Howard, Frank: Colour, as a means of art: being an adaptation of the experience of professors to the practice of amateurs (London, 1838)

26 HARMONY.

with each other, that they still form parts of a
whole :—that whether the lights be white, and the
shadows black, or differently coloured, the same
necessity for graduation remains, so that Colours
must not be in flat patches. And in the treatment of
Colours, besides the graduation requisite for Breadth
of Chiaroscuro, it is necessary to pay attention to
the peculiar quality termed Tone, which is indis-
pensable in a coloured Work of Art.

As well as Breadth of Chiaroscuro, there must
be Breadth of Tone, the fundamental quality of
Harmony.