thin wash of transparent color flowed over an
under-painting to modify its tone or to add to its effect. It is not
always transparent color, but usually it is. Sometimes opaque or
semi-opaque color may be used, and it is a glaze by virtue of the fact
that it is thinned with a vehicle either oil or varnish, and _flowed_
on. A scumble is _rubbed_ on, and is never pure transparent color.

=Advantages of Glazing.=--The advantages are the gain in harmony, in
force, in brilliancy; you may correct a color when it is wrong, or
perfect it when it is not possible to get the force or richness
required without it. These are the qualities which have made it used
by all schools more or less.

=Disadvantages.=--There are, however, quite as evident and marked
disadvantages. The free use of oil as a thinning vehicle, although it
makes possible a greater degree of richness of color, is very likely
to turn the picture brown in time. Oil will always eventually have a
browning effect on all paints, even when mixed with them as little as
is absolutely necessary. If you make a tinted varnish of oil (which
is practically what a glaze is), you add so much, to the surely
darkening action of the oil on the picture.

If, again, you depend upon a glaze for the richness of color for your
picture, and you use a color which is not permanent, your glaze fades,
and your color is not there. A glaze is particularly liable to be
injured by the cleaner if it ever gets into his hands. He works down
to fresh color, and what with the browning of the glaze and the fact
that the cleaner is more anxious that the picture should be cleaned
than that its color should be fine, he will, in nine cases out of ten,
_clean_ off the glaze which may be the final and most expensive color
the painter has put on it.

Glazing is little used nowadays, compared with what it once was. But
there are times when you cannot get what you want in any other way,
and when you are sure that glazing is the only thing which will give
you your result, the only law for the painter comes in,--get your
result.

=Precautions.=--If you do glaze, however, there is a right and a wrong
way. You should not use a glaze as a last resort. It is better to
calculate on it beforehand; for you always glaze with a darker tint
upon a lighter one, so that if you have not allowed for this, you will
get your picture too low in tone before you know it.

If you want to make your picture, or a part of it, bri