Incorrectly Called Cullen's Earth Is A Native Bituminous Earth
: ON THE SEMI-NEUTRAL, BROWN.
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
led 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.
TTITLE 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,