object
Reading stone
A named planoconvex rock-crystal or glass hemisphere laid on text to enlarge letters. Not spectacles, not a modern magnifying-glass, and not a bare crystal dump.
Also known as Visby lens · Rock-crystal reading stone
object
A named planoconvex rock-crystal or glass hemisphere laid on text to enlarge letters. Not spectacles, not a modern magnifying-glass, and not a bare crystal dump.
Also known as Visby lens · Rock-crystal reading stone