Mmmn.... "Thauma" = Greek for "Magic"; "Trope" = "something that turns". Therefore it be a "magic turn" innit.
Or rather tis a Victorian toy made from a disc with an image on either side of it and a thread at each side. When you rub the thread between your fingers it turns the disc and the images combine to form the illusion of one combined image... owing to the "persistence of vision". And I been playin around making some. Cos I like wasting time like that. Mrs D would also tell you that they share this persistence of vision thing with the animation malarky.
And when I was a youthy girl at art college way back then in the late 1960s... I did rather like the "optical" approach to paintings. This made me be considered a bit of a freak by the self-expressionful tutors. And so I was shut into a small studio with the only other student in the college who made optical paintings or Op-Art as they used to call it.
My days at art college were largely ruined by the tutors.
But then, they did not share my persistence of vision.