How China Cups and Saucers are Made
Cups and saucers, dinner plates and all of the other useful and beautiful articles of chinaware which we use in our homes are so familiar to us that we do not realize the knowledge, art and skill that have gone into their making. The art of making them and the materials of which they are made have had a long, romantic history.
Chinaware, or porcelain, pottery, bricks and tiles, drain pipes and flower pots are all made of clay, shaped and then fired or burned, but they are otherwise quite different from one another, both in substance and in the way they are made. Dishes, in which we are particularly interested, are of three general kinds: vitreous, semi-vitreous and earthenware or pottery.
The word “vitreous,” which means “glassy,” is used to identify true porcelain, of which the finest dishes are made. It is extremely hard, because of the high temperature at which it is fired. It is translucent, which means that if you hold a piece of it up to a strong light, the light will show through the thinner parts. Also, if you tap the edge of a porcelain dish with a pencil it will give forth a clear, ringing sound.
Semi-vitreous dishes are much used by restaurants, and for ordinary daily use at home. They are not so hard as vitreous dishes, light will not show through them, and they make a duller sound when you strike them. Both kinds of dishes come in pretty shapes and designs, but you can always tell which kind a dish is by holding it up to the light and by tapping it to see if it rings clearly. Many manufacturers have the word “vitreous,” or “semi-vitreous” printed on the under side of each dish.
Earthenware is coarser than semi-vitreous ware, and much more brittle. It is quite opaque, that is, it will not let the light through, and if you tap it the sound will be dull and flat. Earthenware comes in several different grades. Many attractive pieces are made of it, including vases, jars, bowls, breakfast, tea and dinner sets.
The making of pottery is one of the oldest arts known to man. It is so ancient that no one knows what people first learned to make vessels of clay. In our great museums we may find well shaped bowls and vases which were buried in the graves of the Egyptians perhaps six thousand years ago, and which have helped us to learn something of the state of civilization in Egypt long before the time of Moses. The ancient Cretans and the Greeks made wonderfully beautiful jars and vases thousands of years ago. The As- Syrians and Persians were noted for skill in this work, and Roman pottery has been found everywhere within the limits of that great empire. The Egyptians knew how to make a beautiful glaze for their pottery thousands of years ago. Some students think that they were the first people to learn the art of glazing, and that it was taught by them to the Babylonians and Assyrians. It is believed that the Greeks knew nothing about glazing.
As we have learned, the civilization of Greece and Rome was almost swamped for a time by the rush of barbarian peoples from the north. These peoples knew little about the making of pottery, and the potter’s work that was done in Europe in medieval times was very crude. The knowledge which had been gained during centuries by the Egyptians, the Greeks, the Assyrians and Persians lingered on in Egypt and Syria. After the Moslem conquests the art was revived, and beautiful pottery was made by some of the Moslem peoples.
When the Moors overran Spain they brought with them skilled workers in various crafts, among whom were potters. Knowledge of the art of these Moorish potters soon spread through Europe. Potters of other nations were quick to learn it and improve upon it, and soon potteries sprang up in other countries. Many beautiful things were made, especially in Italy, but they were made from heavy clay.
Long before this time the Chinese, working by themselves, had learned to make fine pottery. In their search for fine clay they found a kind of clay which, when mixed with other ingredients and fired, became what we now know as porcelain or china. The Chinese named this clay kaolin, from the Kao Ling Hills where it was first discovered. The name “porcelain” came from the Italians, who called the Chinese ware porcellana because its satiny surface was like a porcelana, or cowrie shell. It is amusing to know that this shell got its name from the word porcella, “little pig,” because of its shape.
Just when porcelain was first made is not known. Some people believe that it was being made in China before the Christian era, but the earliest known pieces date from about the tenth and eleventh centuries, A.D.
Thus we know that, while Leif Ericson was exploring the coast of North America, and while William the Norman was conquering England, Chinese artist-craftsmen were producing fine porcelain. By the time that Chaucer made his journey to Canterbury with the pilgrims, Chinese potters were supplying the Ming emperors with porcelain that is today worth a king’s ransom.
The Chinese taught the art to the Japanese, and for centuries no other people was able to imitate the ware of these two countries. Traders and travelers brought examples of this porcelain to western Asia and northern Africa, and some of it was brought to Europe from Cairo as early as the twelfth century. European potters tried hard to discover what clay it was that gave the Chinese porcelain its hardness and whiteness, and many experiments were made.
Some of what we now call “soft paste” porcelain is said to have been made in Venice in 1470, by an alchemist, Maestro Antonio, and what is known as the Medici porcelain was made at Florence in the last years of the seventeenth century. This was very beautiful ware, but it lacked some of the qualities that the kaolin gave to the Chinese porcelain. It was not until 1709 that kaolin was discovered to be the long-sought clay. The discoverer was a chemist named Böttger, and he is said to have found it in the clay used to whiten his wig. Böttger lived at Dresden, but he moved to Meissen, where he made the famous Dresden china. He tried to keep his discovery secret, but in vain. In a few years porcelain was made in other countries of Europe, and French, Italian and Austrian porcelain also became famous. It received its common name of china because it was first made in that country.
While clay has always been the chief ingredient of porcelain, other materials are used with it. Among these are feldspar, ground quartz, calcium carbonate in the form of chalk, and sometimes calcium phosphate in the form of bone ash. The kaolin, or china clay, does not melt and become transparent, but some of the other things, such as the feldspar, do. If you were to look at a piece of porcelain through a microscope, you would see a glassy substance packed full of opaque sticks of kaolin. When the light rays try to find their way through the glassy part of porcelain, they are reflected back and forth among these sticks, and it is this that gives fine porcelain its soft translucence.
Early in the eighteenth century lovely china began to be made at Sevres, Chantilly and Vincennes in France, and at Stratfordle-Bow, Chelsea and Derby in England and in many other places in these and other countries. Each manufacturer developed his own formula for making the paste. There were three general types of porcelain made, “hard paste,” “soft paste” and “bone paste.” Soft paste porcelain is very lovely, but is slightly porous. Most modern china is made of some variety of hard paste or bone paste. It was the development of bone paste that first brought about quantity production of fine china. The English potters, sometime about the middle of the eighteenth century, found that a fine, hard china could be made at a low cost by adding bone ash to the mixture.
China and earthenware were brought to America in the colonial period and in the early years of the Republic by ship-loads. Most of this ware was English, and so important was the American market that some of the potteries made a specialty of china and fine earthenware with American patriotic and scenic designs. These are now eagerly sought by collectors. A factory for making bone china was started in Philadelphia in 1769 by two men, George Anthony Morris and Gousse Bonnin. Bonnin is believed to have learned his trade at Bow. The business was closed three years later for lack of money to carry it on, though these unfortunate pioneers had tried in many ways to raise the necessary funds. In 1771 they had appealed to the Pennsylvania Assembly for a loan, and later they had set up a lottery, but they could not get enough money to carry on. Another Philadelphia pioneer in the making of china was more successful. William Ellis Tucker, a Quaker, opened a factory in 1825 for the manufacture of hard paste chinaware. This business flourished for more than twenty years. To-day much fine china is made in the United States, besides semi-vitreous ware and clay products of every imaginable kind.
Many things happen to the clay after it has been taken out of the ground, before it is ready to make a dainty cup and saucer, a graceful vase, or any of the numerous other things that are made of china. To take out any sand that may be in the clay after it is quarried, it is mixed with water and strained through a fine sieve into a tank, where it is allowed to settle, and the water is drawn off. The clay is then put into filters, the water is pressed out, and the clay is ready to be shipped to the pottery. It is not yet ready for the potter, however, and the processes through which it has to go depend upon how it is to be used.
To make fine china, the kaolin is mixed with other materials and water is added. After it is thoroughly mixed it is freed of any remaining impurities by straining and by means of electric magnets to remove particles of iron. When it has been mixed to a thick, creamy paste that can be molded into any shape, it may either be used at once, or it may be filtered and pressed again, and folded away in a dark place for later use. Some potters put it through still another mill to press out any air that may be in it.
Valuable vases, and many other things, are still made on the potter’s, or throwing, wheel. This is a contrivance which was probably used in Egypt six thousand years ago and has been very little altered in principle since. The potters of Babylon and Nineveh used wheels very much like it, even before the Bible was written. The throwing-wheel is a disk which revolves horizontally in a pan. The pace at which it moves is fixed by a brake which the potter controls. The wheel is still sometimes worked by the potter’s foot, but most of the wheels used in large potteries are worked by electricity.
As the throwing-wheel spins round on its axle, the potter throws the clay, which sticks to the wheel and goes round with it. Then the art of the potter comes into play. As the wheel spins he presses, and pulls, and molds it with his skillful hands or with tools made for the purpose. He works from the base upward, shaping the walls, making them the right height and thickness, and gradually the clay takes on the desired shape. When it is finished, the vessel is set aside to dry, so that it can be fixed on a lathe, and turned and smoothed. Plates, bowls, cups and other round pieces are made on a wheel that is shaped to mold the face of the article, while a steel tool is held so as to shape the back of the article. This process is often called “jiggering.”
Many articles, such as teapots, handles and oddly shaped pieces, cannot be made on the wheel, but are “cast’ in a plaster of Paris mold. A thin, cream-like mixture of clay called “slip” is poured into the mold and allowed to stand. The water in the slip is absorbed by the plaster of Paris, leaving the clay on the inside of the mold. The longer it stands, the thicker the clay will be. When it has reached the desired thickness, the remaining water is poured off and the cast is allowed to dry. Then it is taken from the mold, trimmed and smoothed. Cup- handles, spouts for teapots and other things of the sort are made in separate molds and stuck on with a little of the slip. There is a third method called “pressing,” in which the clay is placed on a one-piece mold and hammered into shape with a hand batter. All of these methods require skill and experience, and though machinery is used as an aid to the potters, eighty percent of the work in a pottery is hand work.
After the clay has been shaped, the vessels are put in a drying room, and then comes the delicate and difficult process of baking, or firing, the clay to make it into porcelain. For this purpose the china is packed into closed earthenware boxes called saggers, in such a way that they will not touch one another. The saggers are packed into a kiln (pronounced kill), which is a kind of furnace, and heated until the temperature has reached as high as 1,500 degrees Centigrade. The kiln is kept at this temperature for about ten hours, and is then allowed to cool so gradually that it is three or four days from the time they are put in before the saggers are opened and the “biscuit,” as it is now called, is taken out.
The dishes are now ready for glazing. The pieces are dipped in a kind of liquid glass called “glaze slip,” which leaves a thin, even coating all over the biscuit. Then they are put into another kiln and fired at a temperature hot enough to fuse the glaze and the biscuit and give the china a softly shining surface.
Some china is decorated before the glaze is put on, and this we call “underglaze” decoration. There are various ways of applying it to the biscuit. One method is to make the design in one color, by means of copper-plate printing. “Overglaze” decoration is more elaborate, and may be painted by hand or by decalcomania. In this latter process, the design is lithographed on a special paper which is pressed on the china in such a way that the whole design is transferred to it. If gold is used, it is usually applied to the smooth surface of the glaze, just as the colors are. Etched, or encrusted, gold decorations are made by cutting the design in the glaze with acid, and then covering it with gold. When the gold has been burnished the high parts of the design are bright against the duller sheen of the low parts, giving a very rich effect. After the colors and gold have been applied, they are set, or fused with the china by another firing. Quite lovely raised designs are sometimes made by pressing or building them on the clay before it is fired.
