Melt the gum and the glue together in the water, then add the oxide of iron, and lastly put in enough chalk to make the whole a rather liquid paste. Apply to the parchment, which you have previously well rubbed with whiting, and, when dry, apply the gold-leaf with alcohol.”

Mixing the Size with Water.—A little of the size, taken from the jar (see above), is put in the saucer with a few drops of water to soak for an hour or two. It is then rubbed down with a finger-tip, care being taken to mix it very thoroughly and to avoid making bubbles. The right consistency is judged by experience—it should be thick rather than thin.

It is essential that all the ingredients be present in their right proportions, and the mixture should be stirred every now and then. Otherwise the earthy [p148] matter settles down, and the sticky parts, remaining in solution above, are liable to be used up. What is left in the saucer after use is apt to be deficient in its sticky parts, and it is best thrown away. Take out of the jar only what is required at the time, and mix a fresh lot the next time.

Bubbles, formed in the mixture, may be burst by a needle, or by adding a minute drop of oil of cloves.

Methods of Laying the Size.—The parchment or paper is laid flat on a table; if on a slope, the size would run down and lie unevenly. A quill pen with a finely cut nib and an extra long slit (about 58 inch) is used for laying the size. It is filled pretty full by means of a quill or a brush; if by the latter, special care must be taken to avoid bubbles.

Experiments should be made in various methods.

I. Perhaps the best way of laying the size, so that it may set properly and that the burnish may retain its brilliance, is to put on a thin coat with a pen—in the direct manner in which coloured Versals are made (q.v.)—and afterwards add two or three thin coats, allowing each coat to dry thoroughly. This requires considerable patience and skill, as it takes a long time, and there is a danger, in adding several coats, of spoiling the form by going over the edges.

II. The simplest method for ordinary gold letters is to make them with one extra thick coat[29] of size, exactly like coloured Versals—first a natural pen outline, and then the filling in (see fig. [81]). This requires some practice to do well, as the thicker size is more difficult to manage than the [p149] colour.[30] Very narrow parts—such as the thin strokes—are apt to be deficient in size, and therefore, while they are still wet, the pen—held nearly vertical with the nib in contact with the surface of the size—is moved slowly along it until the stroke has received sufficient size and is properly filled out.