A 'gnomon' is a pointer on which device?
Gnomon Gnomon A gnomon ([ˈnoʊmɒn], from Greek , "gnōmōn", literally: "one that knows or examines") is the part of a sundial that casts a shadow. The term is used for a variety of purposes in mathematics and other fields. A painted stick dating from 2300 BC was excavated at the astronomical site of Taosi is the oldest gnomon known in China. The gnomon was widely used in ancient China from the second century BC onward in order determine the changes in seasons, orientation, and geographical latitude. The ancient Chinese used shadow measurements for creating calendars that are mentioned in several ancient
Gnomon of Saint-Sulpice Gnomon of Saint-Sulpice The Gnomon of Saint-Sulpice is an astronomical measurement device located in the Church of Saint-Sulpice ("Église Saint-Sulpice") in Paris, France. It is a gnomon, a device designed to cast a shadow on the ground in order to determine the position of the sun in the sky. In early modern times, other gnomons were also built in several Italian and French churches in order to better calculate astronomical events. Those churches are Santa Maria del Fiore in Florence, San Petronio in Bologna, and the Church of the Certosa in Rome. These gnomons ultimately fell into disuse with the