"When divination by water was performed with a looking glass, it was called catoptromancy: sometimes they (the Greeks) dipped a looking glass into the water, when they desired to know what would become of a sick person: for as he looked well or ill in the glass, accordingly they presumed of his future condtion. Sometimes, also, glasses were used and the images of what should happen, without water."
William Potter, Greek Antiquities, 1859