Field's Chromatography Part 20

229. RUBENS' MADDER,

_Orange Russet_, _Russet Rubiate_, or _Field's Russet_. This is a very rich crimson russet with a flush of orange; pure, transparent, and of a middle hue between orange and purple. Prepared from the madder root, it is not subject to change by the action of light, time, or mixture of other pigments. Although not so much employed as the marrone Madder Brown, it is serviceable both as a local and auxiliary colour in compounding and producing with yellow the glowing hues of autumnal foliage, &c.; and with blue, the beautiful and endless variety of grays in skies, flesh, &c. A good glazing colour, its thin washes afford fine flesh tints in water: as an oil pigment it dries indifferently, and requires to be forced by the addition of a little gold size or varnish.

Cappah brown and burnt umber sadden it to the rich tones adapted for general use in shadows. So saddened, this lake meets admirably the dark centres of the upper petals of certain fancy geraniums, while alone its pale washes are equally well suited to the lower leaves.

230. MIXED RUSSET.

What has been remarked in the preceding chapter upon the production of mixed citrine colours, is likewise applicable to mixed russet. By the immediate method of producing it materially from its secondaries, good and durable colours are obtained by compounding the following orange and purple pigments--

PERMANENT ORANGE. | PERMANENT PURPLE.

| Burnt Roman Ochre. | Mars Violet, true.

Burnt Sienna. | Purple Madder.

Cadmium Orange. | Mars Orange. | Neutral Orange. |

Many other less eligible duple and triple compounds of russet are obvious upon principle, and it may be produced by adding red in due predominance to some browns; but these, like most mixtures, are inferior to original pigments. To the orange colours there may be added cadmium red and the orange vermilions, pigments which were cla.s.sed among the reds, but which contain sufficient yellow to render them adapted for either compound russets or compound citrines. And as of original purple pigments there are two only which are stable, such mixtures as madder red and French blue will help to swell the list of available permanent purples. Rubens' madder itself may be changed in hue by being first mixed with blue and then with orange.

231. _Prussiate of Copper_

differs chemically from Prussian blue only in having copper instead of iron for its basis. It varies in hue from russet to purple brown, is transparent and deep, but, being very liable to change in colour by the action of light and by other pigments, has never been much used, and is now obsolete. The compound has the objection of containing free prussiate of potash, not removable by continued was.h.i.+ng--sometimes as much as five per cent.

There are several other pigments which enter imperfectly into, or verge upon, the cla.s.s of russet, which, having obtained the names of other cla.s.ses to which they are allied, will be found under other heads; such are some of the ochres, as Indian red. Burnt carmine is often of the russet hue, or convertible to it by due additions of yellow or orange; as are burnt Sienna and various browns, by like additions of lake or other reds.

The one pigment in this chapter known to the modern palette, Rubens'

madder, is permanent.

CHAPTER XVI.

ON THE TERTIARY, OLIVE.

Olive is the third and last of the tertiary colours, and nearest in relation to shade. Like its co-tertiaries, citrine and russet, it is composed of the three primaries, blue, red, and yellow; but is formed more directly of the secondaries, _purple_ and _green_, in each of which blue is a const.i.tuent: hence blue occurs twice in the latter mode of forming olive, while red and blue enter therein singly and subordinately. Blue is, therefore, in every instance the archeus or predominating colour of olive; its perfect or middle hue comprehending sixteen of blue to five of red and three of yellow. It partakes in a proportionate measure of the powers, properties, and relations of its archeus: accordingly, the antagonist or harmonizing contrast of olive is a _deep orange_. Like blue, olive is a retiring colour, the most so of all the colours, being the penultimate of the scale, or nearest of all in relation to black, and last, theoretically, of the regular distinctions of colours. Hence its importance in nature and painting is almost as great as that of black; it divides the office of clothing the face of creation with green and blue; with both which, as with black and grey, it enters into innumerable compounds and accordances, changing its name as either hue prevails, into green, gray, ashen, slate, &c. Thus the olive hues of foliage are called green, and the purple hues of clouds are called gray, &c.; but such terms are general only, and unequal to the infinite particularity of nature.

This infinity, or endless variation of hue, tint, and relation, of which the tertiaries are susceptible, gives a boundless license to the revelry of taste, in which the genius of the pencil may display the most captivating harmonies of colouring, and the most chaste and delicate expressions; too subtle to be defined, too intricate to be easily understood, and often too exquisite to be felt by the untutored eye.

Nature always melodizes by imperceptible gradations, while she harmonizes by distinct contrasts. At different seasons we have blossoms of all hues, variously subordinated; and when the time of flowers may be considered past, as if she had no further use for her fine colours, or were willing to display her ultimate skill and refinement, Nature lavishes the contents of her palette, not disorderly, but in multiplied relations, over all vegetal creation, in those rich and beautiful accordances of broken and finis.h.i.+ng colours with which autumn is decorated ere the year decays and sinks into olive darkness.

As a rule, no colour exists in nature without gradation, which is to colours what curvature is to lines. The difference in mere beauty between a gradated and ungradated colour may be seen by laying an even tint of rose-colour on paper, and putting a rose leaf beside it. The victorious beauty of the rose, as compared with other flowers, depends wholly on the delicacy and quant.i.ty of its colour gradations, all other flowers being either less rich in gradation, not having so many folds of leaf; or less tender, being patched and veined instead of flushed. It is not enough, however, that colour should be gradated in painting by being made simply paler or darker at one place than another. Generally, colour changes as it diminishes, and is not only darker at one spot, but also purer at one spot than elsewhere; although it does not follow that either the darkest or the lightest spot should be the purest. Very often the two gradations more or less cross each other, one pa.s.sing in one direction from paleness to darkness, another in another direction from purity to dulness; but there will almost always be both of them, however reconciled. Hence, every piece of blue, say, laid on should be quite pure only at some given spot, from which it must be gradated into blue less pure--greyish blue, or greenish blue, or purplish blue--over all the rest of the s.p.a.ce it occupies. In Turner's largest oil pictures, there is not one spot of colour as large as a grain of wheat ungradated; and it will be found in practice that brilliancy of hue, vigour of light, and even the aspect of transparency in shade, are essentially dependent on this character alone; hardness, coldness, and opacity, resulting far more from equality of colour than from nature of colour.

Given some mud off a city crossing, some ochre out of a gravel pit, a little whitening, and some coal-dust, and a luminous picture might be painted, if time were allowed to gradate the mud, and subdue the dust.

But not with the red of the ruby, the blue of the gentian, snow for the light, and amber for the gold, could such a picture be produced, if the ma.s.ses of those colours were kept unbroken in purity, and unvarying in depth.

Olive being usually a compound colour both with the artist and mechanic, there are few olive pigments in commerce.

232. MIXED OLIVE

may be compounded in several ways; directly, by mixing green and purple; or indirectly, by adding to blue a smaller proportion of yellow and red, or by breaking much blue with little orange. Cool black pigments, combined with yellow ochre, afford eligible olives; hues which are called _green_ in landscape, and _invisible green_ in mechanic painting.

It is to be noted that in producing these and other compound colours on the palette or canva.s.s, those mixtures will most conduce to the harmony of the performance which are formed of pigments otherwise generally employed in the picture. Thus, presuming aureolin to be the princ.i.p.al yellow used, the same yellow should be chosen for compounding orange and green, or for obtaining indirectly citrine, russet, and olive.

PERMANENT GREEN. | PERMANENT PURPLE.

| Oxide of Chromium, opaque. | Mars Violet, true.

Oxide of Chromium, transparent. | Purple Madder.

Veronese Green. | Viridian. | Emerald Green. | Scheele's Green. | Terre Verte. |

As in the case of russet, there may be added to the two original purples, mixtures composed of durable reds and blues. There are so many ways of producing the tertiaries, that no difficulty can be found in compounding them with stable pigments. Each tertiary may be represented as follows:--

CITRINE = Orange + Green.

" = (Yellow + Red) + (Yellow + Blue.) " = 2 Yellow + Red + Blue.

RUSSET = Orange + Purple.

" = (Yellow + Red) + (Red + Blue.) " = 2 Red + Yellow + Blue.

OLIVE = Green + Purple.

" = (Yellow + Blue) + (Red + Blue.) " = 2 Blue + Yellow + Red.

From the above equations, and by consulting the lists given of permanent primary and secondary colours, the artist will at once see how easily and safely he may vary his mode of compounding the tertiaries.

233. OLIVE GREEN,

sometimes called _Dewint's Green_, is an arbitrary compound, or mixed green, of a fine deep olive colour and sober richness. Advisedly or not, it is used in landscape, sketching, &c.; but only in water, olive lake supplying its place in oil. Like many other compound pigments, it is either permanent, semi-stable, or fugitive, according to the const.i.tuents of which it is composed. Generally speaking, it is more beautiful than durable, and is often decidedly fugacious, fading on exposure. It is impossible for a writer to p.r.o.nounce an absolute opinion on the stability of all mixtures sold in a separate form, inasmuch as the compounds of one firm may differ from those of another. We have before expressed our dislike to such pigments, and this uncertainty with regard to their composition serves to strengthen it. Nevertheless, as there are exceptions to every rule, it must be admitted that the palette possesses compounds always to be relied upon.

234. OLIVE LAKE

is in commerce exclusively an oil colour. When true, it is a lake prepared from the green ebony, or laburnum, and is of considerable permanence, transparency, and depth, both in water and oil; in which latter vehicle it dries well. This variety, however, may be said to be obsolete; having given way to a mixture, usually semi-stable, and liable to blacken.

235. _Burnt Verdigris_

is what its name expresses, and is an olive-coloured oxide of copper deprived of acid. It dries remarkably well in oil, is more durable than the original verdigris, and is in other respects an improved and more eligible pigment, although not to be recommended.

236. _Olive Oxide of Chromium._

An olive oxide of this metal is obtainable, transparent, of strict stability, and altogether superior to any original or compound olive pigment as yet known. Eligible either in water or oil, it is admirably adapted for autumn foliage, where a quiet, subdued, nature-like green is required. It has not, however, been introduced, partly because of its expense, and partly because a mixture of other pigments with the ordinary chrome oxides sufficiently answers the purpose. There are more good colours in the world than are dreamt of in the palette's philosophy, but either they are not wanted, or are too costly to sell.

In a great measure, both art and science are dependent on commerce.

237. _Olive Rinman's Green._

A compound a.n.a.logous to cobalt green may be made, of an olive hue, with more body, and equally stable.

238. _Olive Scheele's Green._

Cupric a.r.s.enite, when heated, gives off a.r.s.enious acid and water, leaving a residue of a.r.s.enide of copper and copper a.r.s.eniate. A series of olive colours is so afforded, which are as durable as their original pigment, and might with advantage be subst.i.tuted for the doubtful compounds at present in use.

239. _Olive Schweinfurt Green_