From: Hrant H Papazian <[log in to unmask]>
I recently read a charming little book called "The Harmonograph"
by Anthony Ashton: it describes the mechanics of a device that
draws complex spiraling shapes using pendulums.
Oh! I shall really have to see if our library has a copy of that! I
remember building one in about 1965, and being endlessly fascinated by the
patterns it would create. I never knew a name for the device, though.
Does the book mention anything about who invented it, when, and what
prompted its discovery?