An 1847 manual of oil painting explains: “When the lights of a
painting are so arranged that they seem to be in masses, and the
darks are massed to support them, we have what is called breadth
of effect, which is mainly produced by the coloring and
chiaroscuro." The painting "Blessing of the Young Couple Before
Marriage" by Pascal Dagnan Bouveret is a good example of
breadth. The white of the bride's dress joins with the table
cloth, the shaft of light, and the other women's dresses to make
a single large shape. Meanwhile, two groupings of dark-clad
figures join to form larger masses. The painting manual says
that the quality of breadth applies to both design and coloring,
and that it is indicative of a master. Indeed it's difficult to
achieve, because one must overcome the natural inclination to
separate and define shapes throughout the composition.