XLV National Congress of the Italian Society for the History of Physics and Astronomy

Antonio Maria Jaci: A Competitor for the British Prize for Determining Longitude at Sea

12 Sept 2025, 10:20

25m

Aula Magna (DIFI-Università di Genova)

La Fisica e il Mare: conoscere, navigare, esplorare / Physics and the Sea: Knowing, Sailing, Exploring

Speaker

Tuscano, Maria Luisa (Associata INAF-OAPA; SISFA)

Description

Among the many scientific interests of Antonio Maria Jaci from Messina are his studies on the determination of longitude at sea, the results of which were presented to the British Board of Longitude.
After an initial instrumental approach in 1787, Jaci devoted himself to an astronomical formulation published in 1798 and refined with an addition in 1813.
Although it did not win the prize, the study was considered by the committee to be the best of those received.
The aim of this report is to present these peculiar studies by Jaci and to retrace the events related to them in the socio-political context of Messina.