Ring Dial - Brass Pocket Sundial - Equinoctial Ring Dial - Kala
Astronomical rings - Wikipedia
16 Century Astronomical Ring|Astronomical Sphere Finger Ring|12 Constellation Rotating Ring
A rare Ottoman brass equinoctial ring dial, signed by Mahmud Bey al-Falaki, Egypt, dated 1291 AH/1874 AD | Arts of the Islamic World & India including Fine Rugs and Carpets | 2021 | Sotheby's
Galileo's Instruments of Discovery | Science| Smithsonian Magazine