The Building of a Book / A Series of Practical Articles Written by Experts in the Various Departments of Book Making and Distributing

by Unknown

After several sets of F-proofs have been taken, the form is carried to the moulding or "battery" room of the electrotyping department, where it leaves its perfect impress in the receptive wax. Thence it will later be returned to the composing room and taken apart and the type distributed, soon to be again set up in new combinations of letters and words. The little types making a page of verse to-day may do duty to-morrow in a page of a text-book in the higher mathematics.

After the type form has been warmed by placing it upon a steam table, an impression of it is taken in a composition resembling wax which is spread upon a metal slab to the thickness of about one-twelfth of an inch. Both the surface of the type and of the wax are thoroughly coated with plumbago or black lead, which serves as a lubricant to prevent the wax from adhering to the type.

As the blank places in the form would not provide sufficient depth in the plate, it is necessary to build them up in the wax mould by dropping more melted wax in such places to a height corresponding to the depth required in the plate, which is, of course, the reverse of the mould, and will show corresponding depressions wherever the mould has raised parts. If great care is not taken in this operation of "building-up," wax is apt to flow over into depressions in the mould, thereby effacing from it a part of the impression, and the plate appears later without the letters or words thus unintentionally blotted out. The reviser of the plate-proofs must watch carefully for such cases.

The mould is now thoroughly brushed over again with a better quality of black lead than before, and this furnishes the necessary metallic surface without which the copper would not deposit. Then it is "stopped out" by going over its edges with a hot iron, which melts the wax, destroys the black-lead coating, and confines the deposit of copper to its face.

After carefully clearing the face of the mould of all extraneous matter by a stream of water from a force-pump, it is washed with a solution of iron filings and blue vitriol which forms a primary copper facing. It is then suspended by a copper-connecting strip in a bath containing a solution of sulphate of copper, water, and sulphuric acid. Through the instrumentality of this solution, and the action of a current of electricity from a dynamo, copper particles separate from sheets of copper (called "anodes," which are also suspended in the bath) and deposit into the face of the mould, thus exactly reproducing the elevations and depressions of the form of type or illustrations of which the mould is an impression. After remaining in the bath about two hours, when the deposit of copper should be about as thick as a visiting card, the mould is taken from the bath and the copper shell removed from the wax by pouring boiling hot water upon it. A further washing in hot lye, and a bath in an acid pickle, completely removes every vestige of wax from the shell. The back of the shell is now moistened with soldering fluid and covered with a layer of tin-foil, which acts as a solder between the copper and the later backing of lead.

The shells are now placed face downward in a shallow pan, and melted lead is poured upon them until of a sufficient depth; then the whole mass is cooled off, and the solid lead plate with copper face is removed from the pan and carried to the finishing room, where it is planed down to a standard thickness of about one-seventh of an inch. The various pages in the cast are sawed apart, the guard-lines removed, side and foot edges bevelled, head edge trimmed square, and the open or blank parts of the plate lowered by a routing machine to a sufficient depth to prevent their showing later on the printed sheet.

Then a proof taken from the plates is carefully examined for imperfections, and the plates are corrected or repaired accordingly, and are now ready for the press.

Although, owing to the expense and to the fact that the plate is more or less weakened thereby, it is desirable to avoid as much as possible making alterations in the plates, they can be made, and the following is the course generally pursued. If the change involves but a letter or two, the letters in the plate are cut out and new type letters are inserted; but if the alteration involves a whole word or more, it is inadvisable to insert the lead type, owing to its being softer and less durable than the copper-faced plate, and it will therefore soon show more wear than the rest of the page; and so it is customary to reset and electrotype so much of the page as is necessary to incorporate the proposed alteration, and then to substitute this part of the page for the part to be altered, by cutting out the old and soldering in the new piece, which must of course exactly correspond in size.

As a patched plate is apt at any time to go to pieces on the press, and may destroy other plates around it, or may even damage the press itself, it is generally considered best to cast a new plate from the patched one. This does not, however, apply to plates in which only single letters or words have been inserted, but to those which have been cut apart their whole width for the insertion of one or more lines.

The plates having been finally approved, they are made up in groups (or "signatures") of sixteen, and packed in strong boxes for future storage. Each box generally contains three of these groups, or forty-eight plates, and is plainly marked with the title of the book and the numbers of the signatures contained therein.