“Contrary to opinions previously held by me, I hope to show that the medium of mosaic, rather than being painting with stones, or sculpture, is an art whose essential quality is texture and luminosity. This comes from the fact that the tesserae are placed in the cement so that they can reflect the smallest light. Painting also depends upon luminous vibrations, but with this difference—in order to see them they must be lit by a direct light which is not the case with mosaic since the facets of glass reflect their color and light when a minimum of light exists. A wall clothed in mosaic thus becomes a presence.”