Most Viewed

- Browns And The Cold Semi-neutral Grays Marrone Is Practically To
- Also Called Scarlet Chrome Is A Bright Chromate Of Lead Of An
- Black Chalk
- Composition Chemical Analysis Has Shown Several Of The Blues To Be
- Burnt Verdigris
- Belong The Dutch And Flemish Schools; The Sensible Which Aims At
- Less Known As English Red Prussian Red And Scarlet Ochre True
- Olive In Dark Green; Russet And Citrine In Dark Orange The
- Known Likewise As Raw Sienna Earth Terra Di Sienna &c Is A
- Root Of The Anchusa Tinctoria Commonly Known As Alkanet A Plant

Least Viewed

- Distilled Verdigris Or More Properly Refined Verdigris The Best Is
- Sometimes Called China Or Chinese Ink Is Chiefly Brought From
- Their Chief Source The Greens Consist Of Yellow Mixed With Copper
- Egypt The Greeks Obtained The Knowledge Of Their Ars Chromatica
- While We Avoid The Compounding Of Contrasting Colours That Is The
- Only That Of Extreme Light Objects Opaque It Follows That White Is To
- Secondary Colours Are Three Only Orange Green And Purple
- Colours With The Neutral Black Of The Various Combinations Of Black
- Have To Be Learnt For Each Pigment Has Its Own Peculiar Habitudes
- These Are False Appellations Of A White Lead Called Also French

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

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,





Next: A Mixture Will Slowly But Surely Lose The Colour For Which It Was
Previous: Orange Chrome Or Orange Chromate Of Lead Is A Sub-chromate Of Lead

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