Orange De Mars Is A Subdued Orange Of The Burnt Sienna Class But

: ON THE SECONDARY, ORANGE.

without the brown tinge that distinguishes the latter. Marked by a

special clearness and purity of tone, with much transparency, it affords

bright sunny tints in its pale washes, and combines effectively with

white. Being an artificial iron ochre it is more chemically active than

native ochres, and needs to be cautiously employed with pigments

affected by iron, such as the lakes of cochineal and intense blue.


/> TTITLE MIXED ORANGE.



Orange being a compound colour, the place of original orange pigments

can be supplied by mixtures of yellow and red; either by glazing one

over the other, by stippling, or by other modes of breaking and

intermixing them, according to the nature of the work and the effect

required. For reasons lately given, mixed pigments are apt to be

inferior to the simple or homogeneous both in colour, working, and other

properties; yet some pigments mix and combine more cordially and with

better results than others; as is the case with liquid rubiate and

gamboge. Generally speaking, the compounding of colours is easier in oil

than in water; but in both vehicles trouble will be saved by beginning

with the predominating colour, and adding the other or others to it.



Perhaps in this, our first chapter on the secondary colours, and

consequently on colours that can be compounded, a few remarks on mixed

tints from a chemical point of view will not be deemed superfluous.



There are two ways, we take it, of looking at a picture--from a purely

chemical, and from a purely artistic, point of view. Regarded in the

first light, it matters little whether a painting be a work of genius or

a daub, provided the pigments employed on it are good and properly

compounded. The effects produced are lost sight of in a consideration of

the materials, their permanence, fugacity, and conduct towards each

other. Painting is essentially a chemical operation: with his pigments

for reagents, the artist unwittingly performs reaction after reaction,

not with the immediate results indeed of the chemist in his laboratory,

but often as surely. As colour is added to colour, and mixture to

mixture, acid meets alkali, metal animal, mineral vegetable, inorganic

organic. With so close a union of opposite and opposing elements, the

wonder is not so much that pictures sometimes perish, but that they ever

live. It behoves the artist, then, not only to procure the best and most

permanent pigments possible, but to compound them in such a manner that

his mixed tints may be durable as well as beautiful. To effect or aid in

effecting this, although he may not always be able to act upon them, the

following axioms should be borne in mind:--



1. If they do not react on each other, a permanent pigment added to a

permanent pigment yields a permanent mixture.



2. If they do react on each other, a permanent pigment added to a

permanent pigment yields a semi-stable or fugitive mixture.



3. A permanent pigment added to a semi-stable pigment yields a

semi-stable mixture.



4. A permanent pigment added to a fugitive pigment yields a fugitive

mixture.



Consequently--



5. A permanent pigment may be rendered fugitive or semi-stable by

improper compounding.



6. A semi-stable or fugitive pigment is not rendered durable by being

compounded.



7. As a chain is only as strong as its weakest link, so a mixture is

only as permanent as its least durable constituent.



To give illustrations--



1. Ultramarine added to Chinese white yields a permanent mixture.



2. Ultramarine added to an acid constant white yields a semi-stable or

fugitive mixture.



3. Ultramarine added to Prussian blue yields a semi-stable mixture.



4. Ultramarine added to indigo yields a fugitive mixture.



Except in the second instance, where the blue is either partially or

wholly destroyed--in time, be it remembered, not at once--according to

the quantity and strength of the acid in the white, the ultramarine

remains unchanged. Hence at first sight our third and fourth conclusions

may appear wrong; inasmuch as, it may be argued, a blue mixture cannot

be semi-stable or fugitive when blue is left. To this we reply, unless

both constituents are fugitive, a mixture will always more or less

possess colour; but, if even one constituent be semi-stable or fugitive,



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