And it had been a source of keen pleasure when, below the narrow ribbon of the violin-part, delicate, unyielding, substantial and governing the whole, he had suddenly perceived, where it was trying to surge upwards in a flowing tide of sound, the mass of the piano-part, multiform, coherent, level, and breaking everywhere in melody like the deep blue tumult of the sea, silvered and charmed into a minor key by the moonlight.