Suminagashi or "floating ink" is the process of marbling plain paper with water and ink to transform it into something vibrant and colorful. The technique originated in China over 2,000 years ago, but was practiced by Shinto priests in Japan starting in the 12th century. The basic technique remains largely unchanged, despite more modern tools sometimes being used.
This art of floating ink requires a steady hand, both in applying the ink or paint to the water, and then in placing the paper on the surface to pick up the ink. The success of the technique also depends heavily on a grasp of fluid dynamics, in addition to basic artistic ability. The artistic side of things takes on more importance depending on the complexity of the image being painted.
Suminagashi ; painting on water