u are painting; but if you wish it to be smooth, just
give a last stroke or two over the whole glass sideways, that is to say,
holding the badger so that it stands quite perpendicular to the glass,
move it, _always still perpendicular_, across the whole surface. You
must not sway it from side to side, or kick it up at the end of each
stroke like a man white-washing; it must move along so that the points
of the hairs are all just lightly touching the glass all the time.

[Illustration: FIG. 30.]

_How to Ensure the Drawing of a Face being kept Correct while
Painting._--If you adopt the plan of doing the first painting over an
unfired outline, you must be very careful that the outline is not
brushed out of drawing in the process. If you have sufficient skill it
need not be so, for it is quite possible--if all the conditions as to
adhesiveness are right--and if you are light-handed enough--to so lay
and badger the "matt" that the outline beneath shall only be gently
softened, and not blurred or moved from its place. But in any case the
best plan is at the same time that you trace the outline of a head on to
the glass to trace it also with equal care on to a piece of tracing
paper, and arrange three or four well-marked points, such as the corner
of the mouth, the pupil of the eye, and some point on the back of the
head or neck, so that these cannot possibly shift, and that you may be
able at any time to get the tracing back into its proper place, both on
the cartoon and on the piece of glass on which you are to paint the
head. On which piece of glass also your first care should be that these
three or four points should be clearly marked and unmovable; then during
the whole progress of the painting you will always be able to verify the
correctness of the drawing by placing your piece of tracing paper over
the glass, and so seeing that nothing has shifted its place.

[Illustration: FIG. 31.]

It requires a good deal of patience and practice to lay matt
successfully over unfired outline. It is a question of the amount and
quality of the gum, the condition of your brush, even the dryness or
dampness of the air. You must try what degree of gum suits you best,
both in the outline and in the matt which you are to pass over it. Try
it a good many times on a slab of plain glass or on the plate of your
easel first, before you try on your painting. Of course it's a much
easier thing to matt successfully over a small piece than over