The third case, where something has been forgotten, is treated almost the same way. If it is only a very small thing, the stone need merely be scraped carefully. Then the drawing may be put in, preferably with a thicker ink. If the area is large, the stone must be ground where the design is to be added, coated with soap-water or oil of turpentine, and then treated as explained before. When the stone has been corrected and prepared for printing, it can be used at once or set aside for some length of time. In the latter case it should be inked with a firm color and coated delicately with gum solution. Then it can be held as long as desired. Coating with gum solution is advisable not merely for storing away, but for every interruption of printing that lasts more than five minutes. If a stone has stood longer than a day without being freshly inked, it must be wiped off first of all with gum solution and oil of turpentine, that it may take the color well, so that the very first impression may be perfect. During the progress of printing, the following points are important: Uniform distribution of water, the same of printing-color, frequent inking of the inking-roller, and the very greatest speed possible. In the main points the brush process is like that of the pen. The chief difference is that it is not possible to make the brush strokes as strong as those with the pen. Therefore, brush work does not resist etching so well and must not be treated too powerfully. Much depends on the treatment of the brush and the consistency of the ink. The brush does not permit such a flow of ink as does the pen, and generally requires one that is more fluid. A good brush ink is made as follows:-- Mix two parts of pure white wax and one part of good tallow soap into a mass not larger than a hazel nut. The ink loses its good properties quickly and should be made fresh day by day. Mix the two materials with a thick knife on a lukewarm (but positively not warm) stone, separate into small parts and moisten with rain water. As soon as the water has softened the mass a trifle, add as much lampblack as will lie on two knife points and mix the whole mass together once more till it is thoroughly mixed and quite firm. When required, a bit of this is rubbed down in a clean saucer with rain water. As a better flow of ink is needed for brush work than for pen work, it is evident that it would not be requisite to treat the stone with soap-water and oil of turpentine, as for pen work. However, it often pays to make certain fine lines with the pen, and therefore it is better to combine both processes and prepare the stone as for pen work. It is well, however, after drying the coating, to rub it very gently with dry sand, which will not make the pen strokes flow to any extent and still will prepare the stone so that it will take the brush strokes well and not make necessary such strong etching.