Landscape Painting/Chapter 9
IX
PIGMENTS
The question of the medium in which the painter shall execute his pictures is an affair of temperament. Each artist must consult his own feelings in this matter and select the medium which is to him the most sympathetic. To-day, there are practically but three systems of painting in common use, tempera having gone out of vogue, and fresco having very wisely been discarded in favor of better and sounder methods. The three remaining methods are, of course, pastel, water-color, and oil. Each of these has its own special advantages, and its countervailing disadvantages. Pastel, the most exquisite and fascinating of the three is also technically considered the most dangerous. It has, indeed, so many drawbacks on the material side that only the most thoroughly trained technician is able to avoid them all, and thus assure to his picture the permanence which is a first essential in any work of art. To begin with, it is the most fragile of materials. If a fixative is used it must be applied with a sure knowledge of the results to be obtained; for any carelessness or ignorance of manipulation during this delicate process will result in a certain loss of the surface bloom—the quality which more than anything else gives to pastels their exquisite charm. This statement applies more particularly to the painting in which the pastel is applied as a heavy coat over the whole surface of the canvas, and in which, therefore, fixing is an absolute necessity. When the pastel is used meagrely, and the surplus pigment is thoroughly shaken off, a pastel is nearly as indestructible as any other drawing, and this without the use of fixatives. But the worst shortcoming of pastel is its tendency to fade. This is unnecessary and is due solely to carelessness on the part of the manufacturers. The remedy, therefore, is to patronize only the most reliable makers.
Water-color has many of the charms of pastel, with practically no demerits. Its permanence is amply demonstrated by the cartoons of Raphael and Leonardo, while it gives to our work an airy delicacy that can be secured by no other means. Its only disadvantage is also one of its chief attractions—the element of uncertainty always present, for the color dries out a tone lighter than the freshly applied wash, and of course only long training enables one to discount with absolute certainty this subtle change of tone. However, we must admit that its usefulness is limited to comparatively light effects, and to pictures of moderate size, as it lacks the necessary depth and power for low-toned pictures or for canvases of large dimensions. As the lead factor is not present in water-color work, almost the whole scale of pigments may be used with impunity and with reasonable certainty of permanence.
But of all the methods of painting yet discovered, painting in oil is unquestionably the most valuable and the most satisfactory in its general results. The range of its power is only limited to the power of the pigments at our command; and its permanence depends only on our care in the selection of these pigments. In this respect, however, it must be admitted that our palette is still far from ideal.
That in this age of chemical conquest we should still be using the sixteenth century colors; still be forced to pick and choose our pigments in the constant fear of chemical change, is a pointed comment on the intelligence of the artist fraternity. Had painters been able to combine in a united demand, they would long ago have had a palette as brilliant as the rainbow and as enduring as the pyramids. They ask no impossibility. Indeed, the solution of this problem would be a comparatively simple matter for the modern chemist, a mere nothing in comparison with the prodigies that have been wrought in the domain of steel and in the field of electricity. But alas! from the very nature of things, concerted action was impossible. The artist is a hopeless individualist. Were he able to sink his individuality in any merger, he would no longer be an artist. I have in mind a dinner given by a benevolent lover of art and artists, to which a dozen prominent painters were bidden, that they might explain their needs to an eminent chemist who was the guest of the evening. I shall not soon forget the bewilderment of the man of science at the end of the conference. In less than an hour he had received a dozen widely varying accounts of the needs of the profession, each one describing the special and individual needs of a special painter. Moreover, the discussion was so filled with gay and reckless persiflage, so shot through with wit and repartee, that it was hopeless to attempt to separate the light from the serious. It was a very gay party, but it advanced little the cause of sound color.
If, therefore, artists are ever to secure the pigments which they need, the demand must come from some alien 
E. W. Redfield—"The Red Barn"
source. Fortunately, this demand has already arisen. The manufacturers of print goods all over the world are intisting upon pigments which will remain permanent under the strong rays of the tropical sun, and which will at the same time resist the action of the various alkalies and acids they are sure to encounter in the wash-tub. To meet this demand one great firm of color-makers has a hundred expert chemists employed upon the problem. Already they have achieved one definite and splendid result—a synthetic red which is absolutely neutral, chemically considered, and ten times more powerful than the best vermilion. As an artist's color, it replaces almost all the other red pigments which we have inherited from the past. The same chemists have an equally powerful yellow and blue under careful observation, and it is highly probable that in another year or two these, also, will be given to the world. Now it is evident that if painters can secure these three primary colors in two values, a light and a dark shade, they will, with the addition of white and black, have a perfect palette; as all of the secondary and tertiary colors, such as orange, green, violet, and their various derivatives can be compounded by an admixture of these original pigments.
But while we may hope for the completion of the new color-scale, it would be foolish prematurely to assume it as assured. In the meantime, we must act as if we were always to be dependent upon the old hereditary palette. That splendid and durable results can be secured through its use is amply proved by the superb examples of the old masters which have come down to us in a perfect state of preservation. All that is required is a little care and intelligence in the selection of the pigments. Lead is the one dangerous factor. If we were willing to take from the palette the white lead and the chromes, which have also a lead basis, we could use almost all the other pigments with impunity. But our only substitute for white lead is zinc white, which has the disadvantage of being so extremely brittle when hard-dry, that it cracks when the canvas is rolled, or under the action of extremes of heat and cold. The danger from lead is its strong affinity for sulphur, and the unfortunate fact that sulphide of lead is a blackish brown. Therefore when any of the colors containing sulphur (such as vermilion and the cadmiums) are mixed with either white lead or the chromes, we are sure to evolve the deadly sulphide, and there results a general browning or greening of the whole picture.
The rule, then, is either to content ourselves with zinc white, or, if white lead is used, to cast aside the cadmiums, vermilion, and emerald green (which, having a copper basis, is also subject to change when brought into contact with sulphur). The vermilion, fortunately, has now been replaced by the new color (which has been named by its makers Harrison red); and the cadmiums are hardly necessary, as they can be replaced by the chromes. Thus, with either lead white or zinc white, we have a very extended range, which has been greatly strengthened of late years by the addition of the two superb and perfectly safe alizarine colors, the scarlet and the crimson varieties. Neither the yellow nor the green alizarine can yet be claimed as perfectly sound and enduring; but then neither is essential.
Now, with this list of twenty or thirty pigments to select from, the question arises, naturally, as to the choice we shall make from them; for it is evident, I think, that even the most courageous amateur would hardly venture upon the whole gamut at one time. In the first place, it may be said that choice of palette is a matter of temperament. Each student must experiment with the various pigments and select those which he personally finds most sympathetic. But, in general, it is best to eliminate all the secondary or compound colors, such as green, purple, etc.; and this for two reasons: first, because a painter secures more vibration in his work by mixing his own secondary and tertiary tones; and, second, because if one has a green on the palette, one is very apt to use that special green, instead of searching out the various greens (and they are infinite) that may enter into his picture motive. It may also be stated as an axiom, that the more experienced the artist, the more limited is his palette. The expert cannot be bothered with useless pigments. He selects the few that are really essential and throws aside the rest as useless lumber. The distinguished Swedish artist, Zorn, uses but two colors—vermilion and yellow ochre; his two other pigments, black and white, being the negation of color. With this palette, simple to the point of poverty, he nevertheless finds it possible to paint an immense variety of landscape and figure subjects, and I have never heard his color criticised as being anæmic or lacking in power. Many other painters limit themselves to five colors; and when the palette is extended beyond seven, it is safe to presume that one is skirting the borders either of the amateur or the student class.
So much for pigments. But now we are confronted with another and a still more difficult problem: that of the medium in which the colors are to be mixed. For this purpose nothing better than pure linseed oil has ever been discovered, and indeed nothing better could be desired; for it combines nearly all of the good qualities—transparency, hardness, a certain flexibility when dry, and a durability whose limits we are as yet unable to gauge—the first pictures ever painted in oil colors being still in a good state of preservation. Unfortunately it has now become very difficult to obtain pure linseed oil. Most of the oil of the world is at present extractd by the oil trust, which, in order to secure a slightly increased output, subjects the seed under pressure to a high heat, with the result that in addition to the oil there is pressed out of the mash a variety of resins and essential oils, whose ultimate chemical effect on our colors we cannot as yet determine. Finally, the whole output is boiled with a certain addition of litharge to help its drying quality, and litharge is red lead. So here the lead equation enters into our palette again, in spite of our best efforts to exclude it. There are, however, I believe, two color-men in the world who, recognizing the necessity of pure raw oil for artist's use, have recently established plants of their own, where the seed is pressed cold and the oil is left raw. These firms are Bloch and Winsor & Newton. There may, of course, be others of which I do not know. To ensure entire safety and durability, nothing but pure linseed oil should be mixed with the colors; all cracking, gumming, etc., being due to inequalities in the drying period of the different mediums used on our canvas. If anything at all is mixed with the oil, the safest and best thing in the world is certainly pure Venice turpentine. If kerosene is used, it should be carefully washed to eliminate all of the acid which is used in refining the crude oil. Otherwise this free acid will attack the lead and discolor it.
In regard to varnishing, the important thing is to allow the picture to dry thoroughly before the varnish is applied. Six months is none too much for this, and a year is far better. A picture varnished before the oil is hard-dry is certain to crack sooner or later, as the oil and the varnish dry at different rates of speed. The pictures of Rubens and Vandyke were varnished with a medium made by exposing pure linseed oil to the sunlight until it was quite thick. This required a month or two to dry thoroughly after it was applied to the picture; but the splendid preservation and the great brilliancy of Rubens's pictures have justified all the extra pains and trouble incident to the method which he employed.