And Ivory Brown Are Obtained By Roasting Bone And Ivory Until By
:
ON THE SEMI-NEUTRAL, BROWN.
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
mo
e 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.
TTITLE 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