METHOD OF PAINTING FAIENCE UNDER THE GLAZE WITH THE USE OF BODY COLOR.
The method of decorating pottery here described is similar in its
effects to what is known as the Haviland, or Limoges faience, and is
given as the result of numerous experiments made by the writer.
The finished work presents the appearance of a painting in oil, to
which a brilliant glaze has been applied. This glaze not only renders
the colors unchangeable, but gives a beauty and effectiveness which
could be acquired in no other way. There is nothing peculiar in
regard to this glaze, however, the only requisite being that it
should be suited to the body of the ware, and that the latter and its
glaze must not require so great a degree of heat in firing that the
colors shall be injured. This matter of the glaze has been almost
uniformly misrepresented in accounts of the ware which have been
published. It has been said that the peculiar effect of the work was
due to the glaze, and that the secret of making it was not generally
known. This is not at all true, as the results are due solely to the
peculiar method of painting, and the glaze is simply the process
by which it is finished, and bears the same relation to it as the
varnish does to the painting in oil. The work will suffer, of course,
if this part of it is not well performed; but the distinguishing
feature of the method consists not in the glaze, but in the use of
clay, which is mixed with coloring oxides, capable of bearing a high
degree of heat in firing, and which gives them body, producing a
thick _impasto_ in the painting. The work partakes, therefore, both
of the nature of painting and modeling, as the high lights may be
laid in so thickly as to produce an actual relief.
It is somewhat difficult, indeed, almost impossible, to give a
correct idea of the palettes to be used in this kind of painting.
If colors could be procured, already prepared for use, as oil
paints are, and these colors had the same appearance after firing
as before, it would be comparatively an easy task. As it is, the
colors must be mixed with clays in certain proportions, and, on
account of the change produced by firing, the proportions necessary
to produce the intensity of color desired, can only be determined
from experience. The result, after the work is finished, differs from
its appearance before firing to a greater extent than in any other
kind of decoration upon pottery. As a rule, it may be said that the
colors are intensified by firing. This is also true of other kinds
of under-glaze painting, but not in so great a degree as in the case
in question. The harmonies and contrasts of color can be kept only
in the mind of the artist, and every part of the work must be done
with a view to the result when finished, which, as has been said,
will differ materially from its appearance during the progress of
the painting. Experience only, can give an accurate idea of these
changes. This, however, is not an insurmountable difficulty; care and
patience added to the requisite artistic ability, will soon lead to
satisfactory results.
Before describing the method of painting, it may be well to consider
the kind of clay of which the body of the ware should be made, and
the state in which the painting should be applied. As to the clay
forming the body of the ware, it must be of such a nature as to
adapt itself to a glaze sufficiently soft to preserve the colors. As
the clay used in the painting must, of necessity, in most cases, be
white, in order that the purity and beauty of the colors may not be
affected by admixture with it, a body of the same, or very nearly
resembling it, would, in some respects, be the best, one reason for
this being that the applied clay would be more certain to adhere
firmly to the body, both having the same qualities. The proper glaze
for such a body would, however, require too great a degree of heat
in the firing, and none but the strongest colors could bear it
without injury.
In order, therefore, that the glaze may be perfectly adapted to the
body of the ware, and yet require no greater degree of heat than
the colors used in the painting will bear, it is best to use a body
formed from materials which do not need to be fired at a very high
temperature. This desired quality is found in some of the natural
colored clays. A mixture partaking of the qualities of both yellow
and red clay, without the unpleasant color of the former, and
possessing greater strength than the latter, has been found to be the
best.
THE STATE OF THE WARE IN WHICH THE PAINTING SHOULD BE APPLIED.
For this method of decoration the ware should be in the “green”
state. The more moisture it contains the better, and it will be in
proper condition if procured as soon as it leaves the hands of the
molder, or as soon as it has become sufficiently dry to retain its
shape. Pieces can be kept in this state a considerable length of
time, by placing them in a box which has been lined with plaster of
paris. This lining should be about an inch thick, and if the inside
is occasionally sprinkled with water, it will remain moist, and keep
the clay in good condition. A box of this kind is really invaluable
for all work, where it is necessary to keep clay moist. Within
certain limits the clay is improved rather than injured by keeping
in this way; the effect upon it being that it becomes tougher and
more plastic. If kept too long, it becomes “rotten,” and the plastic
quality is lost, but it will keep a reasonable length of time, even
two or three months. If the box can not be had, the pieces may be
covered by a rubber cloth, which should be kept from touching them
by a frame of wood or galvanized iron wire, damp cloths having been
placed around them to produce sufficient moisture.
It is necessary to exercise this care in keeping the ware moist,
in order to prevent the clay, which is applied to the surface in
painting, from cracking during the process of drying. It must always
be borne in mind that the material made use of in painting is simply
clay, which has been artificially colored, and, as clay, becomes
subject to the rules which govern all work of this kind, whether it
is making pottery, modeling, or painting faience.
To produce depth and richness of effect, the painting should have
a heavy _impasto_, and the high lights should be laid on in such a
manner as almost to present the appearance of modeling in relief.
When this is done, there is a tendency in the applied clay to crack
in drying, if the conditions are not right. In applying one piece
of clay to another, it is requisite that both should be of the same
consistency, to ensure equal contraction. In this case, however, the
clay is used as paint, and must be of such consistency as will permit
its manipulation with the brush. Its application, then, to a body
of clay that has lost much of its moisture, is attended with some
risk, and the fact that the coating of clay is comparatively thin,
alone renders it possible to defy one of the conditions which govern
the use of this material. When the piece of ware, upon which this
painting is applied, has previously become too dry, the moisture in
the coating of clay is very quickly absorbed into the body, and this
causes it to shrink unequally with the body, and thus to crack. When
the body and the applied clay are more nearly in the same condition,
and the former still retains considerable moisture, it does not
absorb that of the clay on the surface so rapidly, and they shrink
and dry together.
The drying of the clay used in painting can, however, be retarded
by the use of gum tragacanth, which may be mixed with it. It would,
perhaps, be better always to take the precaution to use this medium,
although when, as remarked before, the body of the ware is still
quite soft, and the condition of the atmosphere such as to prevent
too rapid drying, the painting may be executed simply with the use of
water.
Just here a caution as to the use of gum tragacanth may be given,
and that is, that it is better not to mix the gum with more of the
colored clay prepared for painting than is to be used at once. When
mixed only with water, the clay after becoming dry, can be easily
rubbed down again with water; but if gum tragacanth has been used in
the mixture, and it has been allowed to dry upon the palette, the
gum will not re-dissolve readily under the action of water and the
palette knife, and the mixture will be full of small particles of
undissolved gum, which will render it unpleasant to work with. To
prepare gum tragacanth for use, it is dissolved in water, to which
may be added a drop of salicylic acid to keep it from turning sour.
The clay, which is to form a body for the colors, must be dissolved
in water until of a proper consistency for painting. It should be a
little thicker than the diluted clay used by potters and technically
called “slip.” As to the quality of the clay, the desideratum is
that it shall be colorless and not inclined to crack in drying. The
clay used in the manufacture of white granite ware is probably the
best clay for this purpose, generally accessible. This can be mixed
with all the colors without injury to the tint of any. Parian clay
produces the most beautiful effects, and, where it is possible to
procure it, forms the best medium for this painting. More care must,
however, be exercised in its use, as it is very liable to crack in
drying, and from the translucency produced in the body by the action
of the fire, must be laid on more thickly than clays which have
greater opacity, to produce the effect desired.
In the case of yellow, which does not always stand the fire well,
it is best to mix the color with a yellow-tinted clay to ensure a
successful result. C. C. clay, which is a cream-tinted white, will
effect this. If a darker yellow is desired, clay which in firing
acquires a decided yellow-tint may be used.
A light cream-tinted clay, such as C. C., or “stilt” clay, may be
used with yellows therefore, with advantage, with browns and blues
without disagreeable effects; but in the case of scarlet, pink, or
crimson and greens, nothing but white clay must be used, if purity
of tint is desired. The reason for this is that the presence of iron
in the yellow-tinted clays injures the colors mentioned.
The clay can be procured from the pottery in broken pieces, or,
better, in a semi-pulverized state from the trimming in making the
wares. When in this state it is easy at any time to dissolve enough
for use. It is, perhaps, better to prepare it just before it is to be
used, as the longer clay stands, after it has been mixed with water,
the more compact it becomes. When it has just been dissolved, it
still retains air among its particles, and this renders the mixture
more porous and less liable to crack. It soon dissolves in water and
can be stirred until smooth. It may be strained through a sponge,
alternately allowing the sponge to absorb the diluted clay and then
squeezing it. Probably the most convenient way is to rub the clay in
a mortar until all the lumps are dissolved. If a very small quantity
only is needed it may be rubbed down upon the palette with the
palette knife as it is wanted.
A palette or a slab of glass may be used for mixing the colors and
clay. The latter is the best, as it can be procured of large size,
and as in this kind of work a considerable quantity of paint is
necessary, there should be ample room to mix the colors. A slab of
French plate glass, at least twenty by twenty-four inches, may be
procured. This can be imbedded in plaster of paris, which will make
it stronger, as well as furnish a white surface upon which the colors
will show to better advantage.
The powdered colors as procured are not perfectly pulverized, and
must be well rubbed down with a muller and palette knife. It is even
more necessary in this than in other kinds of painting upon pottery
that the color should be well ground. If not rubbed down sufficiently
_before being mixed with the clay_, particles of color which are
scarcely apparent before firing, will show when the work is glazed,
forming specks in what should be, a perfectly uniform tint. If the
color is mixed with the clay before it has been perfectly dissolved,
it will not afterward be possible by any rubbing down to remove the
specks from the mixture.
The colors, after being thoroughly ground, can be mixed with clay in
such proportions as may be desired. The white clay takes the place
of white, and is used to lighten every tint, as well as to form a
body for the colors. It is a good plan, where experience has rendered
it possible to do it with judgment and certainty of result, to mix
the various tints in water with clay, in quantities, and then allow
them to dry. When dry, they can be pulverized and the colored powder
can be put away in bottles for future use. This saves time when
painting, and also ensures a like result from the use of a mixture
which has already been tested and found to be satisfactory. It is
only, however, after considerable experience in mixing colors, and
verifying their results, that this can be safely done.
As in other kinds of underglaze painting, it may be given as a
general rule, that the colors are intensified in firing, in this,
however, much more than in other methods. All the stronger colors
are intensified to a degree difficult to realize before experience
has taught the artist what to expect. They all become several shades
darker, and, in the case of blues, blacks and greens, it is more
difficult to obtain delicacy, than depth of tint.
In the use of scarlet, crimson and yellow, a considerable amount
of the color in proportion to the clay must be used for the darker
portions to give sufficient depth. Only enough clay must be taken
to give body to the paint, and the mixture should then be applied
very thickly. The painter must also bear in mind the fact that the
stronger color will overpower the weaker in mixtures, even when the
latter is in such degree as to give the color to the mixture before
firing. After firing, the stronger color will appear in excess. In
making such mixtures, therefore, the stronger color should be used
very sparingly, if it is desired that the other should predominate in
the tint when fired. Otherwise, the colors may be found after firing
to be entirely different from what was intended.
METHOD OF PAINTING.
Let us suppose that the artist wishes to paint a vase. A certain
tint being selected for the ground, the color, or colors, which are
to produce it are mixed in their relative proportions, according to
the hints given above. A sufficient quantity should be prepared to
paint the whole ground, especially if a mixed tint, which it would
be difficult to reproduce in its exact proportions. It will require
some little experience to enable the artist to judge how much will
be needed, and, perhaps, it will be somewhat difficult for any one
accustomed to painting in other methods, to realize the quantity of
paint used in this. It is better to have too much mixed than too
little, as it can be kept and used another time.
The color, or colors, for the ground having been rubbed down until
perfectly smooth, as directed before, may be mixed with more or
less clay, according to the shade of color desired. The first tint
may be made to represent the darkest shade in the ground, and a
comparatively small amount of clay should be used. After the color
has been mixed with the clay, it can be placed on one side of the
palette. By taking portions from it and adding more clay, other
shades of the same color may be made. First, a light tint may be
prepared for the first coat upon the vase.
Before commencing to lay on the ground, it is well to wash the
surface of the vase with a thin solution of glaze (such as is used
for finishing the ware), or with borax water. This is to ensure the
adhesion of the clay, of which the painting is to consist, to the
clay of which the vase is made. Previous to this, the vase, if not
already in good condition, should be washed over with a brush, or
with a sponge dipped in water, or sprinkled until it has absorbed
water enough to keep the clay, which is to be applied to its surface,
from drying too quickly.
A broad, flat camel’s-hair brush may then be charged with the
_light tint_, and the surface of the vase covered with it as evenly
as possible, and so thickly as to completely obscure the body. This
done, another tint, darker than the first, in a degree sufficient to
permit their being distinguished from each other, may be mixed. This
will form the middle tint of the ground, and is to be laid on over
the first. The reason for applying two coats is, that, although it
might be possible to paint one with the degree of thickness necessary
to prevent the shrinkage of the applied clay in the firing, from
revealing the body of the vase, still the beginner is very likely
to be deceived as to the thickness of the _impasto_, judging by the
eye alone. Potters dip pieces of ware in colored slips, and the
thickness of the covering thus formed is all sufficient. In the case
of painting, however, it is impossible to lay the clay on as evenly,
and there will be, in all probability, some places too thinly covered
to stand the fire, but which would not be revealed before. It is
better, therefore, to apply two coats, so that one may cover up the
deficiencies of the other. The reason for having these two coats of
different tints is, that it is then possible to be assured that the
surface is covered completely, it being easy to distinguish the first
tint laid from the body of the vase, and in the second painting, to
observe that it entirely covers the first.
The second coat finished, a lighter tint should be mixed, with which
the ground is varied by touches here and there, making the highest
light of the ground, while touches of the first tint mixed, give the
darker shades. There should be difference enough in tone between the
middle tints of the ground, and these lighter and darker tints, to
produce a good effect of light and shade, and these touches should
be laid on with a free hand, and then softened into the ground, care
being taken that the lights and shadows should not end too abruptly.
In these touches, as in all the painting, there must be a certain
thickness in reality, as well as in appearance, to make the work
effective when finished. The clay shrinks and seems to be dissipated
in the process of firing, and if applied too thinly, in any part,
will reveal the body of the ware, or some under-tint, perhaps
spoiling the appearance of the whole. The transparent effect,
produced by a thin layer of clay, which, after firing, shows the
under-tint through, is sometimes very beautiful in certain parts
of a design. It is, however, difficult to judge by the eye of the
requisite degree of thickness necessary to produce this effect, and
the heat of the firing may be so great as to cause that portion of
the painting to disappear entirely. It can not, then, be safely
counted upon, and the best way is to depend solely upon the lights
and shades of the painting for the effects desired.
The ground finished, the decorative design may be painted upon it.
This should not be outlined upon the surface, but should simply be
painted with a free hand, and without too much attention to detail, a
brilliant effect of light, shade, and color being the object aimed at
in this style of painting.
We will suppose that a floral design is to be painted upon the vase.
The middle tint of the flowers can first be laid, the shadows are
then put in, and lastly the high lights, laid on heavily, almost
giving the effect of relief. Leaves and other accessories of the
design may be treated in the same manner. The edge of the design
must be softened into the background, to avoid a hard effect after
the work is glazed. The process of glazing has a tendency to soften
and melt the tints into each other, but this effect must be enhanced
by judicious use of the middle tints and shadows of the painting,
and by leaving the edges thin. One of the greatest beauties of this
kind of painting, when well done, is the effect of the rich colors
melting into each other, with a charming indistinctness, which leaves
something to the imagination of the beholder.
Those who have not been accustomed to the use of color in such
masses, will, perhaps, be embarrassed at first by the difficulty of
painting with clay. This will soon be overcome by practice, but, as
has been said before, it should always be remembered that it is clay
which is used, and, therefore, the work is subject to the conditions
which govern the use of that material.
It is unnecessary to enter further into details, as it is only
intended here, to give some instruction as to the method of painting,
leaving the manner of it to the artist, it being taken for granted
that any one desiring to practice this kind of painting should have
already attained some proficiency in the use of colors, and should
have acquired a knowledge of the rules which govern art.
To such there will simply be the difficulty of learning to work with
a new material. If this knowledge does not exist, it will be no
easier to succeed in accomplishing any thing, worth the doing, in
this, than in other kinds of art work.
With regard to the colors to be used, it is enough to say that a
sufficient number can be obtained to produce by admixture, in various
degrees, tints for the production of any subject required. It is
only necessary to remember, as said before, that in these mixtures
the stronger colors must not be in such proportion as to overpower
the weaker. A list of useful colors has been given in a previous
chapter. In regard to the mixtures of these colors a few words may be
of use.
Black is a very useful color for shadows, making, in its admixture
with white clay, numerous pleasing tints of grey, which may be varied
by the addition of any other color which may be desired. As black is
one of the strongest colors, however, it must be very sparingly used
where a light tint is needed. In the mixture of blue and green, the
former must exist in a much smaller proportion than the latter, if
the mixture is to have a greenish tint. Experience alone can give
success, but enough has been said to prevent the beginner from making
very disastrous mistakes.
The painting must, of course, be executed while the clay is wet, and
should be finished in one sitting. If this is not possible, it may be
kept wet in the way described for keeping the ware before painting.
In describing the method of painting a vase, we have taken for our
model, one decorated with flowers. Decorations can, however, be
as varied in regard to subjects as paintings on canvas. Floral
decorations seem to be the best adapted to vases, or other objects
having rounded surfaces. Plaques and vases, such as pilgrim jars,
which afford flat surfaces, may also be decorated with landscapes
or figures. For these subjects somewhat different treatment may be
adopted, but enough has been said to indicate the requirements of the
material, and each artist will find a manner suited to himself.
Decorations of a similar character can be produced upon ware of
different colors, leaving the color of the clay for a ground. This
has a very good effect when done upon cream-tinted clay in suitable
colors. As this kind of ware should be fired at a higher temperature
than the deeper tinted and coarser clays, the colors are liable to
fade in the firing. This is not undesirable, however, as the faded
tints harmonize with the light ground much better than darker colors.
Some beautiful effects can be produced by decoration of this kind,
which can be supplemented by carving and gilding.
The same method can be used on a ground of dark red clay by the
selection of colors which will harmonize with the ground. Yellow
flowers look well upon a ground of this character, and the yellow
color can be produced, as we have said before, by the use of yellow
clay, either alone or as an adjunct to the color.
Monochrome decorations can also be produced, by the use of natural
clays of various colors, in the same manner as that pursued in the
use of the artificially tinted clay of which we have been treating.
Good effects can be produced in this way, with the advantage that the
colors will be fully retained in the firing. Red, or brown and white,
in various degrees of combination, can be used to produce a design
with every effect of light and shade. Also, red, with cream-tinted
clay, or the three colors—red, yellow and white—can be used together.
These designs can be produced upon grounds of cream, red, or yellow
clay.
DRYING.
When the painting has been completed, it should dry very slowly, and
it would be better, if possible, to effect this by placing it in a
moist, cool place. It is, however, difficult to handle a piece of
ware when wet. The clay is in a very soft state, and a sudden jar
might cause the vase to fall to pieces.
If the vase has not been in proper condition for painting, or has
dried too quickly, it will, after some hours have elapsed, begin
to show fine cracks upon the surface of the painting. These may be
stopped, before they have gone too far, by passing a modeling tool
over them, or, if the crack has become too deep for this treatment,
it may be filled with clay as nearly as possible in the state at
which the body of the ware has arrived. If the cracks are allowed
to go too far it will be difficult to stop them, as they may have
extended into the body of the ware.
If the piece is permitted to go to the firing with any cracks,
however small upon its surface, they will become widened in the
firing, and, especially after the glazing, will show very distinctly.
In the biscuit, they may be stopped by filling them with powdered
clay mixed with gum water. But an ounce of prevention is worth a
pound of cure, and the safest method is to prevent their appearance
in the first place. If this can not be done, they must be stopped as
soon as they appear. The finer clays seem to have a greater tendency
to crack in drying, and when the cracks have appeared, they are more
difficult to stop than in other clays.
FIRING.
When the piece decorated is thoroughly dry, it should be fired at a
temperature sufficient to make the body durable, and at the same time
to perfectly fix the colors of the painting, so that there may be no
danger that the glaze will cause them to run in the final firing.
This latter defect may also result from an excess of glaze, and where
it exists only in a very slight degree, produces a melting softness
which is very pleasing. This effect is, however, so likely to be
exaggerated to the ruin of the work that it is best not to run any
risk of the kind in firing, and to depend upon the painting alone for
the harmonious blending of the tints.
The temperature at which the work is to be fired, must, of course,
depend upon the qualities of the clay of which the piece of ware is
made. As has been said before, this clay should be one that does
not require an excessive degree of heat in firing. The exact degree
can be estimated by the potter who understands the requirements of
the clay which has been used in the manufacture of the particular
piece of ware in question. It may be said that the temperature at
which Rockingham ware is fired is suitable for this work, and that a
glaze such as that used upon that kind of ware can be used with good
results. It is possible to have a glaze so adapted to the body of the
ware as to prevent it from crazing, and yet preserve the brilliancy
of the colors.