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. HOW TO USE DRY COLOURS. To produce fine qualities of coloured printing inks by mixing pure dry colours with varnish, the printer will do well to give heed to the following particulars:— 1. No more should be mixed at a time than will be required for the job in hand.