Color-Printing.
III.-Primary Colors, Tints, Shades, and Secondaries.

Before proceeding with the present subject it is necessary to say a few words regarding color, and those terms which are applied to it. In the first place, every color has its three constants: Hue (color in its truest form), Purity (freedom from white or black), and Brilliancy or Luminosity (the power the color possesses of emitting light.) In the second place, every color is capable of being reduced or darkened, producing Tints or Shades. For instance, let us place upon our ink-slab, or better still, a sheet of white card, three little pieces of the brightest red ink obtainable, and into No. 1 put a particle of black, and into No. 3 a similar quantity of white: by so doing we will obtain a good illustration of the terms Shade and Tint. In No. 1 we have the red a shade darker than in No. 2; in No. 2, the normal color; and in No. 3 the tint of No. 2. Thus it will be understood that when we speak of the Shade of a color, we mean the normal color darkened by the admixture of black; and when we use the term Tint, we mean the color reduced by being mixed with white. An experiment like the foregoing is very interesting, but should be continued further. A good idea is to take three or four long strips of good white paper (cream laid) or Bristol board, and after equipping ourselves with the three primary colors, red, blue, and yellow, and a good supply of black and white, to place in the centre of our card a spot or square patch of the normal color, as in the first experiment, and then on the one side reduce the same by the addition of white, and on the other side darken it by mixing with the black. These colors should be added in proportion, say, to 95 of the normal color add 5 parts of the white or black, and so on, reducing the one and increasing the other at the rate of 5 parts, until eight or ten different tints and shades are produced, or until you have on the one hand the color darkened to black, and on the other a white. If these strips are kept, and the number of parts marked, they are very useful for reference, as it can be seen at a glance how much white or black it is necessary to mix with a color to produce a given shade or tint. This system may be carried out in the mixing of the primaries to form secondary colors, by which means every tone of color can be produced; but care should be taken to adhere to the use of parts, if they are to be kept for reference. To a practical color-printer, the benefit of a set of color-grade slips is easily seen. He can, without any loss of time, consult them, and mix his inks, knowing that he will produce the tone, shade, or tint he desires. He can also, if he has made his surfaces of color large enough, place two or three colors together, and study their harmony, or by placing a sheet of paper, with a hole cut in it, over the color to be used, ascertain the effect when printed thereon.

The use of tints being entirely subordinate to that of positive colors, the remarks « on tints and their use » would be of little or no value to those who are entering upon the study of color-printing until we have given some idea of the positive colors, hues, shades, or tones that co-operate in making a complete and artistic piece of work. It is not our intention to produce an elaborate table of colors in pairs, triplets, &c., but simply to give what little information lies in our power to those who take an interest in their profession, and are desirous of bringing their work up to as near a state of perfection as possible. We do not give the results of the experiments we have tried as absolutely correct. We may not consider the combination of certain colors to be so good as others might, and vice versa; but with the assistance of a box of water-colors, and a little trouble and perseverance, those who are interested in color-work can experiment for themselves, and will perhaps be able to correct any errors we may have made. In working pairs of colors, we must remember that by the placing of one alongside another we will either increase the density or brightness of the one and reduce the other, or we will produce an apparent change in both. Thus, the red lines in a card (which is to be worked in red and black) will not appear nearly so bright before the black is printed as they will when the job is complete. Again, if we bring the two colors orange and violet together, we will find that the orange will incline to yellow, and the violet appear to have a bluish tinge. It will be seen by these remarks that a study of color is necessary before any reliance can be placed upon the appearance of the combination before it is printed, and that in every instance where it is in any way possible the colors should be brought into juxtaposition. The majority of printers in New Zealand keep to those colors which are supplied ready for use, and do not indulge in combinations outside of red and blue, or blue and black, with sometimes a little gold. In these they divide the lines so that the colors fall alternately, or nearly so, giving the work a striped appearance. We have always found, and consider it the rule, that two-thirds of the lines should be worked in the one color, and the rest in the other, i.e. a bill or poster worked in blue and red will be entirely spoilt if the colors are divided to fall alternately; but print, say, two or three lines at the most in red and the remainder in blue, and a very different result will be obtained. Now, in closing, we will give a few of those colors which, when worked in pairs, produce a pleasing combination, and which we have very seldom seen used, viz: orange-red with violet or turquoise blue; orange with violet-blue or blue-green; scarlet with turquoise or light blue; red with greenish yellow; greenish yellow with purple or normal blue; and others. In all combinations of colors, the card or paper to be printed must be of a tint suitable to those worked thereon. In the above pairs, we have supposed a white ground to be used; but in all classes of artistic work we prefer a tinted background.