Depiction of a woman teaching geometry from a 1310 translation of Euclid’s Elements, initially written in 300 BC.
Alright, so this is actually pretty awesome. Quoting from the picture’s page on Wikimedia Commons:
In the Middle Ages, it is unusual to see women represented as teachers, in particular when the students appear to be monks. She is most likely the personification of Geometry, based on Martianus Capella’s famous book De Nuptiis Philologiae et Mercurii, [5th c.] a standard source for allegorical imagery of the seven liberal arts. Illustration at the beginning of Euclid’s Elementa, in the translation attributed to Adelard of Bath.
The original manuscript belongs to the British Library (catalog entry Burney 275). Here’s the same image with surrounding context:
See how it’s actually drawn in the bowl of a ‘p’ at the beginning of a paragraph? The big letters at the beginning of paragraphs are called drop caps in modern terminology. Back in the Middle Ages, important manuscripts often contained these illuminations inside drop caps, which in this case are called historiated initials.
Judging from the pictures in the BL catalog, which show several illuminations and flourishes, and from the attribution of the work to the Méliacin Master, this was not a cheap book! Just imagine the insane amount of work that went into producing a whole manuscript illustrated in this manner, or even the single illustration here at such a small scale—at a time when glasses had barely been invented!