Reading Stone

branch of study: optics
inventor: west european monks as accounted by Ibn Al Haitham, around 1240

A Reading Stone is a thick plano-convex lens and can be considered to be the prototype of modern magnifying glasses. It was and still is put to use to magnify minute writings.

further reading

Belting, Hans (2008): Florenz und Bagdad. Eine westöstliche Geschichte des Blicks. München: Beck.