DRYING.
When the painting has been completed, it should dry very slowly, and it would be better, if possible, to effect this by placing it in a moist, cool place. It is, however, difficult to handle a piece of ware when wet. The clay is in a very soft state, and a sudden jar might cause the vase to fall to pieces.
If the vase has not been in proper condition for painting, or has dried too quickly, it will, after some hours have elapsed, begin to show fine cracks upon the surface of the painting. These may be stopped, before they have gone too far, by passing a modeling tool over them, or, if the crack has become too deep for this treatment, it may be filled with clay as nearly as possible in the state at which the body of the ware has arrived. If the cracks are allowed to go too far it will be difficult to stop them, as they may have extended into the body of the ware.
If the piece is permitted to go to the firing with any cracks, however small upon its surface, they will become widened in the firing, and, especially after the glazing, will show very distinctly.
In the biscuit, they may be stopped by filling them with powdered clay mixed with gum water. But an ounce of prevention is worth a pound of cure, and the safest method is to prevent their appearance in the first place. If this can not be done, they must be stopped as soon as they appear. The finer clays seem to have a greater tendency to crack in drying, and when the cracks have appeared, they are more difficult to stop than in other clays.