RT @hist_astro: Combination portable sundial and instrument for calibrating sundials, c.1690–1710, French; brass, silver @metmuseum. http://t.co/rjG75Uf4s9
RT @hist_astro: Combination portable sundial and instrument for calibrating sundials, c.1690–1710, French; brass, silver @metmuseum. http://t.co/rjG75Uf4s9