Markantun de Dominis or Marco Antonio de Dominis was a Dalmatian ecclesiastic, Catholic archbishop, adjudged heretic of the Catholic Faith and a man of science. His scientific work: Tractatus de radiis visus et lucis in vitris, perspectivis et iride, published in 1611 Venice was (according to Isaac Newton) the first to develop the theory of the rainbow, by drawing attention to the fact that in each raindrop the light undergoes two refractions and an intermediate reflection. His claims to that distinction were later disputed in favour of Descartes.