Sorry I'm completely forgetting the name of the theory I'm thinking of. It involves planets moving on circles on harmonic spheres (as opposed to sjmply followin

Sorry I'm completely forgetting the name of the theory I'm thinking of. It involves planets moving on circles on harmonic spheres (as opposed to sjmply following great circles) and accounts fairly well for celestial motion. Its now mostly forgotten due to being a complete tangent on the way to Newtonian mechanics, but it was pretty clever.