Title: Pottery decoration under the glaze
Author: McLaughlin, M. Louise
Language: English
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  POTTERY DECORATION

  UNDER THE GLAZE.

  BY
  M. LOUISE McLAUGHLIN.


  CINCINNATI:
  ROBERT CLARKE & CO.
  1880.



  COPYRIGHT.
  M. LOUISE McLAUGHLIN.
  1880.



  CONTENTS.

  PREFACE.            v
  INTRODUCTION.     vii
  CHAPTER I.       xiii
  CHAPTER II.        28
  CHAPTER III.       36
  CHAPTER IV.        41
  CHAPTER V.         68
  CHAPTER VI.        79
  CHAPTER VII.       85



PREFACE.


It has been with some hesitation that I have undertaken to write a
manual on the decoration of pottery under the glaze. This feeling was
caused by the fear that I should not be able to treat the subject in
as comprehensive, as well as comprehensible, a manner as it deserved.

Nevertheless, in an experience of more than two years, chiefly spent
in experimenting on different methods of under-glaze decoration, I
have learned some things which may be of use to others, and have
thought that a treatise upon the subject from an unprofessional,
yet practical standpoint, might have its place in the literature of
ceramics which has now become so extensive.

Let it be understood, however, that in the following pages there has
been no attempt to deal with the occult mysteries of the potter’s
art, but simply to give an account of results attained and facts
acquired, every one of which can be vouched for as a record of actual
experience.

I would like here to express my sense of indebtedness to the potters
who have, by their courtesy and attention, contributed to these
results, and particularly to Mr. Joseph Bailey, Sr., of the pottery
of Mr. Frederick Dallas, whose intelligent co-operation and valuable
advice have been of the greatest service.

  _Walnut Hills.
  Cincinnati, May, 1880._



INTRODUCTION.


The decoration of pottery under the glaze offers opportunity for the
production of work, beautiful and artistic in a high degree, and in
its simpler forms gives to those who do not aspire to the higher art,
a most fascinating and labor-rewarding study. I can not, however,
assure those who wish to enter the domain of decorative art by this
interesting road, that they will find the way strewn with roses.
On the contrary, discouragements are likely to occur so frequently
that it is only by the exercise of a considerable amount of patience
and perseverance that any advance can be made. But such are the
attractions of the work that its enthusiastic votaries will not be
deterred from its prosecution by any difficulties in the way, and
if immediate and perfect success can not be assured, an exceedingly
interesting occupation will be revealed to the learner, and to the
earnest worker can be promised the reward of faithful labor.

I would like here to insist, however, upon the necessity of a
thorough and serious study of drawing as a preparation for this as
well as for all decorative work, and to enter a most emphatic protest
against the theory which seems to prevail in some quarters, that
any one can paint upon pottery acceptably. With little preparation
other than the possession of some colors, brushes, clays, and pieces
of pottery, the devotee of art enters upon the work of decorating
(?) pottery. Alas! disfiguring it, for it is a lamentable fact that
of the pottery now being painted by amateurs (some of the work
by professional decorators might also be included) a very large
proportion has its value diminished rather than enhanced by the work
put upon it.

This would not be so frequently the case if the scope of the work
were limited to the capacity of the worker. We see every day,
attempts, in which the failure to reach the point aimed at is
absurdly obvious, where, if the effort had been less ambitious in its
aim, the result would not only be less an object of ridicule, but of
far more intrinsic value.

In other departments of human handiwork, some natural capacity,
as well as a certain amount of training, is considered necessary
to successful practice, but, in art, such is the ignorance of the
general public, any one is thought eligible to the profession of an
artist, and much passes under the name of art, which has no claim to
that honorable title.

I do not wish to discourage those who are willing to enter into this
pursuit as humble, patient learners, but to warn those, who are eager
to obtain at once the rewards only given to years of faithful study,
of the futility of their desires. It is perhaps idle, however, to
warn or to advise them. The consciousness of their folly will only
come to them after experience, and knowledge gained from failure,
shall have given them some comprehension of the difficulties which
their ignorance prevented them from seeing.

In art, as in all other pursuits, there is no royal road to
excellence, and those who do not think it necessary to learn the
rudiments before attempting the higher branches, will learn to their
cost, if they are capable of learning any thing, that nothing was
gained by leaving out these stepping stones in their progress.

The time is never misspent which is devoted to honest, well-directed
efforts in acquiring the art of drawing. The excuse so often offered,
that the practice of the art is only intended as an amusement, and
that therefore it is unnecessary to undergo the drudgery of learning
it thoroughly, is one which is unworthy. To those who offer it I
would say, pray amuse yourselves with something else rather than an
art, into which, to obtain even an insight, demands the best that any
one can give.

These remarks apply as well to the decoration of pottery as to any
other department of art work. Although from its peculiar nature and
various uses this material yields itself to many and varied styles of
decoration, yet this decoration, however simple, must be planned and
executed according to sound principles, to be of any artistic value.
The best preparation for the work of decorating pottery, therefore,
is a thorough knowledge of drawing and an understanding of the laws
which govern all decorative art.

Sources of information upon these subjects, drawn from competent
instruction, books and periodicals, are daily becoming more numerous
and accessible, and one who desires to practice the kind of
decorative art we are now considering, should cultivate his taste
and augment his skill by these means, and especially by close study
of nature in all its various forms. It is only in this way that the
student will be enabled to accomplish work which will be a source of
pleasure and profit to himself and others.



POTTERY DECORATION UNDER THE GLAZE.



CHAPTER I.

POTTERY.


We will consider in this chapter some facts in regard to pottery,
which, although of a very elementary character, are not so generally
understood as may be desirable. These facts relate to the substances
of which pottery is composed, the processes of its manufacture, and
the methods by which it is or can be decorated.

Two chemical substances, viz., silica and alumina form the basis of
all pottery clays. These substances are themselves infusible (except
under the compound blow-pipe), but by admixture with other materials
more susceptible to the action of heat, they are made useful to the
potter’s art, and, when subjected to a high temperature, fuse and
form the hard, insoluable combination with which we are all familiar.

Porcelain, and the finer kinds of earthen-ware, are made from clays
artificially combined of various natural elements, in such a manner
as to produce the qualities desired, while the coarser wares are
generally made from clays in a natural or unmixed state. These clays
agree in their essential characteristics, but contain other elements
which cause certain differences of color, susceptibility to heat,
plasticity, etc. The differences, therefore, which exist between the
many kinds of pottery manufactured, may be said to be due, not so
much to a diversity of the materials used, as to the changes produced
by the combination of the same materials in varying proportions.

It is unnecessary that we should here enter into the details of the
mixture of different pottery clays, for which each manufactory has
its own formula. A few words, indicating, in a general way, the
causes of certain easily-recognizable qualities, will suffice.

The peculiar beauty and translucency of fine porcelain, is due
to an excess of silica, or the vitreous element of pottery, in
its composition. This is attained by the use of kaolin, a fine,
white clay, produced through the agency of natural causes in the
decomposition of feldspar, which is itself a silicate of alumina, and
one of the principal ingredients of granitic rocks. In porcelain, it
may be said, that the proportion of silica to alumina is about three
to one, and the other ingredients, such as iron, potash, chalk, and
soda, exist only in such quantities as are necessary to cause the
fusion of the two first-mentioned elements. It is fired but slightly
the first time. This leaves the body of the ware very soft and
porous, and upon the application of the glaze the latter is absorbed
into the body, and by its action upon the materials composing it,
produces a translucent effect.

We refer, here, to French porcelain. In the manufacture of English
china, the process is radically different. The last-mentioned ware
is sometime spoken of as “bone china.” This term has reference to
the use of bones from which the lime required in its manufacture is
obtained. This element produces a translucent quality in the body of
the ware independently of the action of the glaze, which in this case
forms merely a coating upon the surface of the previously hard baked
body.

Earthenware possesses less of the vitreous element, and the first
firing is continued until the ware becomes so dense that it will not
absorb the glaze, and the body remains opaque.

The term pottery, is more strictly applicable to the kind of ware
last mentioned. It is to this that especial reference will be made
in the following pages, in describing methods of manufacture and
decoration.

Earthenware is of various colors, ranging from pure white, through
the cream white and cream-colored wares to decided yellow, and lastly
red. The clays can also be artificially colored, and changes in color
are also produced by different degrees of temperature in firing.
Ordinarily the process of firing produces a material change in the
color of clay. Thus, a grey-tinted clay will assume a bright, yellow
color, and a dull brown, green, or blue will be changed to a bright
brick-red, under the action of the fire.

The heat used in firing should produce partial vitrification. If a
piece of ware has not been fired sufficiently to produce that effect,
it is said to be “soft-baked.”

White earthenware requires the greatest degree of heat in firing. In
regard to the wares made from clays retaining the colors produced by
the elements which they contain, in a natural state, it may be said
that the amount of heat necessary for proper firing, decreases with
the depth of color. This rule, although it may accurately indicate
the temperature at which any given clay should be fired, is simply
artificial, except in so far as the depth of color shows the presence
of an amount of foreign matter, which by its action increases the
fusibility of the clay.

Red clay, being very susceptible to heat, is commonly used as a test
in the firing of white ware. The same clay will change in the process
from light red to dark brown, and so enable the experienced fireman
to determine the degree of heat existing in the kiln.

Clays should be prepared for the making of pottery by careful
sifting, dissolving in water, and, as a final precaution, straining
through sieves made of fine, silk lawn. In this way all foreign
particles are removed, and the clay, having attained the consistency
of dough, is ready to be molded into the shapes desired. This is done
in molds made of plaster of paris, or it is “thrown” by the hands of
the potter on a turning-wheel, or, again, by a combination of these
processes.

Before firing, the ware is said to be in the “green state,” in which
condition it passes from “wet” to “hard green,” and finally to
“white,” when it is ready to be fired. If fired before it has become
sufficiently dry, it will be liable to crack, or scale, from the
sudden expansion of the moisture confined in the clay. When dry, it
is placed in “seggars,” or boxes, made of fire-clay, which are piled
upon each other in a kiln, constructed for the purpose of firing the
ware.

During the process of drying and firing, the clay loses a certain
portion of its bulk. The amount of this shrinkage varies in different
clays, but ordinarily may be said to be about one-eighth. A piece
of ware, therefore, made from clay which exhibits this degree of
shrinkage, would be one-eighth smaller after firing than before.
The shrinkage is also modified by the degree of heat to which the
clay has been subjected in firing, and there will sometimes be a
perceptible difference in the size of two pieces of ware, made from
the same clay, and of equal size before firing, after having been
fired at different temperatures.

The length of time consumed in firing, varies with the qualities of
the different wares. In the manufacture of white earthenware, the
firing lasts from thirty to forty hours, while the more common kinds
of ware require less time. In kilns of ordinary size, a thousand
dozen pieces of ware are frequently fired at once. Of course,
considerable time is required to place the seggars containing the
ware in the kiln. Some hours must elapse before the kiln and its
contents will become cool enough to permit its being opened with
safety, so that the firing of hard-baked pottery may require two or
three days for its completion.

The first firing completed, the ware is said to be in the “biscuit,”
and is then ready to be glazed. This matter of glazing is a very
important one, and the success of the whole very largely depends
upon the manner in which the operation is performed. To insure
a successful result there must be the nicest adaptation of the
materials composing the glaze to the body of the ware. The glaze for
each kind of ware must be suited to its especial characteristics, and
it can therefore be imagined that the number of glazes in use is very
large. Each pottery has its own glaze and the variety is infinite.

The glaze used upon the finer kinds of earthenware consists of
materials similar to those of which the body of the ware is made,
with the addition of boracic acid (a powerful flux), which with a
little lead renders the glaze fusible. In the lower grades of ware a
larger amount of lead is used for a flux, and this causes the glaze
to fuse at the comparatively low temperature at which these wares
are fired. A glaze made of materials that fuse at an unusually low
temperature is called a “soft” glaze. Some glazes are so soft that,
when fired, they can be easily scratched by the point of a steel
instrument. The glaze of good and durable wares is, however, so hard,
that the point of the sharpest knife will make no impression on its
surface.

The materials of which the glaze is made, are combined in the proper
proportions and diluted to form a liquid of about the consistency and
the appearance of cream. The piece of ware is then dipped carefully
into the liquid, and so skillfully manipulated that it is completely
covered with a coating of the glaze of the necessary thickness.

After having been covered with the glaze, which, before firing, has
the appearance of an opaque white paint, the ware is ready for the
second firing. This is done in what is called the “gloss” kiln, in
which the heat is not brought to such a high degree as in the biscuit
kiln, but is sufficient to fuse the glaze, and cause it to form a
glassy, transparent surface, which should completely cover the body
of the ware, and present an equally brilliant appearance in every
part.

If the glaze is not suited to the body of the ware, and does not
shrink equally with it, its surface will soon present a network of
fine cracks. A glaze in this condition is said to be “crazed.” This,
among potters, is considered a serious fault, and in ware intended
for cooking or table use, is certainly very undesirable.

Old Japanese crackle-ware, in which this condition is a
distinguishing feature, is, however, much esteemed, and many, indeed,
the majority of the Japanese earthernwares, both ancient and modern,
display a surface of fine-crackled glaze, which may not be said to
detract from their value as articles of ornament.

A similar effect is also seen in old pieces of glazed ware which have
seen long service as cooking utensils, in which case it has been the
natural result of the usage to which they have been subjected.

In some modern wares, both French and English, decorated under
the glaze, this defect is seen. In these cases it has been caused
by the use of a softer glaze than the body of the ware demanded.
This expedient has been resorted to in order that the brilliancy
and beauty of the colors might be preserved. These articles being
intended only for ornament, beauty is more of an object than
durability, and this defect of glaze may be permissible as the means
of obtaining more brilliant effects. In certain methods of decoration
this may be a necessity, but these cases are exceptional and
experience leads me to believe that it is possible to obtain beauty
of coloring with a glaze which will remain intact. It is to be
hoped, however, that with the improvements in making colors the time
may come when it will be possible to obtain colors which will retain
their beauty under the degree of heat necessary to the production of
an article which a practical potter would call a perfect piece of
ware.

Pottery can be decorated either _under_ the glaze, _with the glaze_,
as in the case of majolica, in which the color is effected by the
use of colored glazes and in the decoration of soft porcelain
(_pâte-tendre_), where the painting is executed upon the unbaked
glaze, and, lastly, _over_ the glaze. We will concern ourselves only
with the first of these methods. A few words, however, may not be
out of place here, upon the differences between over and under glaze
painting, which are frequently compared and as frequently mistaken
for each other.

_Over_-glaze painting, as is well known, is executed upon the glazed
surface of the finished ware with vitrifiable colors having enough
flux or fusible material in their composition to cause them to
fuse at a comparatively low temperature, and so become attached
to the glaze. _Under_-glaze decoration is effected by the use of
colors which contain less flux, and consequently require a higher
temperature for their fusion. It can be executed either upon the
ware in the “green” state, or, as is more commonly the case, in the
biscuit. These two methods of painting differ materially in their
effects. Any one familiar with these effects can readily discover
whether a piece of pottery has been decorated over or under the
glaze. Those who are not practically conversant with the two methods
can be easily misled, and mistakes are frequently made by those who
should know better, as to the method employed in the case of a piece
of ware in question.

A certain delicacy of tint and firmness of outline characterizes
overglaze painting, which is easily recognized by experts, but those
who can not distinguish between the two methods by this means may
ascertain to which class the decoration belongs by looking aslant
the surface. The glaze upon the painted portions of a piece of ware
decorated over the glaze, will not, even after the most perfect
firing, equal the glaze upon the uncovered portions in brilliancy,
and there will probably be certain inequalities of surface between
the painted and unpainted parts which will be revealed to the touch.

If the decoration has been executed under the glaze the surface will
be uniformly covered with a brilliant glaze. Of the two, underglaze
painting is probably the most difficult, as the colors are more
liable to change under the action of the great heat to which the ware
must be subjected, and the final results being, therefore, somewhat
uncertain, can not be accurately counted upon, until experience has
been gained from repeated failures. On the other hand, overglaze
painting, while not subject to the changes produced by the fire, to
so great an extent, is more difficult as regards the manipulation
of the painting upon the glazed surface. The facilities for the
practice of overglaze painting are greater than those afforded for
painting under the glaze, which last, requires not only the handling
of an artist who has acquired facile use of the brush and some
experience of pottery clays and colors, but also the assistance of an
intelligent and skillful potter.

Let us not, however, laud one method of painting at the expense of
the other. Both are good in their way, and confined within their
proper limits, have beauties peculiarly their own. Overglaze painting
possesses a delicacy of effect and a variety of color which the
underglaze decoration can not rival. The latter is, however, the most
artistic as well as the most effective, and lends itself more readily
to the uses of decorative art and to the modern taste in color.

It is this latter method of decorating pottery which we will now
consider in some of its various forms.



CHAPTER II.

COLORS FOR PAINTING UNDER THE GLAZE.


Colors for painting under the glaze are specially prepared for the
purpose from various metallic oxyds. As mentioned in the previous
chapter, the colors used under the glaze have less flux or fusible
matter in their composition than those used for painting overglaze:
this is necessary, because in the former the colors are expected to
bear a much greater degree of heat in firing than in the latter. They
are so prepared as not to fuse except at the temperature required in
the manufacture of the pottery to which they are applied. The variety
of underglaze colors is less than that to be found in overglaze
colors, as the oxyds from which colors may be made which will stand
so great a degree of heat, are few in number.

The oxyds from which the colors are prepared are called the bases of
these colors. The colors used in underglaze painting are made from
the following bases:

Blue from the oxyd of cobalt. Co. O.

Green from the sesquioxyd of chromium. Cr^2. O^3.

Browns from the sesquioxyd commonly called the peroxyd of iron, Fe^2.
O^3., and from the sesquioxyd of manganese. Mn^2. O^3.

Yellow from the compound of titanium with oxygen, called titanic
acid. Ti. O^2.

Black from the oxyd of uranium.

Red from the suboxyd, or red oxyd of copper. Cu^2. O.

We may add, upon the authority of M. Debette, that “pure black is
obtained by taking 1 part of oxyd of uranium diluted in 22 parts of
glaze; ordinary black with oxyd of manganese or oxyd of iridium;
bluish black with a mixture of oxyd of cobalt and of manganese, and
smoky grey with chloride of platinum. Rose is obtained by diluting,
in glaze, gold which has been dissolved in aqua regia. For the blues,
oxyd of zinc and alumina may be mixed with the oxyd of cobalt. For
greens may be mixed oxyd of cobalt and oxyd of chromium.”

The fluxes used for these bases are given in the following
paragraphs, translated from the _Encyclopédie-Roret_:

“The matters which enter into the composition of the fluxes and which
cause the adherence of the metallic oxyds are quartz, feldspar, borax
and boracic acid, nitre, the carbonates of potash and of soda, red
lead and litharge, and oxyd of bismuth. At Sevres, they employ, for
under-glaze painting, seven kinds of fluxes, which suffice for all
the colors. The majority of these fluxes are composed of quartz,
oxyd of red lead and of boracic acid, and to some is added a small
quantity of carbonate of soda.

“The seven fluxes of Sevres are, first, the flint flux, which is
prepared by melting quickly in a crucible and then flowing upon a
metallic plate a mixture of 3 parts of red lead or of litharge, and 1
part of Etampes sand.

“Second. The flux of greys prepared with 6 parts of red lead or
litharge, 2 parts of Etampes sand, and 1 part of pulverized borax.

“Third. The flux of carmines is made of 1 part red lead, 3 parts of
Etampes sand, and 5 parts of pulverized borax.

“Fourth. The flux of purple is made with 3 parts of red lead or of
litharge, 1 part of Etampes sand, and 5 parts of crystallized boracic
acid.

“Fifth. The flux of violets is made of 27 parts of litharge or red
lead, 2 parts of Etampes sand, and 11 parts of crystallized boracic
acid.

“Sixth. The flux of greens employed, as well as the two preceding
M. Salvetat, was prepared by him with 8 1-9 parts of red lead or
litharge, 1 part of Etampes sand, and 2 parts of crystallized boracic
acid.

“Seventh. Last the flux of the metallic substances, which is of
sub-nitrate of bismuth, obtained by decomposing in water the nitrate
of the acid of bismuth, to which is added 1-12 of borax.”

These fluxes are mixed with the basic oxyds in greater or less
proportion, according as the colors are intended for work, which will
require a greater or less degree of heat in firing.

Underglaze colors in powder suitable for painting on pottery, can
be procured of several different manufactures. As mentioned before,
the variety of these colors is not so great as is to be found in
overglaze colors, but as they can be readily mixed the number is
sufficient for all practical purposes.

In my own work I have made almost exclusive use of French colors,
those manufactured by M. Lacroix. These colors are finely ground and
of considerable variety of tint. A list of those which have been
tried and found to give satisfactory results, may be given here:

  Blues—_Bleu de Roi_ (King’s blue).
         _Bleu violacé_  (violet blue).

  Light blue—_Bleu myosotis_ (Forget-me-not blue).

  Reds—_Rouge T._ (Red T.) and _Rouge P. W._

  Carmine—_Rose_ (or Pink).

  Greens—_Vert foncé_, No. 1 (dark green).
          _Vert tendre_ (light green).

  Black—_Noir_.

  Browns—_Brun foncé_ (dark brown).
          _Brun_ No. 5 (Brown No. 5).
          _Brun jaune_ (yellow brown).

  Yellow—_Jaune foncé_ (dark yellow).

  Grey—_Gris clair_ (light grey).

There are many others, but these are mentioned as among those that
have been tried and found to fire well, and the colors given in this
list will be sufficient for the production of all the tints needed in
underglaze painting. In faience painted after the Haviland method,
fine white clay takes the place of white.

In painting on the biscuit white paint is sometimes used. This can
be procured of English manufacture, but is not, I believe, made
by M. Lacroix. The colors manufactured by Messrs. Hancock & Sons,
Worcester, England, are also very satisfactory. The tints of these
and the colors of other English manufacturers corresponds with those
of M. Lacroix, which have been mentioned. The latter manufacturer,
however, furnishes a much greater variety of colors, and the reds
especially are superior to any English reds I have seen. M. Lacroix’s
list includes at least three reds, one of which, _Rouge T._, can be
relied upon to produce as good a scarlet as is possible under the
glaze, when used under the proper conditions. The English carmines
are very satisfactory. The English green, called French green,
corresponds in tint to that of M. Lacroix, called _Vert foncé_, No.
1, while mazarine blue, of the Worcester and Phillips manufactures,
and Cobalt blue of others corresponds to the _Bleu de Roi_ of the
French, and for work on biscuit white ware stands the fire rather
better. The Victoria green, of the Worcester colors, is especially to
be commended for a light green which stands the fire remarkably well.

Phillips’ English colors are also very good. His mazarine blue,
especially, is one of the finest blues I have ever met with. Emery’s
and Harrison’s colors fire very well, but are not so finely ground as
the first mentioned.

[Illustration: Decoration]



CHAPTER III.

PAINTING ON POTTERY AFTER THE MANNER OF THE HAVILAND OR LIMOGES
FAIENCE.


This method of painting on pottery is said to have been discovered
by M. Laurin, at _Bourg-la-reine_, in the year 1873. The process
was afterward adopted by M. Haviland, and by him improved in such
manner as to materially change the method, as well as the appearance
of the painting. Specimens of the ware were first exhibited at
the Centennial Exhibition, in Philadelphia, in 1876. The first
application of a similar style in the decoration of pottery, in this
country, was made by the writer in Cincinnati, in October, 1877.

This method of decorating pottery, although not involving the use
of any new principle, was yet so entirely novel an application of
principles already in use, as to entitle M. Laurin to all the credit
attaching to a very original and important discovery. It places in
the hands of the painter of pottery a method at once so artistic,
and so thoroughly in accord with the modern school, as to awaken a
profound interest in the minds of all lovers of art. It is probable
that there are capabilities in this art that have not yet been
brought out. It is still in its infancy, and that there are in it
possibilities of much importance to the artistic world, can hardly be
doubted.

If it were not for the technical difficulties which surround all work
on pottery, and this style in particular, it would offer facilities
for the production of works of art unequaled by any method heretofore
in use. It is the hope of the writer that the following description
of the method of decorating pottery, in this manner, may throw some
light upon these technical difficulties, and also that artists of
ability may be induced to try it, and so demonstrate the capability
it undoubtedly possesses.

The mere knowledge of the materials used will, however, no more
produce artistic work, than a box of Winsor & Newton’s colors, in
the hands of a beginner, will enable him to paint a picture, equal
to one by Titian. To produce good work in this method, there must be
a certain amount of skill at the command of the painter, just as the
same degree of skill is requisite in the production of a good picture
by any other method. There is a certain boldness of effect produced
by the very nature of the materials and process, which probably would
not be seen in the work of the same person in other methods, yet the
lack of artistic feeling and ability will be as painfully apparent in
this as in any other.

Colors may be daubed upon pottery, as they are, alas! upon canvas,
by those whose training and whose feeling for art would hardly fit
them to become good house painters; but the result will not be good
art, nor will it ever be its own excuse for being. If other branches
of decorative art require taste, knowledge, and practical skill,
so much the more does this, when it offers scope for the highest
capacity. To the artist of ability sufficient to make use of it, it
furnishes a palette which, although not of the same range as that of
oil colors, yet affords an almost unlimited scale of colors, each
of which is enhanced to the fullest degree by the brilliant glaze,
with which the work is finished. The painting executed with these
beautiful colors, moreover, is practically unchangeable, and none of
the ravages of time, short of the destruction of the piece of ware
itself, can affect it. In decorations for buildings, or for ordinary
use in portraiture, or the higher forms of art, it offers, what has
long been desired among artists and art lovers, a method of making
works of art indestructible and beyond the possibility of change.

The ware known among dealers under the name of “barbotine,” has some
resemblance to that which we have been considering. It has a light
body, which has been subjected to a very slight fire, and is covered
with a soft glaze, which ensures great brilliancy of coloring. The
ware, however, has no durability, and is a substance that would not
stand the action of the elements, if used in external decoration.

[Illustration: Decoration]



CHAPTER IV.

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.



CHAPTER V.

MODELING IN RELIEF.


Under this head may be comprised the decorative modeling of figures
and other designs upon pottery, in various degrees of relief. First,
we have figures in relief forming decorations upon vases. These,
as well as other designs in high relief, belong properly to the
domain of sculpture, and the methods of producing them do not vary
essentially from those in use in that art. The final process in this
case is the firing, instead of the casting in plaster and cutting in
marble.

Of the methods of producing floral designs in relief, a few
suggestions may be of use. These, as well as the painting described
in the previous chapter, must be executed when the body of clay, to
which they are applied, is very wet, and the applied clay must in
this case be, as nearly as possible, in the same condition. If the
clay is not in the proper condition, the work will crack in drying.

The vase which is to be decorated being in the right state, a lump of
clay, having the plasticity necessary for modeling, is procured. This
may be of C. C., a deeper cream color, or red, according to the color
desired. White granite is not plastic enough, and is, besides, liable
to crack in drying. But of all white clays, parian forms the most
beautiful substance for this kind of modeling. Leaves and petals of
flowers can be shaped from pieces of clay, which have been flattened
to the required thickness, either by pressing upon a slab of plaster
of paris, by means of a weight, such as potters use; or, if the work
is not on a large scale, the clay can be shaped in the palm of the
hand. The forms can then be cut with a sharp modeling tool. If there
is more moisture in these pieces of clay than in that which forms the
body of the vase, they should be allowed to remain a short time upon
a dry plaster slab. The plaster will quickly absorb the moisture in
the clay. When ready, the pieces can be placed in position on the
vase, the places where they are to be applied having been previously
washed with clay and water (technically called “slip”), or with
glaze water, to make them adhere. Stems are made by rolling pieces
of clay between the palms of the hands, or upon a flat surface of
wet plaster or wood. They are afterwards allowed to dry, and when
in proper condition, applied in the same manner as the flowers and
leaves. Delicate touches may be put in with a brush dipped in clay,
of a proper consistency for painting. The forms of the design can be
shaped and finished after they have been applied to the vase by the
use of modeling tools, and, finally, with a camel’s-hair brush. The
design may also be brushed over with a sponge, moistened with water,
which will also be found very useful in restoring the smooth surface
of the ground, if it has been injured in the process of modeling.

After the modeling has been completed, the work should be gone over
with a modeling tool, and in places where a mass of clay has been
attached to the surface, the edges should be under-cut. This will
prevent cracking. If this precaution is not taken, a crack thus
produced may extend into the body of the vase and render it unfit for
firing. Where a large mass of clay occurs in the modeled design, it
is better to hollow out the projection from the inside of the vase,
to prevent the cracking or warping of the whole in firing, caused by
the unequal thickness.

Cracks, which may appear in drying, should be filled, or, if
possible, be pressed out with a modeling tool, before the piece is
fired. If the crack is so deep that it is necessary to fill it, the
place should be cut open with a modeling tool, moistened with water,
and filled with clay, as nearly as possible in the same condition as
that upon the vase.

Flowers can be modeled in parian clay upon a creamy-tinted ground
with good effect. Various colors of deeper tinted natural clays, or
clay which has been artificially colored in the body, can be used as
the ground of such decorations. Light grounds are sometimes colored
after the first firing, in the biscuit; or a ground can be painted
in the method described in the previous chapter, while the vase is
soft, and the modeled decoration can then be applied instead of the
painting.

Decorations of this character in high relief are frequently colored
in natural tints, either under the glaze, in the biscuit; or over the
glaze. The taste of this manner of finishing relief-work is somewhat
questionable, and the same objection might apply to it as to colored
sculpture. That it has received the sanction of the best factories in
the world is no proof of its being in accord with correct taste, as
the many (artistic) atrocities of Dresden and Capo di Monte testify.
Some of the later Haviland faience, however, having a ground in the
usual style of that ware with decoration in high relief, colored
with subdued tints, harmonizing with the grounds, is so artistically
done that one can hardly think it open to this objection, although it
can not be considered an improvement upon the earlier work of this
establishment in which the colored decorations were simply painted
upon the surface.

It is only to the use of colors which imitate those of nature upon
modeled decorations that there could be any objection. Relief-work
may be conventional in its form, or colored conventionally, in one
color or many, or gilded, with perfect taste. The latter method
produces a fine effect, but, to make it successful, the color of the
ground should be well chosen, and the design simple in form and not
too much detached from the surface. The gilding looks best when left
unburnished, and should only be rubbed enough to give the effect of
dead gold.

Next, we have applied designs in low relief. These are made in
several different ways, according to the effects desired. Work of
this kind is more commonly executed by the method used in the
production of Wedgwood-ware. The designs to be applied are first
modeled in clay. Casts are then taken of the models in plaster of
paris. Clay of the kind desired for the relief designs is then
pressed in the mold and the edges trimmed off. The design can be
removed from the mold by the aid of a flat, steel instrument, with
a short, broad blade; or a palette knife, which when pressed upon
the clay adheres to it and detaches it from the mold. It can then be
transferred to the piece of ware to be decorated, to which it is made
to adhere by the use of “slip,” as described before.

This method is very useful, indeed, indispensable in the manufacture
of such wares commercially, when the same designs are to be repeated
many times, but it is hardly to be recommended for artistic work,
except for conventional designs, borders, etc. This method of casting
the forms in a mold may be useful, however, in the reproduction of
leaves of intricate outline, which can be made of various sizes,
and, from the plasticity of the clay, can be infinitely varied in
position according to the taste of the worker.

When objects of delicate and intricate form, such as threads,
spider’s webs, nets, and sometimes leaves, are to be represented in
work of this character, it can be accomplished by dipping threads, or
nets of cotton, or, if leaves, the natural leaves themselves, into
“slip.” The clay adheres to the threads, or forms, and after it has
set sufficiently, they can be placed upon the object to be decorated.
On firing, the substance inclosed within the clay is dissipated and
the clay only, remains. Some very wonderful and beautiful effects may
be produced in this way; but, as these delicate forms are necessarily
very fragile, especially if much detached from the surface, they are
only suitable for articles intended solely for ornament.

Designs in low relief can also be applied with the brush in the
forms desired, which may afterward be shaped and finished by the
use of modeling tools, or, when dry, carved with steel instruments.
This latter is said to be the method by which M. Solon executes his
exquisite designs in fine white clay upon ware which has been colored
in the body. One of the greatest beauties of M. Solon’s work is the
transparent effect produced where the clay has been left so thin as
to show the colored ground through.

Work in the very slightest relief can be done with the brush alone.
Care must be observed in this, however, that the application of
clay is not so very slight as to produce complete transparency upon
firing. By a judicious mixture of work in which the clay is so
heavily laid on as to remain opaque after the firing, and of that
which is applied so thinly as to become transparent, very delicate
and beautiful effects can be produced by the use of white clay upon
colored grounds.

The colored grounds in the Wedgwood and Solon ware are produced by
the use of a fine clay body, which has been artificially colored
throughout, which, in the case of Wedgwood, is finished by a very
slight glaze, and in the Solon ware, by a full glaze, by which
the transparent effects of certain parts of the work are brought
out. The colors used in the body of these wares are blues, dark
greens, and olives, and also black. Where it is not possible for the
amateur, for whom these hints are written, to obtain such wares for
decoration, very pretty work can be produced, as has been mentioned
before, by the use of a body of naturally colored clay upon which
white or a light-colored clay can be applied.

Relief-work can be finished with a full glaze, a very slight glaze,
or can be left unglazed. As a general thing it may be said that
the modeling in a design in high relief will look best with but a
slight glaze, or none at all. The slight glaze is called by potters
a “smear” glaze, and is effected by firing the work in a “seggar,”
which is glazed upon the inside. The unglazed ware absorbs enough
glaze from the glazed surface to give it a semi-glazed appearance,
which is very pleasing. Work in partial relief, as well as articles
in full relief, can also be finished by the application of colored
glazes. This is the method by which the ware known at the present
time as majolica is produced. Blue and green glazes of this kind
are frequently to be obtained in potteries in this country, where
they may be applied to work which has been modeled. Other colors in
majolica glazes are to be had from the dealers, and if the colors
desired can not be applied at the pottery, the artist can apply them
with a brush in the same manner as paint is used upon the biscuit.
The effect of work of this kind can also be enhanced by gilding put
on over the glaze.



CHAPTER VI.

INCISING AND CARVING IN CLAY.


These are two of the simplest as well as most effective methods of
decorating pottery. We will treat first of incised work in clay.

The piece of ware to be decorated must, of course, be in the “green”
state; not too wet, yet not dry enough to be brittle. An outline
drawing can then be executed upon its surface with a pointed modeling
tool, not too sharp, and perfectly rounded at the point. If any burr
is thrown up in the course of the lines, it must not be brushed off
until the piece has become partially dry. The drawing can then be
brushed over with a stiff camel’s-hair brush, leaving the lines
free. These lines can now be filled with dark (under-glaze) paint
(black is best), mixed with a little gum arabic and water. In going
over the lines some of the paint will extend over the edges; this can
be scraped off, when the clay is dry, with the edge of a sharp steel
blade, two or three inches long, held between the fingers and thumb.
A broken knife-blade will do for the purpose. This scraping must be
very lightly and carefully done, to avoid injuring the surface of the
ware. The surface may afterwards be rubbed over with the very finest
sandpaper, when entirely dry.

The finish of this work must not be a full glaze, but the “smear”
glaze, described in the last chapter. A full glaze would fill up the
lines, and so injure the appearance of the work. In order that the
black lines may be effective, the ground of the decoration should be
rather light in color. The best colors for the body of wares to be
decorated in this way are light cream color, or a mixture of cream
color and red clay, producing a light brick-red; or, if they can
be procured, any light colored clays which have been artificially
tinted in the body. A colored ground for this work can be procured by
having the piece of ware dipped in colored slips. The design is then
incised upon the surface, after it has become dry enough, in the same
manner as before. The lines are cut through to the body of the ware
beneath, showing a color contrasting with that upon the surface with
good effect. Work of this kind is also executed upon stoneware. That
of Miss Hannah Barlow will be remembered as an instance of incised
work, in black lines, upon a red or light brown body. Incised work
also appears upon the Lambeth stoneware. It is here used upon grey
stoneware, with raised dots in white, and colored with blue glaze.
Incised decorations can also be executed upon earthenware in this
way. White ware may be used, and the design drawn upon it in the
“green” state. The piece may then be finished with colored glaze,
which sinks into the depressions formed by the lines, and so gives
them a darker color than the rest of the surface. Carved work can
also be introduced with good effect as an accessory to incised work,
and a few words as to this kind of decoration will now be in place.


CARVING IN CLAY.

This work can be made very beautiful and effective by those familiar
with the use of carving tools. The tools used should be short-handled
carving tools, and the ware should be in the “green” state and as
for incised work, neither too wet nor too dry. Dry enough for clean
cutting with the tools, and yet not so dry as to be brittle. When in
just the right state, clay forms a fine substance for carving. As
it dries very rapidly, means should be used to keep it sufficiently
moist until the work is finished.

The outline can be drawn upon the clay with a sharp-pointed modeling
tool, and the carving can be executed with gouges, chisels, and
parting tools of the various shapes and sizes necessary. Veining can
be done with a pointed modeling tool, and dots can be readily incised
by pressure on the surface. Raised dots can be made with softer clay
which has been dipped up in a quill of the required size, which is
then pressed upon the surface at the place where the dot is desired.

Carved work can be finished by the use of sand paper, a camel’s
hair brush, and water, or a sponge; but these should not be used
very freely, as they will injure the sharpness and cleanness of the
cutting, which it is desirable to preserve. Carving looks best when
finished with a “smear” glaze.

Another variety of carved work can be produced upon a vase which has
been previously dipped in colored “slip.” The design is then cut
through the covering to the ground beneath, which should be of a
contrasting color.

Another method by which many varied and beautiful effects can be
produced is that of incising lines, and cutting or pressing designs
into the soft clay, which are then filled with various colored slips.
The lines or other designs should be deeply cut, moistened with water
and filled with the colored clays, which should be pressed into the
depressions and allowed to dry. When dry, the surface can be scraped
in a similar manner to that made use of in finishing incised work. It
should be noted that in this latter work the body of the clay should
be in a softer state than would be necessary for other carved or
incised work.

Carving in clay, as well as modeling and incising can be glazed with
the colored majolica glazes with excellent effect.



CHAPTER VII.

PAINTING UPON THE BISCUIT.


After the ware has been fired once and is in what is called the
“biscuit,” it can be decorated by the use of underglaze colors, in
the form of thin washes resembling water-color painting. Ware used
for this purpose should be made of white, or very light cream-colored
clay, as the colors, being used in transparent washes, would be
dimmed, and would have their tints sullied by use upon a ground of
dark color.

On white ware those colors should be used which will best stand the
heat necessary in the firing and glazing of this ware. For this
reason painting executed on white is usually in monochrome, and
only the strongest colors are used, such as blue, black, or brown.
The best effect is produced by the use of blue. This style of work
is familiar from the numerous pieces of Japanese ware, of porcelain
or white earthen-ware, painted in blue, which are brought to this
country.

The method of painting is simple and not likely to prove difficult or
uncertain as to its results in the hands of one familiar with the use
of water colors. The color generally used is dark blue, and there are
several different blues which furnish very fine tints. Among these
might be mentioned Emery’s cobalt blue, which is excellent and does
very well upon the white ware manufactured here. Phillips’ mazarine
blue and Harrison’s Persian blue are also very rich, deep colors, the
latter having a purplish tint. One of the best blues, as reliable and
pleasing in color as any, has been prepared by Mr. Joseph Bailey, of
the Hamilton Road Pottery.

The color must be rubbed down until perfectly smooth, and should
be mixed with water and enough gum arabic to keep it from rubbing
off in the necessary handling before firing. The design having
been sketched upon the ware to be decorated, with a lead pencil,
the first washes may be put in with a light tint of the blue. These
should be laid on with a free hand and without retouching before
they have dried. The darker tints may then be laid in, and lastly
the deepest shadows. These should be painted thickly and sharply to
give the proper depth of color. If necessary they may be painted over
a second time; care should be taken, however, not to have an excess
of paint in any part, as that would prevent the glaze from adhering
to the ware. The lines should be particularly clear and sharp, as
they generally spread more or less in the glazing, and if they are
not well defined and the shadows are not dark enough, the effect
will be blurred and indistinct. In this kind of work clearness and
distinctness are to be desired. If the painting is carefully executed
and the various degrees of light and shade are well preserved,
something of the effect of a painting in water colors will be
produced. Monochromes in brown and black are done in the same way,
only that in the case of the latter color it is better to mix a very
little blue with it, as that will make it stand the fire better.
Before glazing, the ware should be fired once to “harden on” the
colors. If the color should run in the glazing, the painting may be
repaired by the use of gilding over the glaze, by which the blurred
outlines may be concealed. When, from the perfection of the firing,
this is unnecessary, work of this kind, and especially that in blue,
may be very much enhanced by a judicious use of gilding.


PAINTING IN THE LAMBETH OR BENNETT STYLE.

This is done upon a very light, cream-colored ware. The method of
painting is similar to that described above, with the exception that
all colors can be used. In using the weaker colors, and in mixtures,
the same rules that have been given before must be observed. Colors
which do not stand the fire very well, such as yellow and rose
color, must be laid on thickly, while in mixtures, as well as when
used alone, the stronger colors should be used sparingly. In the
Lambeth or Bennett style of painting upon faience, the designs are
either wholly or partly conventional. The grounds are either left the
natural color of the ware or painted. The designs usually of flowers
are in natural colors very slightly shaded and surrounded by a dark
outline.

The design having been drawn upon the surface with a lead pencil,
the ground, if it is to be colored, may be laid on with some color,
or mixture of colors, which will harmonize with the decoration. As
it is impossible to paint it smoothly with a brush, or to do it by
any of the methods in use for over-glaze painting, the ground must
be “dabbled” on, either with a small blending brush, or better, a
sponge, which has been cut to the proper shape and size, and which
may be fastened in a quill and used as a brush. This is dipped in the
color which has been mixed upon the palette, and with it the color
is applied to the surface of the vase, producing a mottled ground,
which may be shaded from light to dark, by the application of more
or less color, as desired, and also may be varied by the introduction
of other colors which will harmonize with each other, and with the
decoration. The design may then be painted in flat washes, which
should be laid on freely, with the shadows boldly defined. This done,
a line, either of black or dark olive green, made from dark brown
and a little green, may be painted around the design, outlining and
relieving it against the ground.

The painting finished, the piece should then be fired to fix the
colors. If necessary, it can be touched up in any places which are
thought to need deeper tints after this firing, and before the final
process of glazing. It must be remembered, however, that the effect
of the glazing will be to deepen the colors, and, unless the result
of this process has been learned from experience, the tendency will
rather be to get them too dark than too light. The most important
thing is, to keep the relative value of the lights and shadows. If
this is done, the effect will not be bad, even if the colors should
fade a little in firing.

Another very important item in under-glaze painting, which has been
mentioned before, is, that the colors must be in proper condition for
use, and to that end, must be carefully rubbed down with a muller or
palette knife. Inattention to this detail has caused much work of
rude and rough appearance to be produced, which might otherwise have
been fairly good.

In the Lambeth and Bennett ware the charming effect of color will
generally be found to have been produced by a system of burning which
would scarcely be considered legitimate, according to the strict
rules of the potter’s art. The ware is not fired in the biscuit as
hard as such ware is usually fired, and the glaze applied is softer
than the body of the ware demands. This soft glaze is used to save
the colors, and not being suited to the body of the ware will,
generally, be found to be badly crazed. In this case, however, lovers
of beautiful and harmonious colors, in the decoration of pottery,
will think that the ends justifies the means, and as the articles
are wholly adapted for ornamental purposes, this defect of glaze
detracts but little from their value.

Some work of a similar character has recently been done in this city,
however, in which the ware has been fired and glazed in such a manner
as to make it perfectly durable, and, at the same time, great beauty
of coloring has been retained. This result is not only important from
the fact that it offers opportunity for the production of ornamental
wares, but, also, from the consideration that the perfection of the
firing and glazing of the ware renders it valuable for articles of
use. Nothing could be prettier than sets of tableware made of this
cream-tinted clay, decorated in colored, conventional designs. This
would, we think, be the perfection of ware for ordinary use, and
would form, with the combination of the delicately tinted body and
the harmonious colors of the underglaze decoration, a service both
pleasing to the eye and very durable.

It is not the province of a work on under-glaze painting to
enter into the subject of over-glaze decoration, yet as they are
frequently combined, mention may be made of some of the varieties
of decoration in which the two processes are used. The most common
form of the union of the two methods is that in which gilding is
used as an adjunct to under-glaze decoration. Gold is always applied
over the glaze, as it would be utterly destroyed by the action of
the heat necessary in the firing of any hard glaze. That prepared
by decorators by dissolving gold in aqua regia may be used, or the
“bright” gold, which is obtained in a liquid state. The former is
the most durable, and when fired can be burnished or left with a
dead finish, which in many cases has the most pleasing effect. The
“bright” gold, as its name indicates, becomes bright in the firing
and the burnishing is thus rendered unnecessary. On a “smear” glaze
the “bright” gold produces a beautiful dead gold effect, owing to the
dead surface of the ware to which it is applied. In Japanese wares,
dark blue, under-glaze, often appears in conjunction with gold, and
also with red, green, or other colors which have been put on over the
glaze.

One beautiful result of the combination of over and under-glaze
painting is seen in the ware painted by Lemonnier. In this the ground
is generally painted under the glaze in a manner similar to that
described in this chapter for the production of Lambeth faience.
The design is then painted with over-glaze “relief” colors, and the
high lights laid in heavily, the whole producing an effect which
combines the delicacy of the over-glaze colors with the depth of the
under-glaze.

We have tried to indicate, in the preceding chapters, the principal
methods employed in the decoration of pottery under the glaze. These
various methods are combined with each other and with over-glaze
work in so many ways that it is difficult for any but an expert to
distinguish in a given piece of ware the many processes which may
have combined to produce the result. This renders the subject more
difficult to treat comprehensively, and these various ramifications
of the art of under-glaze painting can here be but indicated. It
is hoped, however, that the suggestions given may be sufficient to
afford the student of ceramic decoration an idea of the various forms
and of the possibilities of the art.

[Illustration: Finis]



  Transcriber’s Notes

  pg 44 Changed: glaze sufficiently soft to perserve
             to: glaze sufficiently soft to preserve

  pg 49 Changed: may be added a drop of salycilic acid
             to: may be added a drop of salicylic acid

  pg 57 Changed: in colored slips, and the thicknesss
             to: in colored slips, and the thickness

  pg 92 Changed: delicately tinted body and the harmonions
             to: delicately tinted body and the harmonious

  Table of Contents was created by the transcriber.



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