The paint used in flatting consists of white lead with which, of course, the necessary coloring matter is mixed, turpentine alone being used as the medium with which the paint is thinned. The color should be rather lighter than is required, as it darkens a little whilst drying; a brushful should therefore be tried before the whole surface is painted in order to avoid subsequent disappointment. In order to assist in drying, japanners' gold size is sometimes used instead of driers.
Although it is, of course, necessary that the coat preceding the flatting should be dry, it ought not to be absolutely hard, for it is necessary that the flatting, which is mixed with turpentine only, should slightly dissolve the surface, so as to become in a degree incorporated with it, by which much beauty and solidity is obtained, whereas, if the previous coat had become quite hard the flatting would in most cases appear streaky when dry and would be liable to crack or peel off.
Owing to the special composition of the paint used in flatting, it dries very rapidly and two men should be engaged at once in flatting a wall. A plank placed across two step-ladders, or otherwise supported, is placed in front of the wall at about half the height from the ground. One of the painters stands on this whilst the other stands on the ground. The last mentioned commences the work, painting a strip about 18 inches wide and carrying it up as high as he can conveniently reach, he works rapidly, crossing occasionally, so that no brush marks in any one direction may be visible, laying off very lightly; that is, continuing the action of his brush, withdrawing it gradually so that the points of the hairs may only skim lightly over the work.
The painter above proceeds with the operation from the line where his fellow painter left it, and carries it up to the top of the wall, the first painter meanwhile getting on with another strip, both painters being exceedingly careful
