There are two polishers,—one for the back and bands, and another for the sides. The oil applied on the cover previous to laying on the gold will be sufficient to make the polisher glide easily over the surface. The polisher must be heated, and well cleaned on a board, and passed quickly and evenly on the back, sides, or joints, as the case may be, taking especial care that it is not too hot, as the glaire would thereby be turned white and the work damaged in appearance, nor so cold as to give a bad polish.
The book, as gilt, must be first polished on the back, by taking it with the left hand, resting it on the table, and polished with the right hand by gliding backwards and forwards the smooth part of the polisher on the whole extent of the back. This not only polishes the surface, but smooths down the indentations formed upon the leather by the gilding-tools, bringing up the gilding to the surface. The polisher must be passed on such places only as it is wished to make brilliant, and great care taken not to touch the places intended to be left dull.
The sides are similarly polished, by laying the volume on the table, covered with baize, and passing the large iron quickly over, first from the fore-edge towards the groove, and then, by turning the volume in a contrary way, from the tail to the head.
If the joint requires polishing, the book is laid before the workman, the tail towards him, and the iron applied on the side next the groove, polishing the whole length of the board; then, turning round the volume, and bringing the fore-edge towards him, he polishes the side on the fore-edge, and, turning again, completes the whole by polishing the parts at the head and tail.
In addition to polishing, it is desirable to give to the sides the greatest possible smoothness by pressing them between polished tins or horns. These are placed on each side of the book even by the groove, put between pressing-boards, and screwed tightly in the press, and left for some time.
COLOURING.
Calf-skins of uniform tints, and also sprinkled, can now be obtained of English manufacturers; yet in many localities they are difficult to obtain. We therefore make known the chemical substances and ingredients required to execute them in the best manner. Marbling is a process that must be executed by the binder upon the cover, and, with many other revival styles, is again coming into vogue. The recipes given for the superior marbles and designs will, it is presumed, present this branch of the art on a higher footing, in a general point of view, than is usually accorded to it; and it is confidently asserted that not one of them will prove a failure, if attention to the directions be only given. Nothing has been omitted in the description of the substances best for use, the mode of preparing them, and the proceedings to be adopted, that can tend to give to the covers all the elegance and splendour of which they are susceptible. By the aid of these, assisted by some taste, the workman may vary the designs almost to infinity; but it must be admitted that, unless he is devoted to his art, no mere directions or casual advantages will enable him to succeed in the more complicated or delicate operations, while, with an ardour for it, all difficulties will be easily overcome.
CHEMICAL PREPARATIONS.
Under this head is included aqua regia, or killed spirits, nitric acid, marbling-water, and glaire prepared for marbling.
AQUA REGIA,