The ring unfolds into an armillary sphere, used to show the movement of the planets around the sun.
The ring unfolds into an armillary sphere, used to show the movement of the planets around the sun. (England, 1750 - 1800) -- source link
The ring unfolds into an armillary sphere, used to show the movement of the planets around the sun. (England, 1750 - 1800) -- source link