Another way of embossing in high relief, which we believe to be here described for the first time, is as follows: The outline of the design must first be traced on the flesh side of the leather. This is done by placing blue transfer paper under the leather, with the blue side uppermost, while the design is being transferred to the surface of the leather with the tracing-point in the manner described on p. [20]. A chamois leather bag, about 16 × 12 inches in size, is filled with very fine, carefully sifted sand, and then sewn up as tightly as possible, so that the surface is quite taut. The bag is placed on the table, and the leather face downwards upon it. The steel ball is then rubbed to and fro, on the flesh side of the leather, at the point to be embossed, and the relief is produced as the sand yields under the pressure of the tool. The sand gives enough support to the leather, however, to prevent it stretching too much, as it would be liable to do if merely extended over a frame.
The next process is to open the incisions. This is not done till after the leather has been embossed in order not to further impair the strength of the leather at the outline, already diminished to some extent by cutting. The object of opening the incision is to facilitate the flattening of the outer edge so that it merges into the ground and the graduated modelling of the inner edge to form the softened outline of the ornament in relief.
5. Case of cut and embossed leather, cuir bouilli. Italian, 15th Century.
To obtain this soft effect, the modeller is gently passed from left to right over the angle formed by the inner edge of the incision and the surface of the modelling. The
tool may be lifted and the leather turned about to place it in the right position for this movement. The leather is frequently wetted (but not to such a degree, however, that the water oozes out of the surface when the modeller is used), and assumes the substance of wax. Should it show a tendency to rise after it has been depressed, it must be gone over again with the tool; if the leather is of good quality, it will keep the modelling permanently when it is once dry.
Care must be taken to avoid making a false impression; the least contact of the tool with the leather will leave a mark on the damp surface, which it is not always possible to efface from beneath.
Having dealt with cut and modelled leather, we now turn to modelling without cutting, the outline of the design being first simply marked out with the tracing-point, or with the opener held very slanting to avoid wrinkling the surface of the skin. This process should be adopted in preference to the preceding one, for comparatively thin skins which would not bear cutting. The relief may be obtained in the manner described above by working it up from the back of the leather, or the leather may be laid surface upwards on a cake of wax and the design brought out in low relief by depressing the background with the tool. Better results are obtained with the latter method. The wax is applied under the parts to be modelled, which must be accurately marked out for this purpose on the under side of the leather, and thin paper is pasted underneath it to keep it in place and prevent it sticking to the table; or a very smooth, thin tablet of wax is placed on stout cardboard under the entire piece of leather; when in position, the edges of the leather should be turned over and firmly fixed underneath the cardboard in such a manner as to prevent the wax forcing itself out under the pressure of the tool. The wax must be prepared with spirit to expel the grease or contact with it would stain the leather.
After thoroughly wetting the leather, the outline