 Melchior concentrated on acquisition and Sulpiz on research.Boisserée developed a new theory of the history of German painting, rejecting the idea that it had evolved gradually from crude beginnings; he proposed instead that a refined medieval style, ultimately derived from Byzantine prototypes had flourished, until the art was revolutionised by Jan van Eyck.In 1810 the brothers put their collection on public display in a palace in Heidelberg, attracting enthusiastic attention from Romantic circles.