I have endeavoured in this treatise to place before students some practical hints in the methods and processes of fresco painting, which are the out come of my experience in the practice of the buon fresco, and the spirit-fresco systems of wall decoration. As to the stereochrome, or German water-glass, and its later variety, the Keims pro cess of fresco painting, I do not pretend to have a definite knowledge, having no practical experience in painting in these methods, but, on seeing the condition of some frescos in England which have been executed in stereochromy, I should prefer to trust to the buon-fresco or to the spirit-fresco mediums when it is a question of the permanency of wall paintings.