Page:Encyclopædia Britannica, Ninth Edition, v. 19.djvu/649

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MAJOLICA.] POTTERY 625 cities such as Venice also produced fine majolica, but of the later style. Materials. Fortunately ample information on this sub ject has been preserved to us. A potter of Castel Durante occupied himself for some time in writing a full description of the materials, the methods of using them, the "throwing- wheels," the kilns, and all the varied processes of his craft. His original MS., copiously illustrated with clever pen- sketches, is in the library of the South Kensington Museum, and the work was printed, with facsimiles of the drawings, at Pesaro in 1879. It is called / tre libri dell 1 arte del Vasajo by Cipriano Piccolpasso of Castel Durante, and is dated 1548. Piccolpasso himself did not produce lustrcd ware, but he describes the process and the special kiln it required ; his descrip tion of materials and methods, though not written till 1548, applies in all important points to the majolica of the second half of the previous century. Various receipts differing in the proportions of their ingredients are given ; the following examples are selected as typical instances. 1. The clay body, "terra," was to be, if possible, clay deposited by a river. It was carefully prepared for use by being beaten, ground in a mill, and passed through a sieve, so as to bring it into a smooth homogeneous plastic state, fit for being moulded on the wheel. It was all the better for being dug out a long time before it was used. 2. The white enamel, "bianco," was composed of thirty parts of "marzacotto " to twelve of oxide of tin. The mnrzacotto was simple powdered glass, a pure silicate of potash, made from clean sand and the alkaline tartar deposited by wine. According to Piccolpasso the decorations were painted on the enamel ground sometimes before it was fired, and sometimes after. This was an important difference. The enamel before firing formed a slightly granular and very absorbent ground, like clay in the biscuit state ; and the paintings on it had to be bold and broadly decorative, not delicate and miniature-like ; the touch of the brush had to be rapid and certain ; little or no alteration could be made, as the nnfired enamel sucked the pigment out of the brush and absorbed it below the surface. The earlier and more boldly decorative sorts of majolica appear to have been painted in this way on the unfired enamel, and owe much of their richness of effect to the fact that the different pigments have sunk below the surface of the ground. This process may be compared to that of painting in true fresco, while the painting on the fired enamel resembles the more deliber ate method of the painter in oil. After passing through the kiln the whole character of the enamel was completely changed ; it formed then a hard, smooth, non-absorbent, vitreous surface, on which the finest lines and the most minute paintings could be executed, and any part of it could easily be altered or wiped out. It was in great part owing to this change of method that the later majolica paintings became more pictorial and more minute in exe cution, the almost inevitable result of painting on a hard glassy ground. In some instances it is not easy to decide which method of painting has been adopted, though in most cases there is a dis tinct difference in the quality of the lines. One peculiarity is a sure test : when delicate patterns in white have been formed by covering the enamd ground with some colour, and then wiping out the pattern by using a pointed piece of stick or ivory on the soft pigment, in that case the enamel certainly was fired first. The colour could not be wiped cleanly out from an absorbent biscuit surface. Much of the delicate beauty of the Persian lustre paint ings, especially those on wall-tiles, is due to this method of getting minute patterns in white. It was also practised, though in a much more limited way, on some of the Italian majolica. The difference of handling between under-glaze " and over-glaze " painting cor responds exactly to that of the unfired and fired enamel ; but in the latter case another important difference is introduced : under- glaze pigments require much greater heat than those over the glaze and are consequently very limited in range of colour, while in majolica painting the same pigments were used in either case. 3. The glaze, "coperta," an ordinary glass, made more fusible by the presence of lead, consisted of oxide of lead 17 parts, silica (sand) 20, alkali 12, and common salt 8 parts. 4. Pigments, "colori," all owe their colour to a metallic oxide, yellow being derived from oxides of iron and antimony, green from oxides of copper and antimony, blue from oxide of copper, red from Spanish oxide of iron, Armenian bole, and red ochre, and black from black oxide of copper and manganese. Most of these had a certain proportion of oxide of lead, not to affect the colour but to make them more fusible. Other tints were produced by combinations of these pigments, and different gradations of tone were obtained by adding more or less of the ingredients of the white enamel. Methods of Manufacture. Piccolpasso gives sketches of the potters at work throwing vessels on the wheel. The wheel itself Manu- ("torno") consists of a vertical axle, with a large lower wooden facture. disk for the potter s foot to keep it revolving, and a smaller upper disk on which the clay was moulded by the potter s hands, an apparatus which differs in no respect from that used in Egypt under the Ptolemies, and is still employed in the great porcelain factory at Sevres. The potter to the right of fig. 55 is working with a wheel like that drawn by Piccolpasso. The earlier kind of majolica is almost wholly wheel-moulded, but during the 16th century a good many plates and vases were formed after shapes copied from silver-work, with sunk bosses or gadroons. These were formed by pressing thin disks of soft clay into moulds made of plaster ( " gesso "), bone-ash, and pounded marble. An elaborate description of the method is given in Piccolpasso s MS. Another practice also had arisen in his time, that of finishing the pottery on a joiner s lathe when it was dry, but before it was enamelled or fired, a practice unfortunately common at the present day, which makes the form of the vessel more mathematically correct, but greatly injures the freedom and spirit of touch given by the potter s hand. After the pottery was brought to the required shape it was dipped into a bath of the materials for the white enamel, finely ground and mixed with water ; and, after being allowed to dry, it was fired for the first time. The painted decoration was applied on the white enamel with brushes of various sizes, and the vessel was then dipped into a second bath of the glaze materials, finely ground and mixed with water like the enamel. It was afterwards fired a second time. If it had lustre colours, they were put on over the glaze, and a third firing in a different kiln was necessary for the reasons explained above under the head of "Persian pottery." The application of the transparent glaze over the enamel was not absolutely necessary, and was occasionally omitted, but the finer sorts of majolica usually had it for the sake of the increased brilliance which it gave to the non-lustre colours. The kiln for the ordinary colours and first two firings, as drawn by Piccolpasso, is exactly the same in principle as that used by the potters of ancient Greece and Rome, that is, an arched chamber in two stories, with a perforated floor between the lower compartment for the fire, the upper for the pottery. A sketch is also given in Piccolpasso s MS. of the lustre-kiln, in which the pottery is enveloped in flames and heated smoke. Fig. 55, from a Venetian woodcut of the middle of FIG. 55. Two forms of Italian potter s wheels, about 1540. the 16th century, shows majolica potters at work throwing pots on the wheel. Two different wheels are being used ; the man on the left keeps his going by giving it a succession of spins with one hand, the other works his wheel by the help of a lower foot- turned disk. To the extreme left a small kiln is shown ; the lower arched opening is for the insertion of the fuel, the upper for the pottery ; the holes at the top are for the escape of the heated air and smoke. Styles of Decoration. In general character the painted Decora- decoration on the majolica of the latter part of the ISthtion. and beginning of the 16th century is very different from that of a few years later. The first retains much of mediaeval purity and simplicity of design, while the later sort follows the richer and more florid style brought into fashion by the rapidly -approaching decadence of art. The principal variety of the early class is the ware painted in blues with a yellow lustre, manufactured chiefly in the workshops of Pesaro, Gubbio, and Deruta. With these two simple colours effects of the greatest decorative beauty were produced, far more truly artistic and suited to their special purpose than the elaborate pictures in many colours painted some years later in the workshops of Urbino and Durante. In the firm precision of the drawing and extreme skilfulness of touch in the blue outlines one is reminded of the paintings on Greek vases of the best period. Some of the large plates of this ware have

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