South Asia.- Paolo Brenni Scholar,
Educator and Artisan.- Beyond the Written Word. Paolo Brennis Foundational
Contribution to the Conservation of Scientific Instruments.
Gianenrico Bernasconi is an research professor in the history of technology at the University of Neuchâtel. His main field of research are the history of technology, the history of material culture, and the food history. His current research concerns more particularly the cultures of time measurement (18th-20th centuries). He is the PI of two SNSF-funded projects: The Cantonal Observatory of Neuchâtel (1858-1948): Cultures of Precision, Economy of Quality and the "Commodification" of Time (2018-2022) and Timekeeping, Chemistry, and Kitchen: The Formalization of Practices, 17th-18th Century (2020-2023). He is the author of Objets portatifs au Siècle des Lumières (Paris 2015), the co-editor (with S. Thürigen) of Material Histories of Time: Objects and Practices, 14th-19th Centuries (Berlin-Boston 2020), the co-editor (with G. Carnino et al.) of Les Réparations Dans lHistoire (Paris 2022), and the co-editor (with Marco Storni) of Early Modern Fire: Science, Technology, and the Urban Space (Leiden-Boston, 2025).
Ileana Chinnici is an astronomer at the INAF-Palermo Astronomical Observatory. Her main field of research is the history of astronomy and she is the author of many publications in this field. From 1996-2004 she was curator of the astronomical museum of the Observatory and is presently scientific advisor for its historical collections. Her interests are focused on the history of astronomy and astrophysics in the 19th century, especially exploiting archival resources. The 2021 Osterbrock Book Prize has been awarded to her biography of Jesuit scientist Angelo Secchi (1818-1878). She is currently member of the board of advisors of the Italian Astronomical Society, adjoint scholar of the Vatican Observatory and incoming President of the Scientific Instrument Commission of the International Union of History ad Philosophy of Science and Technology.
Marco Storni is a postodoctoral fellow at the Université libre de Bruxelles. After completing his PhD at the École Normale Supérieure of Paris and the University of Bologna, he has been a postdoctoral fellow at Ca' Foscari University of Venice and at the University of Neuchâtel. His research focuses on the history of science and of philosophy of science in the early modern period. He is the author of Maupertuis. Le philosophe, l'académicien, le polémiste (Paris 2022; winner of the Prize of the Fondation Del Duca-Institut de France 2023) and the co-editor, with Gianenrico Bernasconi, of Early Modern Fire: Science, Technology, and the Urban Space (Leiden-Boston 2025).
