Under the names of English Green, Green Cinnabar, &c., 'new' green pigments have been from time to time introduced, which have turned out mixtures of Prussian blue and chromate of lead; not made, however, by compounding the two, but directly by processes similar to the following:—A mixed solution of the acetates of lead and iron is added to a mixed solution of the yellow prussiate and chromate of potash, the necessary acetate of iron being obtained by precipitating a solution of acetate of lead by sulphate of iron, and filtering the supernatant liquid. Or; to a solution of Prussian blue in oxalic acid, first chromate of potash is added, and then acetate of lead.

By the last process, superior and more permanent chrome greens may be produced, free from lead, by using chloride of barium or nitrate of bismuth in place of the acetate of lead. Chromate of baryta, or chromate of bismuth is then formed, neither of which acts on the Prussian blue.

It should be added that where the latter pigment is present, no green will serve for painting walls containing lime, as its action alters the tint of the Prussian blue.

186. HOOKER'S GREEN

is a compound of Prussian blue and gamboge, two pigments possessing a like degree of stability, and perfectly innocuous to each other. It is a mixture more durable and more transparent than chrome greens made with chromate of lead. There are two varieties in common use—No. 1, a light grass green, in which the yellow predominates; and No. 2, a deeper and more powerful green, with a larger amount of blue.

187. PRUSSIAN GREEN,

like the preceding, is composed of Prussian blue and gamboge; but contains a very great excess of the former, and is therefore a bluish-green of the utmost depth and transparency, verging on black in its deep washes. Yellow ochre may be employed instead of gamboge, but is not so eligible.

A true Prussian green, which has been recommended as a pigment, can be produced as a simple original colour, with a base wholly of iron. It is got by partially decomposing the yellow oxalate of protoxide of iron with red prussiate of potash. We have made this green and given it a fair trial, but our verdict is decidedly against it. In colour it is far from being equal to a good compound of Prussian blue and gamboge, and it assumes a dirty buff-yellow on exposure to light and air, the film of blue on the oxalate more or less disappearing.

Another Prussian green, with a base of cobalt, is obtained by precipitating the nitrate of that metal with yellow prussiate of potash. According to the mode adopted, and the degree of heat, either a light or dark green results; but this also is inferior in colour, and presents no advantage as to permanence.

188. SAP GREEN,

Verde Vessie, or Iris Green, is a vegetal pigment prepared from the juice of the berries of the buckthorn, the green leaves of the woad, the blue flowers of the iris, &c. It is usually preserved in bladders, and is thence sometimes called Bladder Green. When good, it is of a dark colour and glossy fracture, extremely transparent, and a fine natural yellowish green. This gummy juice, inspissated and formed into a cake, is occasionally employed in flower painting. It is, however, a very imperfect pigment, disposed to attract the moisture of the atmosphere, and to mildew; while, having little durability in water and less in oil, it is not eligible in the one and is totally useless in the other.

Similar pigments, obtained from coffee-berries, and named Venetian and Emerald Greens, are of a colder colour, equally defective and fugitive, and now obsolete.

189. TERRE VERTE,

or Green Earth, is a sober bluish green with a grey cast. It is a species of ochre, containing silica, oxide of iron, magnesia, potash, and water. Not bright and of little power, it is a very durable pigment, being unaffected by strong light or impure air, and combining with other colours without injury. It has not much body, is semi-transparent, and dries well in oil. Veins of brownish or reddish ochre are often found mixed with terre verte, to the detriment of its colour; and there are varieties of this pigment with copper for their colouring matter, which, although generally brighter, are inferior in other respects, and not true terre vertes. Verona Green and Verdetto or Holy Green, are ferruginous native pigments of a warmer hue. These are met with in the Mendip Hills, France, Italy, and the island of Cyprus, and have been used as pigments from the earliest times. Rubens has availed himself much of terre verte, not in his landscapes merely, but likewise in the carnation tints in his figures of a dead Christ. It is evident that much of the glazing is done with this colour: it is, in fact, most useful in glazing; because, having only a thin substance, it can be rendered pale by a small portion of white; although in the end it becomes darker by a concentration of its molecules. Mrime states that in the greater part of Alexander Veronese's works—in his Death of Cleopatra, in the Louvre, for instance—there are some demi-tints which are too green, and which it is certain were not so originally. Terre verte, therefore, must be employed with caution; and it would be well to ascertain beforehand whether a mineral colour will in time become darker than when first laid on the picture, by putting a drop of oil on the powder in its natural state. If the tone this gives to it be more intense than that which it acquires by being ground up, it may fairly be assumed that it will attain to the same degree of strength whenever, having completely dried, its molecules shall have re-united as closely as it is possible. Umber and terra di Sienna are of this class.

In combination with Indian red and Naples yellow, terre verte forms a series of mild russet greens, of much use in middle distance.

* * * * *

190. Chrome Arseniate

is an agreeable apple-green colour, prepared from arseniate of potash and salts of chromic oxide. It is durable, but possesses no advantages over the chrome oxides, and is of course poisonous.

191. Cobalt Green,

Rinman's Green, Vert de Zinc or Zinc Green. True cobalt green is made by igniting a very large quantity of carbonate of zinc with a very small quantity of carbonate of cobalt. To give a green tint to an enormous proportion of the former, an inappreciable amount of the latter will suffice. Some samples which were analysed, consisted almost entirely of zinc, there being only two or three per cent. of cobalt present. This green presents an example of a pigment being chemically good and artistically bad, or at least indifferent. It is a moderately bright green, apt to vary in hue according to the mode of manufacture, permanent both alone and compounded, but so sadly deficient in body and power, as to have become almost obsolete. With other physical defects, and a colour inferior to the chrome oxides, cobalt green has never been a favourite with artists, though justly eulogised by chemists.

192. Copper Borate

is obtained by precipitating sulphate of copper with borax, washing the residue with cold water, and, after drying, igniting it, fusion being carefully avoided. In this manner, a pretty yellowish green is produced, which upon longer ignition assumes a dark green shade: the mass is levigated for use. The compound has the objection of being glassy, and possessing little body, but is preferable to verdigris as to permanence.

193. Copper Chrome

may be prepared by several methods, but the colour is in no case so fine as Scheele's or Schweinfurt green, nor is it as stable.

194. Copper Stannate,

or Tin-Copper Green, equals in colour any of the copper greens free from arsenic. The cheapest way of making it is to heat 59 parts of tin in a Hessian crucible with 100 parts nitrate of soda, and dissolve the mass when cold in a caustic alkali. To the clear solution, diluted with water, a cold solution of sulphate of copper is added: a reddish-yellow precipitate falls, which on being washed and dried, becomes a beautiful green. On the palette it would be superfluous, but for common purposes might be found of service.

195. Elsner's Green

is also a combination of tin and copper. It is made by adding to a solution of sulphate of copper a decoction of fustic, previously clarified by a solution of gelatine. To this mixture are added ten or eleven per cent. of protochloride of tin, and lastly an excess of caustic potash or soda. The precipitate is then washed and dried, whereupon it takes a green colour tinged with blue, but without the brightness or durability of the preceding stannate.

196. Green Bice,

or Green Verditer, is the same in substance as blue verditer, which is converted into green verditer by boiling. This pigment is one of the least eligible of copper greens.

197. Green Ochre.

By partially decomposing yellow ochre with prussiate of potash, we have produced a fine dark blue-green, resembling Prussian green, of great depth and transparency. There are, however, difficulties in the process; and the results do not warrant us in pronouncing this green superior or equal to a mixture of the ochre and Prussian blue.

198. Green Ultramarine

is French or artificial ultramarine before the final roasting. It is a somewhat bright bluish-green, becoming a dull greenish-blue on continued exposure. Chemically, it is not a bad colour; but artists generally have decided against it.

199. Manganese Green,

or Cassel Green. By several methods, manganate of baryta may be obtained either as an emerald-green, a bluish-green, or a pale green. The manganates, however, are decomposed by contact with organic matter; and hence the green would be liable to suffer from the vehicles employed, as well as by being compounded with animal or vegetal pigments.

200. Mineral Green

is the commercial name of Green Lakes, prepared from sulphate of copper. These vary in hue and shade, have all the properties of the common non-arsenical copper-greens, and, not being subject to change of colour by oxygen and light, stand the weather well, and are excellent for the use of the house-painter, &c. Having a tendency to darken and blacken by time and foul air, they are not eligible in the nicer works of fine art.

Another Mineral Green adopted in Germany as a substitute for the poisonous Schweinfurt green, is composed of chromate of lead, carbonate of copper, oxide of iron, and chalk. Valueless for the palette, it has not the beauty of Schweinfurt green, but is recommended as being free from arsenic. It is not, however, altogether harmless, and should not be used in confectionery or the like.

201. Molybdenum Green.

A clear malachite green colour, when dried, is produced from molybdate of soda and potash-chrome-alum, or from the molybdate and alum with ammonia. Being more expensive than the chrome oxides and not better, its introduction, for use by artists, would be attended with no advantage.

There is likewise obtainable a copper molybdate, by adding neutral molybdate of soda in excess to sulphate of copper. The precipitate is a very pale green colour, flocculent at first, but crystalline after washing. Like the chrome molybdate it would be superfluous as a pigment.

202. Quinine Green

is rather adapted for a dye than an artist-colour. It is furnished by acting on quinine with hypochlorite of lime, hydrochloric acid, and ammonia, successively. Thus prepared, the green resembles a resin, insoluble in water, but soluble in alcohol, and turned blue by acetic acid. Its alcoholic solution dyes silk green, and also woollen and cotton when mordanted with albumen.

203. Roman Green,

brought from Rome some years back by a President of the Royal Academy, appeared to be a mixture of Prussian blue and Dutch or Italian pink. It was a fugitive compound, which became blue in fading.

204. Silicate of Baryta.

One part of silica heated to whiteness with three parts of baryta, yields a pale green solid mass, permanent, but deficient in colour when ground. It might be employed in enamelling.

205. Titanium Green

has been proposed as a substitute for the green arsenical pigments in common use; but, apart from its expense, the colour is very inferior to Scheele's green, &c. Titanium green is a ferrocyanide of that metal, produced by adding yellow prussiate of potash to a solution of titanic acid in dilute hydrochloric acid, and heating the mixture to ebullition rapidly. The dark green precipitate is washed with water acidulated with hydrochloric acid, and dried with great care, since it decomposes at temperatures above 100.

206. Uranium Green

is an oxide of a deep dull green colour, inclining to olive, and nearly black when in lumps. A durable but unattractive preparation, equalled in permanence and far surpassed in beauty by many cheaper compounds.

207. Vanadium Green

falls when ferrocyanide of potassium is added to vanadic acid dissolved in a strong acid. It is a beautiful green precipitate, but at present simply a curiosity, owing to the rarity of the metal vanadium.

* * * * *

Adopting our usual custom of separating the wheat from the chaff, we point to the opaque and transparent oxides of chromium, Veronese green, viridian, emerald green, Scheele's green, and terre verte, as more or less worthy of being dubbed durable.

As semi-stable, malachite green, bronze, Hooker's green, and Prussian green, must be classed.

Verdigris, chrome greens, and sap green, should be branded as fugitive: the chrome greens, because they are always commercially composed of chromate of lead and Prussian blue, two compounds which are semi-stable in themselves, but become fugacious when compounded.

A reference to the numbered italicised greens will show that there are many not known to the palette, which are nevertheless very greatly superior, as regards permanence, to some that disgrace it. Why these latter are suffered to hold their position is a mystery not easily explained: it is hard to reconcile the deplored degeneracy of modern pigments with the popularity of semi-stable and fugitive colours. Pictures do not stand, is the common cry; therefore, says the public, there are no good pigments now-a-days. To which we answer, newly built houses are constantly falling down; therefore there are no good bricks in these times. Of a truth, one conclusion is as reasonable as the other: in either case, if rotten materials be used, the result cannot be lasting; but in neither case does it follow, because such materials are employed, that there are no better obtainable. A well-built house implies a conscientious builder, and a well-painted picture implies a conscientious artist. It is because, we fear, that there are so few conscientious artists, that there are so few permanent paintings; not, certainly, because there are no good pigments. In this last belief, however, the public is encouraged by certain painters, who seek thereby to excuse their own shortcomings, forgetting that it is a bad workman who finds fault with his tools. It has been well observed that when artists speak regrettingly of lost 'systems,' or pigments enjoyed by the medivalists and unattainable now, it would be far better were they to make the best use of existing materials, and study their further development. There is no need for this cant cry of fugacity, which casts such a blight on modern art. Durable pigments are not yet obsolete, they have only to be employed and employed properly to furnish paintings equal in permanence to those of the old masters. "Titian," says Haydon, "got his colours from the colour shops on the Rialto, as we get ours from Brown's; and if Apelles or Titian were living now, they would paint just as good works with our brushes and colours as with their own."



CHAPTER XIII.

ON THE SECONDARY, PURPLE.

Purple, the third and last of the secondary colours, is composed of red and blue, in the proportions of five of the former to eight of the latter; proportions which constitute a perfect purple, or one of such a hue as will neutralize and best contrast a perfect yellow, in the ratio of thirteen to three, either of surface or intensity. When mixed with its co-secondary colour, green, purple forms the tertiary olive; and, when compounded with the remaining secondary, orange, it constitutes in like manner the tertiary russet. Of the three secondary colours it is the coolest, as well as the nearest in relation to black or shade; in which respect, and in never being a warm colour, it resembles blue. In other respects also, purple partakes of the properties of blue, which is its archeus, or ruling colour; hence it is to the eye a retiring colour, that reflects light little, and loses rapidly in power in a declining light, and according to the distance at which it is viewed. By reason of its being the mean between black and blue it becomes the most retiring of all positive colours. Nature employs this hue beautifully in landscape, as a sub-dominant, in harmonizing the broad shadows of a bright sunshine ere the light sinks into deep orange or red. Girtin, who saw Nature as she is, and painted what he saw, delighted in this effect of sunlight and shadow. As a ruling colour, whether in flesh or otherwise, purple is commonly too cold, or verges on ghastliness, a fault which is to be as much avoided as the opposite extreme of viciousness in colouring, stigmatized as foxiness.

Yet, next to green, purple is the most generally pleasing of the consonant colours; and has been celebrated as a regal or imperial colour, as much perhaps from its rarity in a pure state, as from its individual beauty. Romulus wore it in his trabea or royal mantle, and Tullus Hostilius, after having subdued the Tuscans, assumed the pretexta or long robe, broadly striped with purple. Under the Roman emperors, it became the peculiar emblem or symbol of majesty, and the wearing of it by any who were not of the Imperial family, was deemed a "treasonable usurpation," punishable by death. At the decline of the empire, the Tyrian purple was an important article of commerce, and got to be common in the clothing of the people. Pliny says, "Nepos Cornelius, who died in the reign of Augustus Csar, when I was a young man, assured me that the light violet purple had been formerly in great request, and that a pound of it usually fetched 100 denaria (about 4 sterling): that soon after the tarentine or reddish purple came into fashion; and that this was followed by the Tyrian dibapha, which could not be bought for less than 1000 denaria (nearly 40 sterling) the pound; which was its price when P. Lentulus Spinter was dile, Cicero being then Consul. But afterwards, the double-dyed purple became less rare, &c." The Tyrian purple alluded to was obtained from the purpur, a species of shell-fish adhering to rocks and large stones in the sea adjoining Tyre. On account, probably, of its extreme costliness, it was frequently the custom to dye the cloth with a ground of kermes or alkanet, previous to applying the Tyrian purple. This imparted to the latter a crimson hue, and explains doubtless the term, double-dyed. The Greeks feigned the ancient purple to be the discovery of Hercules Tyrius, whose dog, eating by chance of the fish from which it was produced, returned to him with his mouth tinged with the dye. Alexander the Great is said to have found in the royal treasury, at the taking of Susa, purple to the enormous value of 5000 talents,[A] which had lain there one hundred and ninety-two years, and still preserved its freshness and beauty.

When inclining to red, purple takes the name of crimson, &c.; and when leaning to blue, the names of violet, lilac, mauve, &c. Blue is a colour which it serves to mellow, or follows well into shade. The contrast or harmonizing colour of purple is yellow on the side of light and the primaries; while purple itself is the harmonizing contrast of the tertiary citrine on the side of shade, and less perfectly so of the semi-neutral brown. As the extreme primaries, blue and yellow, when either compounded or opposed, afford, though not the most perfect harmony, yet the most pleasing consonance of the primary colours; so the extremes, purple and orange, yield the most pleasing of the secondary consonances. This analogy extends likewise to the extreme tertiary and semi-neutral colours, while the mean or middle colours furnish the most agreeable contrasts or harmonies.

In nature pure purple is not a common colour, and on the palette purple pigments are singularly few. They lie under a peculiar disadvantage as to apparent durability and beauty of colour, owing to the neutralizing power of yellowness in the grounds upon which they are laid; as well as to the general warm colour of light, and the yellow tendency of almost all vehicles and varnishes, by which the colour of purple is subdued.

208. BURNT CARMINE

is the carmine of cochineal partially charred till it resembles in colour the purple of gold, for which, in miniature and water-painting, it is substituted. It is a magnificent reddish purple of extreme richness and depth, eligible in flower-painting and the shadow of draperies. As it is generally impossible, however, to alter the nature of a pigment by merely changing its colour, burnt carmine is scarcely more permanent than the carmine from which it is produced. If used, therefore, it should be in body, and not in thin washes or as a glaze. Durable pigments are admissible in any form; but semi-stable pigments (gamboge excepted) should only be employed in body.

209. BURNT LAKE

holds the same relation to crimson lake as burnt carmine to ordinary carmine; and is hence a weaker variety of the preceding, with less richness, and likewise less permanence.

210. INDIAN PURPLE

is prepared by precipitating an extract of cochineal with sulphate of copper. It is a very deep-toned but rather cold and subdued purple, neither so red nor so brilliant as burnt carmine; and is chiefly of service in draperies. It is apt to lose its purple colour in a great measure on exposure to light and air, and assume an inky blackness; a defect which becomes less apparent when the pigment is used in bulk.

211. MARS VIOLET,

Violet de Mars, Purple Ochre, or Mineral Purple, is a dark ochre, native of the Forest of Dean in Gloucestershire. It is of a murrey or chocolate colour, and forms cool tints of a purple hue with white. It is of a darker colour than Indian red, which has also been classed among purples, but has a similar body and opacity, and generally resembles that pigment. It may be prepared artificially, and some natural red ochres burn to this colour. Being difficult and sometimes impossible to procure, Mars violet is often compounded; in which case it is liable to vary both in hue and stability. As, however, Indian red is always taken for its basis, the mixture is never wholly fugitive, nor exhibits any very glaring contrast on exposure.

212. MIXED PURPLE.

Purple being a secondary colour, composed of blue and red, it follows of course that any blue and red pigments, which are not chemically at variance, may be employed in producing mixed purples of any required hue, either by compounding or grinding them together ready for use, or by combining them in the various modes of operation in painting. In such compounding, the more perfect and permanent the original colours are, the more perfect and permanent will be the purple obtained. To produce a pure purple, neither the red nor the blue must contain or incline to yellow; while to compound a durable purple, both the red and the blue must be durable also. Ultramarine and the reds of madder yield beautiful and excellent purples, equally stable in water or oil, in glazing or tint, whether under the influence of light or impure air. Cobalt blue and madder red likewise afford good purples; and some of the finest and most delicate purples in ancient paintings appear to have been composed of ultramarine and vermilion, which furnish tints equally permanent, but less transparent than the above, and less easily compounded. Facility of use, and other advantages, are obtained at too great a sacrifice by the employment of perishable mixtures, such as the lakes of cochineal with indigo.

PERMANENT REDS. PERMANENT BLUES. Cadmium Red. Cerulian Blue. Liquid Rubiate. Cobalt Blue. Madder Carmine. Genuine Ultramarine. Rose Madder. Brilliant Ultramarine. Mars Red. French Ultramarine. Ochres. New Blue. Vermilions. Permanent Blue.

It should be noted that all the above reds do not afford pure purples with blue; those which contain more or less yellow, as cadmium red and orange vermilion, furnish purples partaking more or less of olive, which is a compound of purple and green. To those reds may be added the russet Rubens Madder and the marrone Madder Brown, two pigments which are alike eligible for mixed purple and mixed orange. No purple, it will be remarked, equal in gorgeous richness to that produced from crimson lake and Prussian blue is obtainable from the colours given; just as no mixed green is of such depth and power if that blue be wanting as a constituent. But, as our compound tints are given rather as examples of durability than beauty, all semi-stable or fugitive mixtures are of necessity ignored.

213. PURPLE MADDER,

Field's Purple, or Purple Rubiate, is the only durable organic purple the palette possesses. Marked by a soft subdued richness rather than by brilliancy, it leans somewhat towards marrone, and affords the greatest depth of shadow without coldness of tint. Unfortunately, in the whole range of artistic pigments there is no colour obtainable in such small quantity as madder purple; hence its scarcity and high price cause it to be confined to water-colour painting, in which the clearness and beauty of its delicate tones render it invaluable in every stage of a drawing. With raw Sienna and indigo or Prussian blue, subdued by black, it gives beautiful shadow tints, and will be found useful in sky and other effects compounded with cobalt, rose madder, French blue and sepia, yellow ochre and cobalt, lamp black and cobalt, light red, Vandyke brown, burnt Sienna, or aureolin. With great transparency, body, and depth, it is pure and permanent in its tints, neither gives nor sustains injury on admixture, dries and glazes well in oil, works well, and is altogether most perfect and eligible. For fresco it is admirably adapted, being quite uninjured by lime.

There is a lighter and slightly brighter sort, containing less colouring matter and more base, which has all the properties of the above with less intensity of colour. For the sake of cheapness, the purple is sometimes compounded in oil, generally of brown madder and a blue. Provided the latter be stable, transparent, and mix kindly, no greater objection can be taken to this than to the neutral orange of brown madder and yellow ochre.

214. VIOLET CARMINE

is a brilliant bluish purple of much richness, employed in draperies and the like. It is prepared by precipitating an alcoholic extract of the root of the Anchusa tinctoria, commonly known as alkanet, a plant growing in the Levant, and some other warm countries. It was used by the ancients as a dye, or as a groundwork to those stuffs which were to be dyed purplish-red: the ladies in ancient times also employed it as a paint. Its colouring matter or anchusin has the character of a resin, and is dark-red, softened by heat, insoluble in water, soluble in alcohol and alkalis, and freely so in ether, fats, and volatile oils, to all of which it imparts a brilliant red hue. To obtain anchusin, all the soluble matters are first abstracted from the bruised root by water: it is then digested in a solution of carbonate of potash, from which it may be readily precipitated by an acid. Its alcoholic solution yields with different reagents crimson, flesh-coloured, blue, and violet precipitates, none of which, however, can be classed as durable. The variety under notice, violet carmine, resembles the other colours afforded by alkanet in not being able to withstand the action of light. On continued exposure, it loses its beauty and brightness, together with much of its colour, and, like Indian purple, assumes an inky blackness. Hence it is unsuited to permanently pure effects, and should only be used in body.

* * * * *

215. Archil Purple.

Archil may be regarded as the English, cudbear as the Scotch, and litmus as the Dutch name for one and the same substance, extracted from several species of lichens by various processes. These lichens, which are principally collected on rocks adjacent to the sea, are cleaned and ground into a pulp with water, treated from time to time with ammoniacal liquor, and exposed with frequent agitation to the action of the atmosphere. Peculiar principles existing in the lichens are, by the joint instrumentality of the air, water, and ammonia, so changed as to generate colouring matter, which, when perfect, is expressed. Soluble in water and alcohol, this colouring principle yields by precipitation with chloride of calcium a compound known as 'Solid French Purple', a pigment more stable than the archil colours generally, but all too fugitive for the palette.

216. Bismuth Purple.

A purple powder is capable of being produced from bismuth by passing chlorine gas through the hydrated oxide suspended in a saturated solution of potash. As soon as the oxide becomes brown-red, the mixture is boiled and the liquid decanted off at once, the residue being immediately washed first with alcohol and then with water. On the whole, the result is not, for an artistic pigment, worth the trouble involved in the preparation.

217. Burnt Madder

is obtained by carefully charring madder carmine until it becomes of the hue required. Bearing the same relation to madder carmine as burnt carmine to the carmine of cochineal, burnt madder is a permanent and perfectly unexceptionable pigment. By reason, probably, of its great price, it is not mentioned in trade catalogues, and must be held as commercially unknown.

218. Cobalt Purples

are obtainable ranging from the richest crimson purple to the most delicate violet. We have produced them by wet and dry methods, varying in brilliancy and beauty, but characterised generally by want of body, and frequently by a smalt-like grittiness. Chemically, good and stable colours, they are not received with favour on the palette, and certainly may be very well replaced by mixtures of cobalt blue and madder red. When a permanent compound is obtainable equal in colour to an original pigment, and superior in its physical attributes, no objection can fairly be taken to its artistic preference. There are other things to be considered in a pigment besides permanence, or even permanence and colour combined. The two together do not constitute a perfect pigment, that is, a material of practical utility and value. In the last chapter, allusion was made to a green which possesses both the one and the other, and yet is—at present, at least—quite unfitted for artistic use. Hence, with a strong partiality for simple original pigments, we are bound to confess there are cases where mixtures are justifiably preferred. All we contend for is, that each constituent of such mixtures should be stable, and neither give nor receive injury by being compounded.

219. Gold Purple,

Purple of Cassius, or Cassius's Purple Precipitate, was discovered in 1683 by Cassius of Leyden. It is a compound of tin and gold, best formed by mixing aqueous perchloride of iron with aqueous protochloride of tin, till the colour of the liquid has a shade of green, and then adding this liquid, drop by drop, to a solution of perchloride of gold, which is free from nitric acid and very dilute: after twenty-four hours the purple is deposited. When recently prepared, the colour is brightened by boiling nitric acid. Not brilliant, but rich and powerful, this purple varies in hue according to the mode of manufacture from deep crimson to murrey or dark purple: it also differs in degrees of transparency. Working well in water, it is an excellent though costly pigment, once popular in miniatures, but at present rarely, if ever used, as purple madder is cheaper, and perfectly well supplies its place. Retaining its colour at a high red heat, it is now confined to enamel and porcelain painting, and to tinging glass of a fine red. If, whilst in its hydrated state, it be washed with ammonia, a bright purple liquid results, from which a violet colour, somewhat less expensive, can be produced, by combining the gold purple with alumina, and calcining the product in the same way that is practised with cobalt. This compound may be exposed to the action of the sun's rays for a year without being sensibly affected.

220. Prussian Purple.

A prussiate of iron is obtainable of a violet hue, affording good shadow tints and clear pale washes. It has not, however, been introduced as a pigment, as ordinary Prussian blue tinged with red furnishes a similar colour.

221. Sandal Wood Purple.

Sandal wood contains about 16 per cent. of colouring matter, soluble with difficultly in water, but readily dissolved by alcohol. From the latter solution, chloride of tin throws down a purple, and sulphate of iron a deep violet precipitate; neither of which is remarkable for permanence.

222. Tin Violet.

By heating chromate of stannic oxide to bright redness, a dark violet mass is obtained, which is better adapted to enamel painting than to the palette. It communicates in glazings a variety of tints, from rose-red to violet.

* * * * *

So scant is the number of good purples in common use, that there are but two which can be classed as durable, namely, purple madder and the true Mars violet.

Foremost in the second group stands burnt carmine. As there are different degrees both of permanence and fugacity, so are there different degrees of semi-stability. Burnt carmine, burnt lake, Indian purple, and violet carmine, all belong to this division; but the first certainly is more permanent than the rest.

Rich and beautiful as it is, purple madder cannot be called brilliant; while Mars violet is, of course, ochrous. Unlike green and orange, therefore, purple can point to no original pigment at once vivid and durable: as regards purple, brilliancy implies a semi-stability that borders more or less closely on fugacity. Until the advent of a perfect palette, however, brilliancy and semi-stability will doubtless hold their own. Their present popularity may be seen by a glance at the lists of artist-colours—lists compiled, be it remembered, in obedience to the law of demand and supply. If art were really so much honoured as some of its disciples pretend, none but durable colours would be employed. In our opinion, if a picture be worth painting at all, it is worth painting with permanent pigments; but many evidently think otherwise. Deploring an error neither flattering to the craft they practise nor to themselves, we would urge such to bear in mind this axiom, semi-stable pigments become fugitive when used in thin washes. Even in body they do not preserve their primitive hue, but in glazing and the like, their colour altogether flies or is wholly destroyed.

It is this semi-stability, recommended to the thoughtless and indifferent by the beauty which generally accompanies it, that is the bane of modern art. Even our greatest painters have yielded to its fascination. Who has not gazed upon one of Turner's fading pictures with still more of sadness than enjoyment, that anything so grand, so beautiful, so true, should slowly but surely be passing away? A feeling akin to pity is conjured up at the sight of the helpless wreck, abandoned amid the treacherous materials employed, and sinking deeper and deeper. Mournful, indeed, is that mighty ruin of mind amid matter; mournful the thought that in years to come, the monument sought for will not be found.

FOOTNOTES:

[A] A talent of money, i.e., a talent's weight of silver, was equal to nearly 244.



CHAPTER XIV.

ON THE TERTIARY, CITRINE.

Citrine, or the colour of the citron, is the first of the tertiary class of colours, or ultimate compounds of the primary triad, yellow, red, and blue; in which yellow is the archeus or predominating colour, and blue the extreme subordinate. For citrine being an immediate compound of the secondaries, orange and green, of both which yellow is a constituent, the latter colour is of double occurrence therein, while the other two primaries enter singly into its composition. The mean or middle hue comprehends eight blue, five red, and six yellow, of equal intensities.

Hence citrine, according to its name, which is that of a class of colours and used commonly for a dark yellow, partakes in a subdued degree of all the powers of its archeus yellow. In estimating, therefore, its properties and effects in painting, it is to be regarded as participating of all the relations of yellow. By some this colour is improperly called brown, as almost all broken colours are. The harmonizing contrast of citrine is a deep purple, which may be seen beautifully opposed to it in nature, when the green of summer declines. As autumn advances, citrine tends towards its orange hues, including the colours termed aurora, chamoise, and others before enumerated under the head of yellow. It is the most advancing of the tertiary colours, or nearest in relation to light; and is variously of a tender, modest, cheering character.

To understand and relish the harmonious relations and expressive powers of the tertiary colours, require a cultivation of perception and a refinement of taste for which study and practice are needed. To a great extent the colourist, like the poet, is born not made; but although he must have an innate sense of the beautiful and the true, hard work alone, with his head, his eyes, and his hands, will enable him to learn and turn to account the complex beauties and relations of tertiary colours. They are at once less definite and less generally evident, but more delightful—more frequent in nature, though rarer in common art, than the like relations of the secondaries and primaries. There is very little pure colour in the world: now and then a gleam dazzles us, like a burst of sunshine through grey mists; but as a rule, nature prefers broken colours to absolute hues. Most pure in spring, most full in summer, most mellow in autumn, most sober in winter, her tints and shades of colour are always more or less interlaced, from white and the primaries to the semi-neutral and black.

Of original citrine-coloured pigments there are only a few, unless we include several imperfect yellows which might not improperly be called citrines. The following are best entitled to this appellation:—

223. BROWN PINK,

Brown Stil de Grain, Citrine Lake, or Quercitron Lake is usually prepared from the berries of Avignon (ramnus infectorius), better known as French, Persian, or Turkey berries; but a more durable and quicker drying species is obtained from the quercitron bark. If produced from the former, it must be branded as fugitive, but if from the latter, it may be termed semi-stable. In either case it is a lake, precipitated from the alkaline decoction by means of alum, in such proportions that the alkali shall not be more than half saturated. The excess of soda or potash employed imparts a brown hue; but the lake being in general an orange broken by green, falls into the class of citrine colours, sometimes inclining to greenness, and sometimes towards the warmth of orange. It works well both in water and oil, in the latter of which it is of great depth and transparency, but its tints with white lead are very fugitive, and in thin glazing it does not stand: the berry variety dries badly. A fine rich colour, more beautiful than eligible, it is popular in landscape for foliage in foregrounds. Modified by admixture with burnt Sienna or gamboge, it yields a compound which, with the addition of a small quantity of indigo, gives a warm though not very durable green. In many of the Flemish pictures the foliage has become blue from the yellowish lake, with which the ultramarine was mixed, having faded.

It has been remarked that the alteration made by time in semi-stable pigments is not so observable when they are employed in full body. Their use generally has been deprecated, but in shadows such vegetable colours as brown pink are sometimes of advantage, as they are transparent, lose part of their richness by the action of the air, and do not become black. Moreover, if mixed with pigments which have a tendency to darken, they mitigate it very much. This last, indeed, is the most legitimate purpose to which semi-stable pigments whose colour fades on exposure can be put.

224. MARS BROWN,

or Brun de Mars, is either a natural or artificial ochre containing iron, or iron and manganese. Of much richness and strict permanence, it resembles raw umber in being a brown with a citrine cast, but is generally marked by a flush of orange which is not so observable in the latter pigment.

225. MIXED CITRINE.

What has been before remarked of the mixed secondary colours is more particularly applicable to the tertiary, it being more difficult to select three homogeneous substances of equal powers as pigments than two, that shall unite and work together cordially. Hence the mixed tertiaries are still less perfect and pure than the secondaries; and as their hues are of extensive use in painting, original pigments of these colours are proportionably estimable to the artist. Nevertheless there are two evident principles of combination, of which he may avail himself in producing these colours in the various ways of working; the one being that of combining two original secondaries; and the other, of uniting the three primaries in such a manner that the archeus shall predominate. Thus in the case of citrine, either orange and green may be directly compounded; or yellow, red, and blue be so mixed that the yellow shall be in excess.

These colours are, however, obtained in many instances with best and most permanent effect, not by the intimate combination of pigments upon the palette, but by intermingling them, in the manner of nature, on the canvas, so as to produce the appearance at a proper distance of a uniform colour. Thus composed is the citrine colour of fruit and foliage, on inspecting which we distinctly trace the stipplings of orange and green, or of yellow, red, and green. The truth and beauty resulting from such stipplings in art may be seen in the luscious fruit-pieces of the late W. Hunt, where the bloom on the plum, the down of the peach, &c., are given with wondrous fidelity to nature. In the russet hues of autumn foliage, where purple and orange have broken or superseded the summer green, this interlacing of colour appears; and also in the olive foliage of the rose-tree, formed in the individual leaf by the ramification of purple in green. Besides the durable yellows, reds, and blues, the following orange and green pigments are eligible for mixed citrines. They may likewise, however, be safely and simply compounded by slight additions, to an original brown, of that primary or secondary tone which is requisite to give it the required hue.

PERMANENT ORANGE. PERMANENT GREEN. Burnt Roman Ochre. Oxide of Chromium, opaque. Burnt Sienna. Oxide of Chromium, transparent. Cadmium Orange. Veronese Green. Mars Orange. Viridian. Neutral Orange. Emerald Green. Scheele's Green. Terre Verte.

226. RAW UMBER,

or Umber, is a natural ochre, chiefly composed of oxide of manganese, oxide of iron, silica, and alumina. It is said to have been first brought from ancient Ombria, now Spoleto, in Italy. Found in England, and in most parts of the world, that which comes from Cyprus, under the name of Turkish or Levant umber, is the best. Of a quiet brown-citrine colour, semi-opaque, it dries rapidly, and injures no other good pigment with which it may be mixed. By time it grows darker, a disadvantage which may be obviated by compounding it with colours which pale on exposure. For light shadow tones and delicate grays it is extremely useful, and yields with blue most serviceable neutral greens. To mud walls, tints for stone, wood, gray rocks, baskets, yellow sails, and stormy seas, this citrine is suited. Some artists have painted on grounds primed with umber, but it has penetrated through the lighter parts of the work. Mrime states that there are several of Poussin's pictures so painted; that fine series, "The Seven Sacraments," being clearly among the number.

* * * * *

227. Cassia Fistula

is a native vegetal pigment, though it is more commonly employed as a medicinal drug. It is brought from the East and West Indies in a sort of cane, in which it is naturally produced. As a pigment it is deep, transparent, of an imperfect citrine colour, inclining to dark green, and diffusible in water without grinding, like gamboge and sap green. Once sparingly used in water as a sort of substitute for bistre, it is not now to be met with on the palette.

228. Citrine Brown.

From boiling, hot, or cold solutions of bichromate of potash and hyposulphite of soda in excess, we have obtained an agreeable citrine-brown colour, varying in hue and tint according to the mode of preparation and proportions of materials employed. It is a hydrated oxide of chromium which, when washed and carefully dried, yields a soft floury powder. Transparent, and affording clear, delicate pale washes, the oxide has not been introduced as a pigment; partly owing to certain physical objections, and partly to a tendency to greenness. This tendency is peculiar to all the brown chrome oxides of whatever hue, whether hydrated or anhydrous; and indeed distinguishes more or less nearly all the compounds of chromium. Green, in fact, is the natural colour of such compounds, the colour which they are constantly struggling to attain; and hence it is that the green oxides of chromium, being clothed in their native hue, are of such strict stability. The inclination to green which the citrine under notice possesses, may be seen by washing the precipitate with boiling water. It has been supposed that hydrated brown oxide of chromium is not a distinct compound of chromium and oxygen, but a feeble union of the green oxide with chromic acid. If this be the case, the citrine cast of the brown oxide is easily explained, as well as the gradual addition to its green by the deoxidation of the chromic acid.

In mixed tints for autumn foliage and the like, the tendency to green of this citrine brown would be comparatively unimportant; but whether the oxide be adapted to the palette or not, we believe the colour might be utilized. In dyeing, for instance, the solutions of bichromate of potash and hyposulphite of soda would be worth a trial, the liquids of course being kept separate, and the brown washed with cold water. Various patterns could be printed with the bichromate on a ground previously treated with hyposulphite.

* * * * *

Several other browns, and ochrous earths, partake of a citrine hue, such as Cassel Earth, Bistre, &c. But in the confusion of names, infinity of tones and tints, and variations of individual pigments, it is impossible to arrive at an unexceptionable or universally satisfactory arrangement. We have therefore followed a middle and general course in distributing pigments under their proper heads.

Of the three citrines in common use, Mars brown and raw umber are strictly stable; while brown pink, the purest original citrine the palette possesses, is either semi-stable or fugitive, according to the colouring substance used in its preparation.



CHAPTER XV.

ON THE TERTIARY, RUSSET.

Russet, the second or middle tertiary colour, is, like citrine, constituted ultimately of the three primaries, red, yellow, and blue; but with this difference—instead of yellow as in citrine, the archeus or predominating colour in russet is red, to which yellow and blue are subordinates. For orange and purple being the immediate constituents of russet, and red being a component part of each of those colours, it follows that red enters doubly into russet, while yellow and blue appear but once therein. The proportions of its middle hue are eight blue, ten red, and three yellow, of equal intensities. Thus composed, russet takes the relations and powers of a subdued red; and many pigments and dyes of the latter denomination are strictly of the class of russet colours. In fact, nominal distinction of colours is only relative; the gradation from hue to hue, as from tint to tint, and shade to shade, being of such unlimited extent, that it is impossible to pronounce absolutely where one hue, tint, or shade ends, and another begins.

The harmonizing, neutralizing, or contrasting colour of russet, is a deep green; or when the russet inclines to orange, a gray or subdued blue. These are often beautifully opposed in nature, being medial accordances or in equal relation to light, shade and other colours, and among the most agreeable to sense.

Russet, as we have said, partakes of the relations of red, but it is a hue moderated in every respect, and qualified for greater breadth of display in the colouring of nature and art; less so, perhaps, than its fellow-tertiaries in proportion as it is individually more beautiful. The powers of beauty are ever most effective when least obtrusive; and its presence in colour should be chiefly evident to the eye that seeks it—not so much courting as being courted.

Of the tertiary colours, russet is the most important to the artist; and there are many pigments classed as red, purple, &c., which are of russet hues. But there are few true russets, and only one original pigment of that colour is now known on the palette, to wit—

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 classed 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 washing—sometimes as much as five per cent.

* * * * *

There are several other pigments which enter imperfectly into, or verge upon, the class of russet, which, having obtained the names of other classes 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 constituent: 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 finishing 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 quantity 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 passing 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 space 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 masses 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 canvass, 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 principal 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 constituents 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 pronounce 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 analogous to cobalt green may be made, of an olive hue, with more body, and equally stable.

238. Olive Scheele's Green.

Cupric arsenite, when heated, gives off arsenious acid and water, leaving a residue of arsenide of copper and copper arseniate. A series of olive colours is so afforded, which are as durable as their original pigment, and might with advantage be substituted for the doubtful compounds at present in use.

239. Olive Schweinfurt Green

is likewise furnished by gentle calcination. It may be directly prepared by mixing boiling aqueous solutions of equal parts of crystallised verdigris and arsenious acid. An olive-green precipitate is immediately formed, which is apt, without due precaution, to pass into an emerald green. A durable copper colour.

240. Olive Terre Verte.

We have obtained a very beautiful olive from terre verte by simply changing its hue. In oil, especially, the colour so produced would be found of service for autumn foliage, or richly painted foregrounds. A simple original pigment, consisting wholly of the earth, it resembles ordinary terre verte in being unaffected by strong light or impure air, and uninjured by admixture; but differs from it in not darkening by time. Semi-transparent, of sober richness and drying well in oil, it is, according to its powers, a perfectly unexceptionable colour, of strict stability.

* * * * *

Of the two olive colours in common use, olive lake and olive green, the first is generally semi-stable, and apt to blacken; while the second is usually fugitive, and liable to fade: both are compounds. The palette, therefore, possesses no original olive pigment, good or bad. A glance at the numbered italicised olives will show that the doubtful mixtures referred to might with advantage be superseded. It is clear that the olive pigments which the palette does not know, are better than those with which it is acquainted.



CHAPTER XVII.

ON THE SEMI-NEUTRAL, BROWN.

As colour, according to the regular scale descending from white, ceases properly with the last of the tertiaries, olive, in theory the neutral black would here form a fitting conclusion. Practically, however, every coloured pigment, of every class or tribe, combines with black as it exists in pigments—not simply being deepened or lowered in tone thereby, but likewise defiled in colour, or changed in class. Hence there arises a new series or scale of coloured compounds, having black for their basis, which, though they differ not theoretically from the preceding order inverted, are yet in practice imperfect or impure. These broken compounds of black, or coloured blacks and greys, we have distinguished by the term, semi-neutral, and divided them into three classes: Brown, Marrone, and Gray. What tints are with respect to white, they are with regard to black, being, so to speak, black tints or shades.

The first of the series is BROWN, a term which, in its widest acceptation, has been used to include vulgarly every kind of dark broken colour, and is, in a more limited sense, the rather indefinite name of a very extensive class of colours of warm or tawny hues. Accordingly there are browns of every denomination except blue; to wit, yellow-brown, red-brown, orange-brown, purple-brown, citrine-brown, russet-brown, &c. But there is no such thing as a blue-brown, nor, strictly, any other coloured brown in which blue predominates; such predominance of a cold colour at once carrying the compound into the class of gray, ashen, or slate. Brown comprises the hues called dun, hazel, auburn, feuillemort, mort d'ore, &c.; several of which have been already mentioned as allied to the tertiary colours.

The term brown, then, denotes rightly a warm broken colour, of which yellow is a chief constituent: hence brown is in some measure to shade what yellow is to light. Hence, also, proper quantities of either the three primaries, the three secondaries, or the three tertiaries, produce variously a brown mixture. Browns contribute to coolness and clearness by contrast when opposed to pure colours, and Rubens more especially appears to have employed them upon this principle; although the same may be said of Titian, Correggio, Paulo Veronese, and all the best colourists. Being a sort of intermedia between positive colours and neutrality, browns equally contrast colour and shade. This accounts for their vast importance in painting, and the necessity of preserving them distinct from other colours, to which they give foulness in mixture; and to this is due their use in backgrounds and in relieving of coloured objects.

The tendency in the compounds of colours to run into brownness and warmth is one of the common natural properties of colours which occasions them to deteriorate or defile each other in mixture. Brown by consequence is synonymous with foul or dirty, as opposed to fair or clean; and hence brown, which is the nearest of the semi-neutrals in relation to light, is to be avoided in mixture with light colours. Yet is it an example of the wisdom of nature's Author that brown is rendered, like green, a prevailing hue, and in particular an earth colour, as a contrast which is harmonized by the blueness and coldness of the sky.

This tendency will likewise explain the use of brown in harmonizing and toning, as well as the great number of natural and artificial pigments and colours so called. It was the fertility and abundance of browns that caused our great landscape-colourist Wilson, when a friend went exultingly to tell him that he had discovered a new brown, to check him in his characteristic way, with—"I'm sorry for it: we have gotten too many of them already." Nevertheless, fine transparent browns are obviously very valuable.

If red or blue in excess be added to brown, it falls into the other semi-neutral classes, marrone or gray. The wide acceptation of the term brown has occasioned much confusion in the naming of colours, since broken colours in which red, &c. predominate, have been improperly called brown. That term, therefore, should be confined to the semi-neutral colours, compounded of, or like in hue to, either the primary yellow, the secondary orange, or the tertiary citrine, with a black. The general contrast or harmonizing colour of such compounds will consequently be more or less purple or blue.

The number of browns is great, as may be seen by the following list. This list, however, is good, and includes a considerable proportion of permanent pigments.

241. ASPHALTUM,

Asphalt, Bitumen, Mineral Pitch, Jew's Pitch, Antwerp Brown, Liquid Asphaltum, &c., is a sort of mineral pitch or tar which, rising liquid to the surface of the Lacus Asphaltites or Asphaltic Lake (the Dead Sea) concretes there by the natural action of the atmosphere and sun, and, floating in masses to the shores, is gathered by the Arabs. The French give it an additional name from the region of the lake, to wit, Bitumen of Judea; and with the English, from the same cause, it has the alias of Jew's pitch. Asphaltum is not so called, however, after the lake, as is asserted by a writer in the Encyclopdia: it is just the reverse—Pliny says, "The Asphaltic lake produces nothing but bitumen (in Greek, asphaltos); and hence its name."

A substance resembling asphalt is found at Neufchtel in Switzerland, and in other parts of Europe. A specimen of the native bitumen, brought from Persia, and of which the author made trial, had a powerful scent of garlic when rubbed. In the fire it softened without flowing, and burnt with a lambent flame; did not dissolve by heat in turpentine, but ground easily as a pigment in pale drying oil, affording a fine deep transparent brown colour, resembling that of commercial asphaltum; dried firmly almost as soon as the drying-oil alone, and worked admirably both in water and oil. Asphaltum may be used as a permanent brown in water, for which purpose the native is superior to the artificial. The former, however, is now seldom to be met with, the varieties employed on the palette being the residua of various resinous and bituminous matters, distilled for the sake of their essential oils. These residua are all black and glossy like common pitch, which differs from them only in having been less acted upon by fire, and thence in being softer. At present asphaltum is prepared in excessive abundance as a product of the distillation of coal at the gas manufactories, and is chiefly confined to oil-painting, being first dissolved in turpentine, which fits it for glazing and shading. Its fine brown colour and perfect transparency are lures to its free use with many artists, notwithstanding the certain destruction that awaits the work on which it is much employed, owing to its tendency to contract and crack by changes of temperature and the atmosphere; but for which, and a slight liability to blacken, it would be a most beautiful, durable, and eligible pigment. The solution of asphaltum in turpentine, united with drying oil by heat, or the bitumen torrefied and ground in linseed or drying-oil, acquires a firmer texture, but becomes less transparent and dries with difficulty. If common asphaltum, as usually prepared with turpentine, be used with some addition of Vandyke brown, umber, or Cappah brown ground in drying oil, it will gain body and solidity which will render it much less disposed to crack. Nevertheless, asphaltum is to be regarded in practice rather as a dark varnish than as a solid pigment, and all the faults of a bad varnish are to be guarded against in employing it.

It is common to call the solution in turpentine Asphaltum, and the mixture with drying-oil Bitumen: the latter is likewise known as Antwerp Brown. A preparation for the use of water-colour artists is employed under the name of Liquid Asphaltum.

242. BISTRE

is extracted by watery solution from the soot of wood fires, whence it derives a strong pyroligneous scent. It is a very powerful citrine-brown, washes well, and has a clearness suited to architectural subjects. Its use is confined to water-colour painting, in which it was much employed by the old masters for tinting drawings and shading sketches, before the general application of Indian ink to such purposes. Of a wax-like texture, it is perfectly durable, but unfitted for oil, drying therein with the greatest difficulty.

A substance of this kind collects at the back of fire-places in cottages where peat is the constant fuel burnt; which, purified by solution and evaporation, yields a fine bistre, similar to the Scotch. All kinds of bistre attract moisture from the atmosphere.

243. BONE BROWN

and Ivory Brown are obtained by roasting bone and ivory until by partial charring they become of a brown colour throughout. Though much esteemed by some artists, they are not quite eligible pigments, being bad driers in oil, the only vehicle in which they are now used. Moreover, their lighter shades are not permanent either in water or oil when exposed to the action of strong light, or mixed in tint with white lead. The palest of these colours are the most opaque: the deepest are more durable, and most so when approaching black. Neither bone nor ivory brown is often employed, but the former may be occasionally applied in forming clear, silvery, warm grays, in combination with zinc white.

244. BURNT UMBER

is what its name denotes, and has a deeper shade with a more russet hue than the raw umber. A quiet brown, it affords clear and warm shadows, but is apt to look rather turbid if used in great depth. It washes and works capitally in water, and dries quickly in oil, in which it is employed as a siccative. Perfectly stable in either vehicle, it may sometimes be substituted for Vandyke brown, is eligible in fresco, and invaluable in buildings. Where the lakes of madder require saddening, the addition of burnt umber increases their powers, and improves their drying in oil. It contains manganese and iron, and may be produced artificially. The old Italians called it falsalo.

245. CALEDONIAN BROWN

is a permanent native pigment, the use of which is confined to oil. A magnificent orange-russet brown of considerable transparency, it is marked by great depth and richness, and will be found serviceable where a powerful brown of the burnt Sienna class is required.

246. CAPPAH BROWN,

or Cappagh Brown, is likewise a colour peculiar to oil. It is a species of bog-earth or peat, mixed with manganese in various proportions, and found on the estate of Lord Audley at Cappagh, near Cork. The specimens in which the peat earth most abounds are of light weight, friable texture, and dark colour; while those which contain more of the metal are heavy and paler.

As pigments, the peaty Cappah brown is the most transparent and rich in colour. A prompt drier in oil, its surface rivels during drying where it lies thick. The other and metallic sort is a more opaque, a lighter and warmer brown pigment, which dries rapidly and smoothly in a body or thick layer. The first may be regarded as a superior Vandyke brown, the second as a superior umber. The two extreme kinds should be distinguished as light and deep Cappah browns; the former excellent for dead colouring and grounds, the latter for glazing and graining. These pigments work well in oil and varnish; they do not, however, keep their place while drying in oil by fixing the oil, like the driers of lead, but run. Under the names of Euchrome and Mineral Brown, they have been introduced into commerce for civil and marine painting.

247. CASSEL EARTH,

Terre de Cassel, or, corruptly, Castle Earth, is specially an oil pigment, similar to burnt umber but of a more russet hue. It is an earth containing bitumen, a substance which, with pit-coal, lignite or brown coal, jet, petroleum or rock oil, naphtha, &c., is looked upon as a product of the decomposition of organic matter, beneath the surface of the earth, in situations where the conditions of contact with water, and almost total exclusion of atmospheric air, are fulfilled. Deposited at the bottom of seas, lakes, or rivers, and subsequently covered up by accumulations of clay and sand, the organic tissue undergoes a kind of fermentation by which the bodies in question are slowly produced. The true bitumens appear to have arisen from coal or lignite by the action of subterranean heat; and very closely resemble some of the products yielded by the destructive distillation of those bodies.

Rich as is the tone of colour of Cassel earth, it is apt to lose this in some measure on exposure to light. Mrime remembers to have seen a head, the brown hair of which had been painted partly with the earth alone, and partly with a mixture of the earth and white; yet the hair where the white was employed was darker than that painted solely with the brown, the white having fixed the colour. To compensate for its thus fading, it should be mixed with pigments that are permanent, such as umber and lamp black. Like all bituminous earths, it needs the strongest drying oil. By calcination, a greater degree of intensity may be imparted to the colour, and perhaps a little more solidity. In landscapes it is of much service for the most vigorous portions of foregrounds and the trunks of trees, as well as for painting cavernous rocks or deep recesses in architecture. Compounded with burnt lake and a little Prussian blue, it gives a black the most profound.

248. CHALON'S BROWN

is a water-colour pigment, transparent and inclining to red; deep, full, and very rich. On exposure to light it becomes less russet, but is otherwise strictly stable.

249. COLOGNE EARTH,

incorrectly called Cullen's Earth, is a native bituminous earth, containing less bitumen than Cassel earth, and therefore drying more quickly. Darker than that variety, it is less transparent, and covers better. In its general qualities it resembles Vandyke brown, except that in combination with white, it affords a range of cooler brown tints. Useful for the shadows of buildings, it does not wash so well as sepia, and is preferred occasionally on that account. By some it has been called durable, by others branded as fugacious. According to Bouvier, brown hair represented by this colour has been known to disappear in six months, all the brown vanishing, and nothing remaining but a few black lines of the sketch. As it is similar in composition to Cassel earth, the safest course would be to mix it with umber, and not to employ it alone. Calcined, it acquires a reddish hue.

250. INDELIBLE BROWN INK.

Although this cannot be classed as a pigment, yet, being very useful in water-colours, it may be proper to describe its qualities. The ink is a rich brown fluid, and, as its name imports, is indelibly fixed on the paper as soon as it is dry; thus allowing the artist to work or wash over it repeatedly, without its being disturbed. If diluted with water to its faintest tint, it still continues to retain its indelible properties undiminished. It is generally used with a reed pen, and employed chiefly in architectural details and outlines.

Various brown inks, principally solutions of bistre and sepia, were adopted in sketching by Claude, Rembrandt, and many of the old masters. In modern times, a beautiful transparent brown for water-colour artists, known as Liquid Prout's Brown, has been extensively employed. This contains less fixative than the indelible ink, and is the vehicle with which nearly all Samuel Prout's drawings were executed.

251. LEITCH'S BROWN

is a permanent pigment peculiar to water painting. A most beautiful olive brown, soft and rich, it is admirably adapted for autumnal foliage tints and the like, either alone or compounded with burnt Sienna or cadmium orange. Transparent and clear in its washes, this is a most serviceable colour in landscape generally.

252. MIXED BROWN

can be produced in endless variety, either by adding a warm colour to black, such as yellow, orange, or citrine, or else by combining the three primaries, secondaries, or tertiaries in suitable proportions. By consulting the lists given of permanent pigments belonging to those classes, and by referring to the chapter on Black, it will be seen that no difficulty exists in obtaining durable mixed browns when required. For example, there may be formed from the primaries, a compound of aureolin, rose madder, and ultramarine; or from the secondaries, a mixture of cadmium orange, viridian, and madder purple. Of course, as with other mixed tints, the brown hue can be furnished not only by direct compounding of the colours on the palette, but by laying one colour over the other on the paper or canvass, or by stippling.

253. MUMMY,

Mummy Brown, or Egyptian Brown, is a bituminous product mixed with animal remains, brought from the catacombs of Egypt, where liquid bitumen was employed three thousand years ago in embalming. By a slow chemical change, it has combined during so many ages with substances which give it, as a rule, a more solid and lasting texture than simple asphaltum. Generally resembling the latter in its other properties and uses as a pigment, mummy is often substituted for it, being less liable to crack or move on the canvass. It must be remembered, however, that mummy varies exceedingly both in its composition and qualities; and as from its very nature and origin nothing certain can be said of it, but little reliance should be placed on this brown. Mummy belongs to the class of pigments which are either good or bad, according as they turn out. On the whole, we agree with the American artist, who has been more than once quoted in these pages, that nothing is to be gained by smearing one's canvass with a part, perhaps, of the wife of Potiphar. With a preference for materials less frail and of a more sober character, we likewise hold with Bouvier, that it is not particularly prudent to employ without necessity these crumbled remains of dead bodies, which must contain ammonia and particles of fat in a concrete state and so be more or less apt to injure the colours with which they may be united. The use of mummy is now confined to oil, in which, says Mr. Carmichael, a mixture of mummy and bitumen will dry and never crack. If this be the case, the compound would be preferable to either separate.

254. PRUSSIAN BROWN

is an iron oxide, containing more or less alumina, and prepared by calcining an aluminous Prussian blue, or treating an aluminous ferrocyanide of peroxide of iron with an alkali. Possessing the nature and properties of burnt Sienna, it is transparent, permanent, and dries well in oil. Of an orange hue, it is neither so rich nor so powerful as that pigment, and is better employed as a glaze than in body.

255. SEPIA,

Liquid Sepia, Seppia, or Animal thiops, is named after the sepia or cuttle-fish, also called the ink-fish, from its affording a dark liquid, which was used as an ink and pigment by the ancients. All the species of cuttle-fish are provided with a dark-coloured fluid, sometimes quite black, which they emit to obscure the water, when it is wanted to favour their escape from danger, or, by concealing their approach, to enable them with greater facility to seize their prey. The liquid consists of a mass of extremely minute carbonaceous particles, intermixed with an animal gelatine or glue, and is capable of being so widely spread, than an ounce of it will suffice to darken several thousand ounces of water. From this liquid, brought chiefly from the Adriatic, but likewise obtainable from our own coasts, is derived the pigment sepia, as well as, partially, the Indian ink of the Chinese.

Sepia is a powerful dusky brown, of a fine texture, transparent, works admirably in water, combines cordially with other pigments, and is very permanent. It is much used as a water-colour, and for making drawings in the manner of bistre and Indian ink; but is not employed in oil, as it dries therein very reluctantly. Extremely clear in its pale tints, and perhaps the best washing colour known, sepia must be used with caution, or otherwise heaviness will be engendered in the shades, so strong is its colouring property. Mixed with indigo, or, preferably, Prussian blue and black, it is eligible for distant trees, for a general shadow tint in light backgrounds, and for the shade of white linen or white draperies. With madder red it forms a fine hue, somewhat resembling brown madder, and with crimson lake and indigo gives an artistically excellent black. Sometimes alone and sometimes in combination with lamp black, or madder red and Prussian blue saddened by the black, it will be found useful in dark foreground boats, rocks, near buoys, sea-weed, &c. Compounded with aureolin, sepia yields a series of beautiful and durable neutral greens for landscape; and mixed with Prussian blue, affords low olive greens, which may be deepened into very cool dark greens by the addition of black. For hills and mountains in mid-distance, sepia combined with cobalt and brown madder is of service; or, for the dark markings and divisions of stones in brooks and running streams, the same compound without the cobalt. Mixed with purple madder, it furnishes a fine tint for the stems and branches of trees; and with French blue and madder red gives a really good black. Compounds of sepia and yellow ochre, gamboge, raw Sienna, or cobalt and aureolin, are severally useful. A rich and strong brown is formed by the admixture of madder red, burnt Sienna, and sepia; a tint which may be modified by omitting the sepia or the Sienna, or reducing the proportions of either. For Dutch craft, this tint and its variations are of great value. A wash of sepia over green very agreeably subdues the force of the colour.