Covers are generally decorated in some way; as a rule by means of the blocking press. Where they get any hand tooling, it is always done on the book when bound, for which no case is made in advance. Simple gold lines along the back and corners of the cover are excepted; such work is known as "filleting."
We make a distinction between gold tooling and blind tooling. The latter is simply an impression on the leather or other material without the use of gold, whilst the other is an impression upon a specially prepared leather or other surface, using gold leaf.
Skill in blocking depends first of all upon a tasteful and suitable selection and arrangement of the engraved blocks and letters necessary for the decoration and inscription.
The blocks, &c., are to be had ready made from the engravers in properly arranged sets; but still it is essential that the finisher should possess certain artistic taste and feeling, especially in making up the lettering. It must be borne in mind that in an inscription or title the principal part (word or line) must be distinguished by larger or heavier type; furthermore, two lines of equal length must never appear in an inscription. Short words (the, and, for, &c.) worked into an inscription as separate lines add considerably to its appearance. See pp. 148 to 153 for what is said on the arrangement of the title in hand lettering. The same applies to the arrangement of all lettering.
The blocks and letters are always fixed to the upper part of the press--the platen.
To enable alterations to be made quickly or to secure pieces which may have slipped, there is a draw-out plate made in all modern blocking presses. The engraved blocks are not affixed to this plate with glue but with cobblers' wax. The following is a practical way of managing the ornamental blocks: On a thin but very strong board about the size of the article to be blocked, the blocks are arranged with the backs uppermost, the engraved face being next to the board. This board is fixed with wax exactly in the centre of the lower part of the press--the table. By "exactly in the centre" it is to be understood that the centre of the various blocks brought together lies on or near the centre of the draw-out plate. If there are more and heavier blocks fixed to the upper than to the lower side of the plate, the latter must be lowered a little--in a word, the plate must be so adjusted that all parts receive equal pressure. It is only by making a few trials that one can learn exactly what is right.