These technical secrets, known centuries ago in Persia and the far East, have been coveted by ceramists down to the present day. They have been and are the most jealously guarded possessions of artists and factories, and history records many instances of the extreme precautions adopted to prevent their spread. The Japanese, for example, although indebted to China and Corea for the foundation of the knowledge upon which the magnificent structure of their subsequent art was built, guard with the utmost care the borrowed secrets in their{40} possession. In a native work on porcelain it is said: “The painting and decoration of vases is a secret that it is not permitted to reveal.” Similar instances present themselves on every hand. The production of any unusually beautiful color, although really only one-half of the difficulty with which the ceramic artist has to contend, is universally regarded as a triumph. Such were the efforts upon which the potters of China expended their skill, and upon which the emperors of the Flowery Kingdom bestowed rewards. There are dynastic colors, but no dynastic style of ornamentation with design. The ability to apply color to an artistic creation was a secondary matter, and went without recognition. The position of the artist and the workman were thus in a measure inverted, if we insist that the production of color is mechanical, and its application artistic. If the decoration be examined, its execution in detail will be found to be almost perfect—birds of brilliant plumage, flowers of richest hue, men and women draped in Oriental splendor (Fig. 15). In every case the colors used are those which produce the subtlest harmony. They gleam through the glaze like gems, or lie upon its surface like drops of pearl, ruby, or emerald. The drawing is precise and minute. A cylindrical Japanese vase, in Mr. J. T. Sutton’s collection, is decorated with a flock of cranes. They cover the upper part of its surface, flying, turning, diving, in every conceivable attitude—a perfect whirlwind of birds. The decorator has, with astonishing skill, seized upon the varied attitudes most suggestive of motion, and has produced what might be called “a study of cranes,” as far beyond the apprehension of a European artist as the minutiæ are beyond his skill. Elsewhere we may see a masterpiece of manual dexterity. It is reticulated, or articulated; or has its paste perforated, and then covered with glaze; or it may be a grotesque expression of Oriental humor. Others are decorated with designs in color, and their aspects have no monotony.{41} Should one side weary, the vase may be partially turned, and an entirely new effect is secured. In it, as in that described above, there is no repetition.
In Oriental work, as a whole, we therefore find skill in manipulation, similitude in drawing, and beauty in color; and the greatest of these is color. We have seen how it was regarded by the Chinese themselves, and our collectors follow their lead. They value one piece for the rarity of its prevailing green, another for the depth of its turquoise, a third for the clearness of its blue and the transparency of its white, a fourth for the harmony of its many tints, a fifth for the skill displayed in its quaint form and decoration.
We thus reach an interesting point where some instruction may be gained. On the one hand, are the Greeks pursuing beauty of form with assiduity and marked success; on the other, are the Orientals occupying themselves with mechanical skill and the beauty resulting from color. Both were right so far as they went. Men will admire Greek pottery so long as they have any sense of elegant proportion; they will admire Oriental pottery so long as they find any beauty in the changing colors of a kaleidoscope or in a gem. The aims and ideals of the two peoples were different, and the world has not yet seen the combination of a gracefulness of form equal to the Greek with the coloring of the Orient.
Fig. 16.—Nankin Porcelain. Brown bands; base, white; body, pale green; neck, light brown. Decoration chiefly pink, green, and blue; neck and body crackled. (Sutton Coll.)
In other directions, especially in Europe, it is more difficult to unravel the lines of art, or to specify, without numberless exceptions and modifications, the distinctive aims of artists or schools. The example of the Orientals has led some manufacturers to choose the production of color as their great aim. They have no intelligent comprehension of its higher uses, as these might be studied in Chinese decoration. They form an exaggerated estimate of Oriental processes, and {42}seek to equal the wonderful coloring of the faience of Persia or Rhodes. If they fail, as is generally the case, they are in no way deterred from using their inferior colors as the Orientals used the riches of their palette. Instead of turning toward a new object within the compass of their lower skill, they appeal to the eye with works which, by suggesting comparison with the models that inspired them, are at once condemned. If a vase of Nankin porcelain should be placed side by side with a Delft copy, the force of this will at once be seen.
It is comparatively easy to assign a place to Palissy. His career deserves study as an illustration of the movement of art between the conventional and the natural. As we look back upon his works, we find that truth to nature, in both form and color, was the guiding motive in the production of his most remarkable pieces. We owe the romance of his life to his earnestness in attempting to solve the mysteries of enamel. “I thought,” he says, “that if I could discover the invention of making enamel, I should be able to make vessels of earth, and other things of beautiful arrangements, because Heaven had given me to understand something of painting; and thenceforth, without considering that I had no knowledge of argillaceous earth, I set about seeking enamel like a man who gropes in the dark.” The story of his trials, his failures and successes, his poverty, honors and persecutions, compose the great romance in the history of ceramics. What he attained was, first, a white enamel; then, jasper glaze of warm tints of blue, brown, and white; lastly, his Rustiques figulines (Fig. 17). The last was his crowning effort. We regard him both as the leading representative of French art in the sixteenth century, and as a great originator. He had made, after long struggle and endeavor, a great discovery in enamelling; but what we admire more than that is the ideal he had formed. He developed skill, and aimed at both beauty and likeness. Palissy was great because, having chosen a certain line of art, he adopted the only ideal by which he could possibly reach perfection, viz., absolute truth to nature, alike in form and color. He neither spared himself nor overlooked any detail. His moulds were formed from living specimens. We recognize every ornament—shells of the district round Paris, reptiles and plants from the same places, and fish from the Seine. He did not dare to improve or conventionalize. He preferred nature as he found her; and his wisdom was genius. What we wish chiefly to note is, that here was an artist{43} who used the beauties of enamel for the reproduction of the natural. He not only moulded the clay into the forms of living things, but reproduced the colors of his models. No better examples can be given of Similitude. It hardly seems possible that his was a branch of the same art that we have seen in the East and in Greece. The fact of its being so merely shows the wide scope of ceramic art, and the infinity of the forms it may assume.
Fig. 17.—Palissy Dish. (Soltykoff Coll.)
Having chosen representatives of three different components of what we have assumed to be the highest form of art, we may now glance at the end in view, and see to what extent the lower forms may be worthily followed. Let us suppose that a piece of pottery or porcelain has been painted, and that the action of the fire has made the coloring perennial, so that we find on it a portrait or a landscape everlasting as the ware itself. Let us suppose, further, that the tints are natural, that, in short, the portrait is all that we now understand by the word, and that in the landscape nature is displayed as on canvas—then we should have a specimen of the perfect union of the potter’s and painter’s art.
The lessening obstructions in the way of such a consummation may be referred to in brief. The colors are mineral, and change by submission to fire, different temperatures producing different tints,{44} even when the same pigment is used. The painter, therefore, in applying the colors, must take into account the change to be effected by the fire in endeavoring to produce a certain result. He has not merely, it will be observed, to lay on given colors, and have them made perpetual by glazing and firing. He must estimate and make allowance for the transformations effected in the process. We are now in a position to realize the difficulty attending the exercise of the combined skill of potter and painter. As a consequence, although many great painters have turned their genius to the decoration of earthen-ware, others have been deterred from doing so by the very facts here mentioned. They are unwilling to submit their work to processes unattended with certainty, and to have their artistic individuality obliterated by the fire. It is clear, therefore, that if by any means doubt can be changed to certainty, and the finish characteristic of the individual artist be preserved, artists of every grade will gladly avail themselves of the opportunity to place their works above the reach of the defacing fingers of Time. The ceramic art would be revolutionized. Artists, being at present less able to follow nature, make a virtue of necessity, and lose themselves among fantasies of tint and form. We find elaborately decorated pieces, the great virtue of the floral ornamentation of which is, that it is—not true, but—new. A new leaf or a novelty in flowers is a valuable discovery; and the répertoire of the potter is filled with designs in which nature has no part. If nature be brought within the artist’s reach, it will be followed more closely; and the result might be the realization of Ruskin’s idea—the rendition of absolute similitude in outline, color, and perspective.
The next question arising is, in view of the restraints upon artists, what styles of decoration are the best? The subject is worth considering at length. There may be a beauty of a certain kind in the ware itself. As a rule, porcelain should never be overloaded with gold or any kind of decoration or color less beautiful than its own enamel. It demands lightness of ornamentation and gracefulness of design, rather than brilliancy of decoration. We can, when these canons are observed, find something to admire in capricious floral designs, even although they may not be floral to the naturalist. The best rule is to adapt the decoration to the object upon which it is{45} laid. It would be a violation of good taste to demand pictures upon plates, or that a soup-tureen should resemble a sarcophagus. If an object be for use, let its usefulness be the primary consideration; if for ornament, let its beauty be its first; if it be meant to combine them, let the ornamentation be that best suited to the useful purpose.
When we come to consider color alone, a distinction must again be drawn between articles for different purposes. Ornamentation may address either the eye alone or the sensibilities through the eye. Restricting ourselves to the former, the article will be the most ornamental which, apart from shape, seems most brilliant, and reflects the most light. To illustrate this, we might reproduce an object in different materials—diamond, ruby, topaz, gold, iron, lead, sand, and plaster. Show it, in all these materials, to a savage, an ignoramus, an artist, a woman, and each will select the copy in precious stone as the most agreeable to the eye. The plaster would be the least likely to attract, and the person choosing it would be at once put down as devoid of taste. Suppose, now, that a vase is presented to us duplicated in different materials, we should find the turquoise of Japan or the red of China more pleasing to the eye than stanniferous enamel. It would, again, be like choosing between ruby and plaster. In this way a rule could be drawn up capable of universal application, one which would surmount all the advancing and receding waves of changing fashion.
In the shape which an object intended for ornament should assume, or in the style of its decoration, there is, as we have seen, no absolute rule. Individual taste is paramount, since ornaments are intended mainly to administer to the pleasure of the possessor, but one rule may be considered universal in regard to the decoration. If the object be a vase intended to brighten a house, then its ornamentation should never be of such an order that its greatest and best effect is perceived when it stands alone. What ought to be kept in view, is the extent to which it will increase the attractiveness of the room in which it stands. It is a very curious fact that the most perfect decoration demands isolation for the appreciation of its full effect, and that decoration of comparative mediocrity will frequently add more to an apartment. We are thus led to observe that decoration is not an end, but a way, a means to the beautifying of a home.{46} Every such object in a house should be a note, and from combination of all the notes comes harmony. Were each a tune complete, however perfect, the result would be a jarring discord. For that reason, a vase of one perfectly simple color may harmonize with its surroundings as well as, or even better than, another showing a masterpiece of painting. Such a color must, however, be as near perfection as possible, like that of a precious stone. A vase of turquoise-blue may produce in a room the effect of diamonds in the ears of a woman. Taste is not likely to lead her to carry pictures in her ears, nor to exclude all but picture-painted porcelain from her rooms.
Having thus seen how ceramic productions illustrate the art ideas of all nations, having touched upon the influence of pottery upon art in general, and having glanced at its present aims and possible accomplishments, it will not be forgotten, after what has just been said, that the combination of the useful and the beautiful is the great charm of the ceramic art, making between them a new beauty which finds its best place in the household. Let us look at the usual appurtenances of the table. They both reflect taste and form it. A wide range is before us from which to choose—from the vulgarity of overloaded glaring colors and gilt, to the most exquisite simplicity of design and perfection of workmanship. Every house-keeper ought to visit an extensive collection, and, by comparing and contrasting one style with another, learn in what the true beauty of ceramic decoration consists. The painting and moulding of pottery and porcelain are quite as important as oil-painting and sculpture. As we look at the pictures and statues in a gallery, we read the stories they tell, feel the sentiment they express, study the grace they embody, or linger lovingly over the evidences they present of artistic skill. A plate may appear{47} an humble thing to which to turn from them. But let us consider the intimate relations into which we are brought with its unobtrusive beauty. It is the daily contact that lends so comparatively lowly a matter its real importance, and daily contact with delicately painted and gracefully moulded cups, platters, and dishes cannot be without its influence upon taste. Or suppose the ceramic treasure be an earthen-ware jar. It presents us with green, its depth suggestive of a forest glade, shading off into blue like that of the sky. As we turn it slowly round, a leaf appears attached to a tiny stem, and still farther lies a flower, colored with the very hue of nature, and suggesting the perfume of a garden in summer. Art such as that is never out of place, and never thrown away. Or let our attention rest upon more purely ornamental representatives of the art. There are vases which, while offering for our admiration a beauty which is eternal, are yet invested with a chameleon-like power of change. They never allow monotony to break their charm. It may consist of a mere color. Take the old turquoise-blue of China. The eye can scarcely catch the fleeting shades, to determine whether the vase is blue or green. While daylight lasts, the blue is dominant, but when the lamps are lit in the evening, the blue gives place to a green of greatly increased brilliancy. The same thing may be observed in many flower-painted vases. They may be examined once without revealing a tithe of their beauty. The sky is overcast and the outside world gloomy, and the flowers, as sympathetic as though growing in the garden, look sombre and drooping. But let a ray of sunshine fall across the vase, and mark how the flowers are glorified. Their hues change and brighten, and, as if endowed with life, they smile, and lift up their heads in the face of the sun.{48}
BOOK I.—NOMENCLATURE AND METHODS.
CHAPTER I.
TECHNOLOGY.
Confusion in Use of Terms.—Porcelain as an Instance.—Derivation of Ceramic.—Pottery.—Faience.—Majolica.—Mezza-Majolica.—Composition of Porcelain.—Origin of Word.—Where first made.—When introduced into Europe.—Hard and Soft Paste.—Soft Porcelain of Venice, Florence, England, France.—Hard Porcelain invented at Meissen by Böttcher.—Vienna.—Discovery of Kaolin in France.—Biscuit.
IT will be necessary as we proceed to make use of certain terms, the meaning of which should be defined with as much exactness as possible. It may be premised that considerable confusion exists in the nomenclature of the art. This has arisen partly from the want of precision in the language employed by writers, and partly from diversity of usage. As an illustration, the word “porcelain” may be adduced. The material to which the Egyptians applied a glaze, and which was very largely used in making ornaments and small images, has been called, and is constantly spoken of, as Egyptian porcelain (Fig. 20). In reality the substance is not porcelain, having neither the transparency nor the hardness of that ware, but a compound between porcelain and earthen-ware. The word was also used by the Italians in the sixteenth century, to designate their finer qualities of majolica. An equally incongruous application of it is made in the case of Lambeth faience, which is described by the manufacturers as a “kind of porcelain.” Such words as faience, hard and{49} soft porcelain, majolica, stone-ware, etc., are in continual use by writers upon ceramic art, and a few of the more important will now be defined.
Allusion has already been made to the derivation of the word “ceramic.” Viewing the subject more prosaically, the name κεραμος was applied by the Greeks to pottery in general, and also to a large jar; and several derivatives were used for the designation of different vessels. The potter himself was called κεραμευς, and the pot-market κεραμεικος. Although the matter has been differently viewed, it appears probable that the root of all the above words is κερας, a horn. The horn was used at a very early period as a drinking-cup, and a more decided air of probability is thus given to the above assumption, since Bacchus was the reputed parent of [Greek: keramos κεραμος], or Ceramus. However philologists may ultimately settle this matter, the word “ceramic” is now employed to designate the potter’s art and its productions.
The word “pottery” is variously used. Its root is the Latin potum, a drinking-vessel. It is applied, according to general English usage, to all wares distinguished by their opacity from translucent porcelain. The French word poterie, on the other hand, is applied to all vessels, including those made of porcelain. The latter fact has led to a slight confusion in the use of the English word. One writer makes the assertion in one place, that the words “earthen-ware” and “pottery” have limited and distinctive meanings, the former applying only to vessels of the coarser qualities, the latter to the finest products of the fictile art, “including even porcelain.” In another place, he draws a distinction between pottery and porcelain, and in the latter course he is followed by the present writer.
Faience, fayence, or fayance, is a French word applied to every kind of glazed earthen-ware. According to the earlier French usage, the term included porcelain, but more lately it has been applied only to pottery.
The word “majolica,” as now employed, has almost the same meaning as faience. A more limited signification is attached to it by some. The writer of the article on pottery in “Appleton’s Cyclopædia” says it is used “to signify all faience of Italian manufacture. Lately the word has been used as almost, if not quite, synonymous with faience.” A more recent writer has said, “In its now common acceptation, the word is applied to all kinds of decorated pottery made{50} in Italy, or made in colors and styles imitating the old Italian work. But when you read a book on pottery written during the present century by an expert, you will do well to remember that the word in that book means exclusively Italian decorated pottery of the fifteenth, sixteenth, seventeenth, and eighteenth centuries, in the old Italian styles. It does not include Italian vases made in imitation of German, French, Dutch, or English wares.”
The changing meaning of this word is a good illustration of the careless use of the terms employed in treating of ceramic art. Originally, majolica, or maiolica, had a meaning different from any of those given above. The name is derived from Majorca, the largest of the Balearic Islands, between which and Italy intercourse is known to have taken place in the twelfth century; and two hundred years later, the commercial transactions of Majorca were of a very extensive kind. The evidence in favor of the above derivation of the word is conclusive. Scaliger says distinctly that the Italian pottery derived its name of majolica from Majorca, where the pottery was most excellent. Ferrari believes that “the use of majolica, as well as the name, came from Majorca, which the ancient writers called Majolica.” The “Dictionary della Crusca” adds weight to these authorities. Such being the case, it seems probable that the Italians derived part of their knowledge of making majolica from the place which gives it its name. Even admitting that the Saracens who settled in Sicily, and the Moors expelled from Spain who settled in Italy, initiated the Italians in the art, nothing is thereby detracted from the importance of Majorca. The fact is left unaffected that the intercourse with the Balearic group enabled the Italians to find a name for the ware they admired so much. On trying to imitate it, the ware called “mezza-majolica” was produced. The red clay was first thinly coated with white earth, upon which the colors were laid. After a partial firing, lead glaze was applied, and lustre pigments gave the ware the iridescence characteristic of real majolica. It was after this that tin enamel was used in place of a white slip; and the lustre pigments being applied as before, fine majolica was produced. It will thus be seen that the words “mezza-majolica” and “majolica” were originally applied only to wares showing the reflet métallique, or lustre. This limited use of the word was observed down to the middle of the sixteenth century. Piccolpasso,{51} writing in 1548, in no case applies the name to the painted and glazed wares of his own production. All the glazed earthen-ware of Italy was thereafter called majolica; and the application of the word has been growing wider ever since. Mr. Fortnum says, “We think, with M. Jacquemart, M. Darcel, Mr. J. C. Robinson, and others, that the word ‘maiolica’ should be again restricted to lustred wares.” Any such attempt must necessarily end in failure. The popular employment of a word is not to be controlled by its scientific application. The tendency is in the opposite direction—toward the establishment of a universal usage by which faience and majolica will become convertible terms.
The different kinds of ware, such as Lucca della Robbia, Palissy, Doulton, and Limoges, will be found described under the countries to which they belong.
Porcelain is composed of two ingredients, one of which—kaolin—is infusible, and the other—petuntse—vitrifies, and envelops the kaolin. It is translucid, and therein differs from pottery, which is opaque. As to the origin of the word, we have already seen that it was, in its Italian form, applied to majolica in the sixteenth century; and the word “pourcelaine” occurs two centuries earlier. It was used to designate Oriental china in the fifteenth century. Mr. J. F. Davis, in his work on the Chinese (1840), quotes Marsden to the effect that the word “porcelain,” or porcellana, was applied by Europeans to the ware of China, from the resemblance of its fine polished surface to that of the univalve-shell so named; while the shell itself derived its appellation from the curved or gibbous shape of its upper surface, which was thought to resemble the raised back of a porcella, or little hog. When porcelain was first invented in China is not exactly known. The combination was discovered in the province of Honan about eighteen hundred years ago; but the date cannot be more specifically fixed. From China it was introduced into Persia, Egypt, and Barbary, at a very early period, and was thence imported into Europe, where, however, it was not generally known until 1518. The first specimens of Oriental porcelain known to have reached England were given by Philip of Austria to Sir Thomas Trenchard, of Wolverton, in 1506.
To continue its history in Europe, it is necessary to observe that there are two kinds of porcelain—the natural, or pate dure, and the{52} artificial, or pate tendre. The latter cannot stand so high a temperature as the former, and can be scratched with a knife, which the hard porcelain resists. The soft-paste was the first to be discovered in Europe. Chemists, struck with the beauty of the Chinese porcelain, and impelled by a desire to imitate, began to experiment in the sixteenth century; and the first success, of which substantial evidences now exist, was gained at Florence in 1580. It is said that a Venetian potter made porcelain sixty or seventy years earlier; but no specimen known to be his is now in existence. After that of Florence, the next discovery was made by Dr. Dwight, of Fulham, England, in 1671; and in 1695 the secret was penetrated by M. Chicanneau, at St. Cloud, France. By that time the Florentine porcelain and process had been forgotten, and the English and French ceramists pursued perfectly independent investigations.
The problem of making a hard-paste porcelain resembling that of the Orient still remained unsolved. No chemistry could avail the experimenters so long as the materials were wanting. To the accidental discovery of a bed of kaolin, Europe owed its first hard porcelain. This important event took place about the year 1709, and the circumstances leading to it are full of interest.
John Frederic Böttger, or Böttcher, was a chemist’s assistant in Berlin, and having fallen under suspicion as an alchemist, he took refuge in Saxony, which was then under the electorate of Augustus II. The elector, having questioned him as to his researches in the forbidden science, placed him in the laboratory of a chemist who was in search of the philosopher’s stone. While working to that end, Böttcher surprised himself by producing something akin to Chinese porcelain. The course of his experiments was turned at once from the channel in which it had run. The king gave him every facility for continuing his experiments and working out his secret. He was first established at Meissen, then at Königstein, and last at Dresden. The first results were comparatively rude; then came a reddish stone-ware, and afterward a dull white porcelain. How long his experiments might have been continued, or what might have been their ultimate result, cannot be estimated, had not an accidental discovery brought the object at which he was aiming suddenly within his reach. John Schnorr, a wealthy iron-founder, riding one day in the vicinity{53} of Aue, near Schneeberg, Saxony, noticed that his horse lifted his feet with difficulty. On examination he found that the clay was very white and peculiarly adhesive. Schnorr, although rich, would gladly be richer, and avarice made him ingenious. Why not use this white earth in the making of hair-powder? was the question which occurred to him. The commodity was dear, and clay was a cheap substitute. He took a quantity with him, made the new hair-powder, and was successful in his venture. In due course, the new powder reached Böttcher, and he, in turn, found an original use for the white earth. Inquiring into the nature of the powder, he found it was earthy, and at once tried it in his laboratory. The powder was kaolin, and hard porcelain was discovered. A manufactory was established at Meissen, of which Böttcher was director until his death, in 1719.
In 1720, the manufacture was begun at Vienna, whither the secret was carried by an escaped foreman from Böttcher’s works at Meissen.
It is very curious to note that the first manufacture of hard porcelain in France was due to a chance discovery almost identical with that made in Germany. Kaolin had been found at Alençon, but the porcelain made from it was not pure in color. In 1765, the wife of a surgeon found near St. Yrieix a peculiarly soft earth of great whiteness. Being poor, Madame Darnet was also economical. Unlike Schnorr, her thoughts turned in the direction rather of keeping down household expenses than of adding to her income. The earth had a soft, oily touch, and the good lady thought that it might answer all the purposes of soap. Her husband sent a sample to a chemist, and it was soon afterward decided to be kaolin. The manufacture of hard porcelain was begun at Sèvres in 1769, the quarries of St. Yrieix supplying both the kaolin and petuntse. As illustrating the ingratitude of the world, it may be mentioned that the humble instrument by whose aid France reached its lofty eminence in the manufacture of porcelain was, for about sixty years, left unrewarded. In 1825, Madame Darnet, spending her old age in poverty, received a pension from Louis XVIII.
Biscuit is the technical term applied to both pottery and porcelain before they are enamelled or glazed. In this condition, porcelain is of a dead white, and is not very well suited to receive decoration in colors which require a glaze to bring out their full beauty.{54}
CHAPTER II.
CLASSIFICATION.
Tabulated View.—Brongniart’s Division: Its Objections.—Classification adopted.—Leading Features and Advantages.—Distinctions between Different Bodies and Different Glazes.
IN order to avoid repetitions and explanations, and for the sake of lucidity, tabulated views of the different branches of ceramics are here presented. The first is least detailed, but gives the salient points of a systematic arrangement.
| POTTERY | Soft | Unglazed | Common brick. Earthen-ware. |
| Lustrous | Greek pottery. | ||
| Glazed | Some ancient and most modern faience. | ||
| Enamelled | Robbia ware. | ||
| Hard | Stone-ware. | ||
| Fire-brick. | |||
| PORCELAIN | Soft | Naturally soft | English porcelain. |
| Artificially soft | French porcelain, pate tendre, such as old Sèvres. | ||
| Hard | China. | ||
| Dresden. | |||
| Sèvres. | |||
The following is more full, and is to be ascribed to M. Brongniart:
| FIRST CLASS, SOFT-PASTE. |
| 1st Order. Baked clay without glaze. |
| 2d Order. Lustred wares with silico-alkaline glaze. |
| 3d Order. Glazed pottery with plumbiferous glaze. |
| 4th Order. Enamelled pottery, in the enamel of which tin is used. |
| SECOND CLASS, HARD-PASTE (OPAQUE). |
| 5th Order. Fine faience, uncolored paste with plumbiferous glaze. |
| 6th Order. Stone-ware without glaze, or with salt or plumbiferous glaze. |
| THIRD CLASS, HARD-PASTE (TRANSLUCENT). |
| 7th Order. Hard porcelain, paste and glaze both felspathic. |
| 8th Order. English natural soft-paste porcelain—paste, argillaceous kaolin, pegmatite, phosphate of lime, etc.; glaze, boracic. |
| 9th Order. French artificial soft-paste porcelain—paste, a frit, marly alkaline; glaze, alkaline containing lead, alkali, and silica. |
If these tables be studied carefully, it will be found that in arranging the nine orders, a gradual ascent is made from the humblest ware—baked clay left unglazed—to the finest of artificial compounds. Its only objection—and it is one very likely to confuse an inexperienced student of the art—is, that, under the head of hard-paste pottery, are classed the soft-paste porcelains of England and France. The question is, also, very likely to suggest itself, why the distinction should be drawn between the soft-pastes of England and France, and the one called natural, the other artificial. The reason is that the paste of England is naturally soft, while that of France is made soft by the chemical action of certain of its ingredients. The classification has, on the other hand, the advantage of being in general use. Terms are employed in its construction which have a peculiar but well understood significance; and even in its errors there is a modicum of truth. Thus, although the artificial porcelain of France is invariably called pate tendre, or soft porcelain, it is not improperly classed under translucent hard-pastes. The error is in the distinctive name rather than in the classification. There is, in reality, very little difference in hardness between the hard-paste and the soft-paste; and although the glaze of the latter is not so hard as the body, the appellation soft-paste has been adjudged a misnomer. The question then came to be whether it might not be better to retain the old terms, with an explanation of their technical meaning, than to supplant them with something new. The latter course has been adopted, upon the ground of obviating meaningless and misleading distinctions. Both simplicity and a clear understanding of one of the most important practical divisions of our subject point toward a revision of the old system of grouping. Pottery and porcelain differ in one essential respect, and their varieties can also be classed according to the leading features of their composition, manufacture, or appearance. These differences have been taken as the basis of the following classification, against which, at least, none of the objections to that of M. Brongniart can be brought. It has been prepared by a distinguished French artist of the present time, and is offered in the hope that it may be intelligible, although it is not claimed to be either perfectly exact or altogether complete.
All wares are divisible into two great classes, viz., transparent porcelain and opaque earthen-ware.{56}
- Porcelain may be natural or artificial
- I. Natural porcelain is made from kaolinic clay. It may have—
- 1. A pure felspathic glaze, such as porcelain of China, Japan, Limoges, Sèvres, Dresden, Berlin; or,
- 2. No glaze, such as the biscuit porcelain of China or France.
- II. Artificial porcelain may be made from alkaline clay, calcareous clay, or felspathic clay.
- 1. Alkaline clay may have an alkaline glaze, either colorless or colored, or may be biscuit.
- a. Alkaline glaze, colorless—Persia, China, St. Cloud, Limoges, Sèvres, Tournay.
- b. Alkaline glaze, colored—Persia, China, Limoges, Deck.
- c. Biscuit—Old Sèvres statuettes.
- 2. Calcareous clay has a colorless boracic glaze, as in the case of the English china of Minton, Copeland, and Worcester.
- 3. Felspathic clay is exemplified in the parian of Copeland, Minton, and Worcester.
- 1. Alkaline clay may have an alkaline glaze, either colorless or colored, or may be biscuit.
- I. Natural porcelain is made from kaolinic clay. It may have—
- Earthen-ware is of two kinds—that showing a non-vitrified fracture, and that showing a vitrified fracture.
- I. Earthen-ware with non-vitrified fracture may have either a transparent glaze or an opaque enamel.
- 1. Transparent glaze may be plumbiferous or alkaline, and in either case colorless or colored.
-
- a. Plumbiferous.
Glaze, colorless—Faience d’Oiron or Henri Deux ware, Wedgwood, Meakin, Creil, Montereau.
Glaze, colored—Palissy, Nuremberg, Minton’s majolica. - b. Alkaline.
Glaze, colorless—Persian faience, Chinese and Japanese faience; Deck, of Paris.
Glaze, colored—Haviland or Limoges faience.
- a. Plumbiferous.
- 2. Opaque enamel is stanniferous, and may be either colorless or colored.
Stanniferous, colorless—Della Robbia, Rouen, Moustiers, Delft, Nevers.
Stanniferous, colored—Colinot, Parville, Longwy.{57}
- II. Earthen-ware with vitrified fracture may be either glazed or in biscuit. Of the former, the Grès of Germany, Beauvais, and Doulton may be taken as examples.
- I. Earthen-ware with non-vitrified fracture may have either a transparent glaze or an opaque enamel.
For convenience of reference, the same classification may be given in tabulated form:
| CLASSIFICATION OF ALL KINDS OF WARE. | ||||
| Translucent Porcelain. |
Natural | Kaolinic paste | Glaze of felspath, pure | China, Japan, Dresden, Berlin, Sèvres, Limoges. |
| Biscuit | Biscuit porcelain of Limoges and China. | |||
| Artificial | Alkaline paste | Glaze alkaline, colorless | Persia, China, St. Cloud, Tournay Sèvres, Haviland. | |
| Glaze alkaline, colored | Persia, China, Deck, Haviland. | |||
| Biscuit | Old Sèvres statuettes. | |||
| Calcareous | Glaze boracic, color | English china, Minton, Worcester, Copeland. | ||
| Felspathic paste | Parian | Copeland, Worcester, Minton. | ||
| Opaque Earthen Body. Terres. |
Earthen body with a non-vitrified break |
Transparent glaze. | Plumbiferous glaze | Glaze, colorless | Faience Henri II., Wedgwood, Meakin, Creil, Montereau. |
| Glaze, colored | Palissy, Nuremberg, Minton’s majolica. | ||||
| Alkaline Glaze | Glaze, colorless | Faience of Persia, China, and Japan; Deck. | |||
| Glaze, colored | Limoges faience of Haviland, Bracquemond, and Chaplet. | ||||
| Opaque | Stanniferous enamel | Colorless | Delia Robbia, Rovigo, Fontana, Rouen, Moustiers, Nevers, Delft, Ulysses de Blois, St. Clement. | ||
| Colored | Colinot, Parville, Longwy. | ||||
|
Earthen body with a vitrified break |
Biscuit | Boccaro, Bizen. | |||
| Glaze | Grès from Germany. | ||||
Under the above arrangement, it will be observed that the distinction{58} between hard and soft porcelain and pottery is done away with. The first is divided into natural and artificial, the kaolinic paste being the only one coming under the former head, and the “soft-pastes” of both England and France coming under the latter. The subdivisions are made according to the glaze employed. The division of pottery into two classes, according to the nature of the body as revealed by fracture, is the most lucid and comprehensive. The subdivisions, as in the case of porcelain, are made according to the enamel or glaze applied to the ware. It is presumed that any one can distinguish between transparent and opaque wares, and thus tell porcelain from pottery, and similarly, tell whether the fracture of a broken specimen is vitrified or otherwise, and thus distinguish stone-ware, or grès, from ordinary earthen-ware.
In the matter of glazes, it requires a great deal of skill and long practice to tell one from another. All are transparent, with the exception of tin or stanniferous enamel. Felspathic glaze is that most readily recognized; but in the case of the others—the alkaline, plumbiferous, and boracic—they are very often only to be distinguished by their different effects upon the colors used in decoration.{59}
CHAPTER III.
COMPOSITION OF WARES AND GLAZES.
Hard and Soft Pottery and Porcelain.—Composition of Porcelain: Kaolin—Its Derivation and Ingredients—Petuntse—How prepared in China.—The European Process.—Differences between Chinese and European Porcelains.—Chemical Analysis.—English Porcelain and its Peculiarities: Its Average Composition.—How English Clay is prepared.—French Artificial Porcelain.—Parian.—Common Earthen-ware.: Table of Ingredients of different kinds.—General Table.—Glazes: Classes.—Brongniart’s Classification.—Difference between Enamel and Glaze.—Silicious Glaze.—History.—Use of Oxides.—Egyptian Processes.—Metallic Lustre.—Stanniferous Enamel: Its History.
THE division of pottery and porcelain into two great classes, hard and soft, is based upon the difference of their composition, their hardness of surface, and their power of resisting the action of fire. The simplest test is scratching with a knife or other instrument. Hard porcelain and pottery resist the metal, while the soft is marked. The former will also stand a temperature in the kiln at which the latter would crumble or fuse.
To understand the composition of porcelain, it is necessary to bear in mind that it is a compound of kaolin and petuntse, the former of which is infusible, and the latter fusible at a high temperature. The former constitutes the body of the piece, the latter gives it its translucency. The word “kaolin” is derived from Kaoling, the name of a mountain near King-teh-chin, one of the great centres of the manufacture in China. Kaolin is simply the result of the decomposition of granitic rock, and silica and alumina are its chief ingredients. Petuntse is pure felspar. The conditions in which these materials are found in China may be briefly stated. They are either in the form of stone or sand, from which the unsuitable parts are removed by the action of water. When they are thrown into the water, the fine particles which do not sink are collected and dried. The paste, before being used, is again put into water and strained through a sieve, so that only the finest is preserved, and used in making porcelain. The{60} materials are obtained from different parts of the country, and blended according to their respective qualities, as ascertained by the most systematic investigation and experiment. The European process is similar, the kaolin being first washed clear of all argillaceous impurity, and then mixed with felspar and silicious sand. Of the further similarity between the two, MM. Ebelman and Salvetat say:
1st. The kaolin and petuntse used in making paste for Chinese porcelain are chemically identical with the materials used in Europe. The Chinese kaolin is evidently disintegrated granite. Chemically, petuntse resembles the pegmatite of Limoges; mineralogically, it is to be classed with petrosilicious felspar.
2d. The mechanical preparation of the pastes of China and Europe is based upon similar methods.
3d. The Chinese paste is the more fusible of the two.
4th. The Chinese glaze is also the more fusible, on account of the addition of lime to the petuntse, which the French use pure.
It may be added that the Dresden, Sèvres, and Limoges porcelains are baked at a higher temperature, and are harder than the Chinese.
The basis of the natural pastes of Germany and France is 46.66 parts of silex, 40 of aluminous earth, and 13.33 alkaline earth, although the proportions vary, and the following may be nearer an average: Silex, 66; alumina, 30; potash, magnesia, and lime, 4. In the glaze the proportions are different, the silica largely preponderating: Silex, 73.4; alumina, 15.7; potash, lime, and magnesia, 10.9.
The following table is given by M. A. Salvetat as the result of analyses made at different times by himself and others:
| Pastes. | Silica. | Alumina. | Oxide of Iron. | Lime. | Magnesia. | Potash. | Soda. |
| China, 1st quality | 69.00 | 23.60 | 1.20 | 0.30 | 0.02 | 3.30 | 2.90 |
| China, 2d quality | 70.00 | 22.20 | 1.30 | 0.80 | traces | 3.60 | 2.70 |
| China, 3d quality | 73.80 | 19.30 | 2.00 | 0.60 | traces | 2.50 | 2.30 |
| China, 4th quality | 68.94 | 21.30 | 3.48 | 1.14 | traces | 3.42 | 1.78 |
| Meissen | 58.50 | 35.10 | 0.80 | 0.30 | traces | 5.00 | .... |
| Vienna | 59.60 | 34.20 | 0.80 | 1.70 | 1.40 | 2.00 | .... |
| Berlin | 64.30 | 29.00 | 0.60 | 0.30 | 0.45 | 3.65 | .... |
| Limoges | 70.20 | 24.00 | 0.70 | 0.70 | 0.10 | 4.30 | .... |
| Sèvres | 58.00 | 34.50 | .... | 4.50 | .... | 3.00 | .... |
| Sèvres (sculpture) | 64.10 | 30.24 | .... | 2.82 | traces | 2.80 | .... |
| Worcester | 82.00 | 9.10 | ..... | 1.30 | 7.40 | .... | .... |
| Paris | 71.20 | 22.00 | 0.80 | 0.80 | .... | 4.50 | .... |
The English artificial porcelain differs from the natural paste of China and the European continent chiefly in one particular. At first the compound used was white clay, white sand, and glass, the latter being employed to impart the necessary transparency. More recently bone came largely into use, and is now one of the distinctive ingredients of English paste. The phosphoric acid of that material was found to produce, in combination with the other materials, a clear, translucent body, of less strength than natural paste, but less liable to sink. The following may be taken as the mean composition: Bone, 47; kaolin, 34; felspar, 19. The kaolin is found in Cornwall, where a very large tract is formed chiefly of decomposed granite. The purest rock having been selected, it is placed on an inclined plane, upon which water can be turned. It is washed down into a trench, and thence into a catch-pit, and again into lower pits, in which successively the impure ingredients are retained, the water laden with the finer particles running into tanks, and there depositing its fine silt. The clay is partially dried, and cut into blocks, and in that shape reaches the potters. The manner in which the kaolin is prepared bears a very close resemblance to that adopted by the Chinese, as previously described. The glaze is composed of felspar, carbonate of lime, borax, and white-lead. Sometimes the kaolin is mixed with the bone and felspar in the proportions above specified, and sometimes the bone is made, in combination with silex and pearlash, into a frit.
The artificial or soft porcelain of France, exemplified in the old china of Sèvres, was produced by a very intricate and ingenious process. A frit was made of saltpetre, sea-salt, burnt alum, soda-ash, gypsum, and sand. This mixture, having been purified by partial vitrification, was ground, and mixed with chalk and marl. The glaze was as follows: Litharge, 38; sand, 27; calcined flint, 11; and the carbonates of soda and potash, 15 and 9 parts respectively.
The composition called parian, in which the potters of England and America have executed much beautiful work, varies considerably. Analysis of one specimen resulted thus: Silica, 58.57; alumina, 21; oxide of iron, 1; lime, 0.14; magnesia, 0.5; potash, 11.40; soda, 5.08.
The clay from which common earthen-ware is made is composed to a great extent of silica and alumina, with admixtures of iron, lime, and magnesia. An average combination is 60 parts silex, 30 alumina,{62} 7 iron, and 2 lime. These proportions vary very widely, certain substances appearing in one place and not in another. In some, carbon is found; in others, quartz, sand, marl, or chalk, as the case may be. The work of classification, except in a very extended form, is thus rendered somewhat difficult. Possibly the following series of tables will serve our purpose most intelligibly.
| Pottery. | Silica. | Alumina. | Oxide of Iron. | Lime. | Magnesia. | Water. | Carbon. |
| German | 63.90 | 12.76 | 10.24 | 1.04 | 0.52 | 9.98 | 1.02 |
| Scandinavian | 64.02 | 10.77 | 11.23 | 2.48 | 0.05 | 9.97 | 1.00 |
| Old Gallic | 62.22 | 18.36 | 5.71 | 1.17 | 0.47 | 10.56 | 0.78 |
| Peruvian | 67.04 | 10.83 | 10.17 | 3.24 | 0.28 | 7.07 | 1.00 |
| Etruscan | 64.02 | 12.49 | 8.53 | 3.00 | 1.83 | 8.13 | 2.00 |
In the following carbon does not appear, and the proportion of silica increases:
| Pottery. | Silica. | Alumina. | Oxide of Iron. | Lime. | Magnesia. | Water. |
| Roman | 64.00 | 17.77 | 10.23 | 4.86 | .... | 2.23 |
| Middle Ages | 72.55 | 20.27 | 2.54 | 1.04 | .... | 3.00 |
| Egypt | 81.00 | 13.50 | 1.00 | 3.00 | .... | 1.90 |
| Egypt | 92.00 | 4.00 | .... | 2.00 | 0.60 | 0.40 |
| Persian | 90.00 | 1.50 | 1.50 | 3.00 | 0.80 | 0.60 |
| Jerusalem | 87.16 | 5.50 | .... | 3.00 | 0.78 | .... |
| Arabian | 89.95 | 3.87 | .... | 2.00 | 0.51 | 3.00 |
The Egyptian, compounded as above, is that which has been commonly known as Egyptian porcelain. Many of the better known wares of Europe and the East have a common characteristic in the calcareous nature of their pastes. The silica decreases and the lime increases, while carbonic acid appears as a new ingredient.
| Pottery. | Silica. | Alumina. | Magnesia. | Oxide of Iron. | Carbonic Acid. | Lime. |
| Lucca della Robbia | 49.65 | 15.50 | 0.17 | 3.70 | 8.58 | 22.40 |
| Majorca | 48.00 | 17.50 | 1.17 | 3.75 | 9.46 | 20.12 |
| Spain (old) | 46.04 | 18.45 | 0.87 | 3.04 | 13.96 | 17.64 |
| Valencia (modern) | 51.55 | 20.52 | 1.24 | 2.63 | 10.42 | 13.64 |
| Delft | 49.07 | 16.19 | 0.82 | 2.82 | 13.09 | 18.01 |
| Persian | 48.54 | 12.05 | 0.30 | 3.14 | 16.72 | 19.25 |
| Nevers | 56.49 | 19.22 | 0.71 | 2.12 | 6.50 | 14.96 |
| Rouen | 47.96 | 15.02 | 0.44 | 4.07 | 12.27 | 20.24 |
Of the potteries which hold a place between the hard and soft wares are the Palissy and Henri Deux. The composition of the former is 67.50 silica, 28.51 alumina, 1.52 lime, 2.05 oxide of iron, with a very slight admixture of alkalies. That of the latter is 59.10 silica, and 40.24 alumina.
From what has been said, it will be seen that the difference between earthen-ware, stone-ware, and porcelain is to be attributed to a few minor ingredients, to the preparation, and to the degree of heat to which they are subjected. The following table may be studied for the sake of making comparisons:
| Common earthen-ware... | Silica, 60; alumina, 30; iron, 7; lime, 2. |
| Blue clay... | Silica, 46; alumina, 38; iron, 1; lime, 1. |
| Staffordshire clay... | Pipe-clay, 40; kaolin, 25; quartz, 20; felspar, 15. |
| Stone-ware... | Felspar, 25; quartz or silex, 25; soda, 25; plastic clay, 15; boracic acid, 10. |
| Porcelain... | Silica, 66; alumina, 30; potash, 3.4; magnesia and lime, 1.1. |
| Porcelain glaze... | Silica, 73.4; alumina, 15.7; potash, 7.4; magnesia and lime, 2.2. |
| English porcelain... | Kaolin, 34; bone, 47; felspar, 19; soda ash, 36. |
| Old Sèvres soft-paste... | Saltpetre, 22; sea-salt, 7.2; burnt alum, 3.6; soda ash, 3.6; gypsum, 3.6; sand, 60. This was made into a frit and mixed—75 parts frit, 17 chalk, and 8 of calcareous marl. |
As to the glazes applied to clay or opaque ware, we have seen that they are broadly distinguished as translucent plumbiferous or alkaline, opaque stanniferous, and salt glaze. The distinction is also to be observed between glaze and enamel, although they are often confounded. Thus, according to M. Brongniart, there are three kinds of glaze—varnish, enamel, and couverte—all of which are vitrifiable. Varnish he describes as a transparent and plumbiferous material, melting at a lower temperature than that required for baking the paste; enamel, an opaque, generally stanniferous (containing tin) substance; couverte, a substance which melts at a temperature equal to that required for baking the paste. Birch, on the other hand, draws a distinction between glaze and enamel. In one place he speaks of “opaque glasses or enamels,” and again, “among the Egyptians and Assyrians, enamelling was used more frequently than glazing.” So, also, Fortnum, who, dividing pottery into soft and hard, subdivides the former into unglazed, lustrous, glazed, and enamelled. The glazed he again divides into silicious, or glass-glazed, and plumbeous, or lead-glazed, both of which are transparent. The word “glaze” is thus{64} more correctly applied to the covering, which does not alter the color of the body upon which it is laid, and “enamel” to that which obscures the body.
Glass, or silicious glaze, is formed by fusing sand with an alkali—potash or soda. When to this is added the oxide of lead, transparent plumbiferous glaze is the result; and when to both of these oxide of tin is added, we have opaque stanniferous enamel. The glass and plumbeous glazes may be colored with a variety of other oxides, without losing their transparency.
When or where glaze was first applied to clay is not known. Like many other branches of knowledge and many nations, it has its roots in the East, but whether we are indebted for it to India, Egypt, or Assyria, cannot now be decided. Upon this question Dr. Birch says:
“The desire of rendering terra-cotta less porous, and of producing vases capable of retaining liquids, gave rise to the covering it with a vitreous enamel or glaze. The invention of glass has been hitherto generally attributed to the Phœnicians; but opaque glasses or enamels, as old as the eighteenth dynasty, and enamelled objects as early as the fourth (B.C. 3000-2000), have been found in Egypt. The employment of copper to produce a brilliant blue-colored enamel was very early both in Babylonia and Assyria, but the use of tin for a white enamel, as recently discovered in the enamelled bricks and vases of Babylonia and Assyria, anticipated by many centuries the rediscovery of that process in Europe in the fifteenth century, and shows the early application of metallic oxides. This invention apparently remained for many centuries a secret among the Eastern nations only, enamelled terra-cotta and glass forming articles of commercial export from Egypt and Phœnicia to every part of the Mediterranean. Among the Egyptians and Assyrians enamelling was used more frequently than glazing, and their works are consequently a kind of faience, consisting of a loose frit or body, to which an enamel adheres after only a slight fusion. After the fall of the Roman Empire the art of enamelling terra-cotta disappeared among the Arab and Moorish races, who had retained a traditional knowledge of the process. The application of a transparent vitreous coating, or glaze, over the entire surface, like the varnish of a picture, is also referable to a high antiquity, and was universally adopted either to enhance the beauty of{65} single colors or to promote the combination of many. Innumerable fragments and remains of glazed vases, fabricated by the Greeks and Romans, not only prove the early use of glazing, but also exhibit, in the present day, many of the noblest efforts of the potter’s art.”
The use of oxides is also very ancient. The Egyptians employed that of copper for the production of their turquoise-blue, and possibly also for their green, manganese for violet, iron or silver for yellows, etc. The same processes were known in Babylon and Assyria. To the Persians and Arabians the application of metallic lustres was known at a very early period. Plumbiferous, or lead-glaze, was employed by the Babylonians, and the knowledge of its composition was in all probability imported thence among the Greeks, and by them may have been carried into Southern Italy.
The course of enamel is equally difficult of definition. Although used in Egypt, Babylon, and Assyria, it does not appear to have supplanted the lead-glaze; and for a long period all traces of it are lost, until it reappeared among the Arabs. We next meet with it as a distinctive characteristic of the potteries of Spain. It was also known to the Saracenic and Moorish potters of Sicily, and from either of these sources may have found its way into Italy.{66}