Page:The practice of water-colour painting (IA cu31924014501971).pdf/245

effectively to give subtlety to a tempera picture. A vigorous lay-in can be completed by judicious over-work within comparatively few minutes, and without any destruction of the underpainting if ordinary care is taken in handling the pigments; and on a sharply granulated surface – like the antiponce pastel paper for instance – it is possible to add finishing touches over the underpainting almost immediately, and therefore to carry a sketch to completion with very great rapidity. It is best in painting on such a ground to thin the pigments considerably with the tempera medium for the first lay-in and to use them more solidly for the over-work, as with the thin colour the large masses of the subject and the main facts of the effect can be most tellingly blocked in, and with the solid pigment the details which give brilliancy and completeness to the picture can be most surely realised. Moreover, the thin colour sinks at once into the depressions of the granulated ground, while the solid touches lie rather on the projections, so what risk there may be of the underpainting working up is almost entirely obviated.