: ON THE NEUTRAL, BLACK.
is a native impure carbon of soft texture, found in Devonshire. Blacker
than plumbago, and free from its metallic lustre, it is of a neutral
colour, greyer and more opaque than ivory black, and forms pure neutral
tints. Being perfectly durable, and drying well in oil, it is of value
in dead colouring on account of its solid body, as a preparation for
black and deep colours before glazing. It would likewise be the most
permanent and best possible black for frescoes.