The American Printer: A Manual of Typography / Containing practical directions for managing all departments of a printing office, as well as complete instructions for apprentices; with several useful tables, numerous schemes for imposing forms in every variety, hints to authors, etc.

by Thomas MacKellar

PRINTING IN COLOURS.

When red and black are to be printed on the same sheet,—the same process being applicable to all other colours,—the form is made ready in the usual way, and a chalk-line is traced around the outside of the chase on the press-bed, to show the exact situation in which the form must be replaced after having been lifted. The form is then laid with its face downward on a letter-board covered with the press-blankets. The words marked in the proof to be printed red are then forced down, and Nonpareil reglets nicely fitted into the vacancies, which raise the red lines and words an equal distance from the other matter. A sheet of paper is then pasted on the form, to keep the Nonpareil underlays in their proper places. The form is again laid on the press, observing the utmost care in placing it in its original position as indicated by the marks before made on the bed.

INK STONE AND MULLER.

It must then be made perfectly fast to the corner irons, as it is highly important that it remain firm and immovable during its stay on the press. The frisket (which is covered with strong paper) is then put on, the form rolled over with the red ink, and an impression made on it. The red words are then cut out with a sharp-pointed penknife, with so much nicety as not to admit the smallest soil on the paper from the other matter.

The red being finished and the form washed, the compositor unlocks it, (this should be done on the imposing-stone, as the pressman can easily lay it agreeably to the marks made on the press,) and draws out the red lines, filling up the space with quadrates. When this is done, the pressman cuts out the frisket for the black. An extra pair of points are used to prevent the black from falling on the red, or, as it is technically termed, riding. Generally, when a great number is to be printed, as many forms are used as there are colours to be printed. Another method of placing the underlays is adopted for broadsides, &c. with large letter and with but two or three lines of red. The red lines are taken out on the press, and underlays are put in, upon which the lines are placed, and the frisket is cut out as before mentioned.

A more expeditious method can be employed for forms in which the lines of one colour are not too numerous to be easily lifted. After the form is ready, and the various colours are marked on the proof, a skeleton form is made up, with labour-saving quotation furniture or wood furniture fitted into the spaces of all the lines except those of the colour to be first printed. When the first colour is printed, its lines are lifted from the form, and the spaces filled with furniture, and the lines for the next colour are set in their proper places and printed; and so on till the job is completed.

The custom of printing broadsides, &c. with several colours is so common that ink-makers generally now manufacture coloured inks; consequently the printer can be supplied without the delay and labour of making. We give the following particulars, however, for the benefit of those who wish to prepare their own colours.

Varnish is the common menstruum adopted for all colours in printing. Red is the colour generally used with black. Trieste or English Vermilion, with a small portion of lake, produces a beautiful red, which should be ground with a muller on a marble slab till it be perfectly smooth. If it be in the smallest degree gritty, it clogs the form, and consequently produces a thick and imperfect impression; no pains should, therefore, be spared to render it perfectly smooth; it may then be made to work as clear and free from picks as black. A cheaper red, but not so brilliant, may be prepared with orange mineral, rose pink, and red lead.

Prussian blue makes also an excellent colour, but will require much time and labour to make it perfectly smooth. It is also ground with the best varnish, but made considerably thicker, by allowing a greater portion of colour with the same quantity of varnish than the red; it will then work clear and free from picks. As this colour dries rather rapidly, the rollers should be frequently washed.

Other colours may be made,—viz., lake and Indian red, which produce a deep red; verditure and indigo, for blues; orpiment, pink, yellow ochre, for yellows; verdigris and green verditure, for green, &c. All these colours should be ground with soft varnish, being in themselves driers, or they will choke up the form. The consistency of the ink must be governed by the quality of the work to be executed. For a posting-bill or coarse job, the ink should be very thin, the proportion of varnish being much greater than required for fine work. Should the work be a wood-cut, or small type, the pigment should be made as thick as possible.

The best colours for printing are those of the lightest body and brightest colour.