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- 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

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- Distilled Verdigris Or More Properly Refined Verdigris The Best Is
- Uniform Colour Thus Composed Is The Citrine Colour Of Fruit And
- 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

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 Encyclopaedia: 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 Neufchatel 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.





Next: It Is Common To Call The Solution In Turpentine Asphaltum And The
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