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been the earliest and until the fifteenth century the only means known of glazing soft pottery.

We have seen that a certain amount of lead has been found in some of the blue coloured glazes of Babylonia, and (says Dr. Percy) “probably employed as a flux;” if so, this might have been the spring of its general adoption for the purpose of producing a more easily fusible and therefore a more ready and more manageable coating; but in the east it does not seem to have supplanted the more elegant and purer siliceous glaze.

Fragments of Græco-Roman pottery from Tarsus, lamps from the neighbourhood of Naples, and other examples of a highly glazed pottery from various antique sites which have all the appearance of a plumbeous composition, are preserved in many collections, as at the Louvre, Naples, the British museum, &c. The paste of which these examples are formed is to all appearance an ordinary potter’s clay, generally of a buff colour, and in no way similar in character to that of the Egyptian or Assyrian wares, glazed with a true glass. The adhesion of the vitreous coating to the surface, and its perfect adaptability to the irregularities of the shaped and moulded pieces, prove its affinity for the paste of which they are made, and indirectly that its composition is not the same as that of the Egyptian or Assyrian glaze.

It is worthy of remark that nearly all these specimens are found in the south of Europe, examples rarely occurring even at Rome; and, indeed, it is not improbable that the use of this glaze had hardly been adopted by the artistic potters before their art, together with all others, had degenerated under the Lower Empire. The superabundance of the precious metals and other rich material, more appreciated by the powerful than the priceless treasures which art had formed from common clay, and which had been the delight of a more refined state of society, led finally to a total neglect of the higher branches of ceramic manufacture.

It is not unlikely that plumbeous glaze may have been introduced by Greek or oriental potters into southern Italy. We learn from the monk Theophilus that the art of decorating fictile vessels with vitreous colours was practised by the Byzantine Greeks, who would have carried it there. This statement, in all probability, refers to the lead glazed wares and not to the tin enamel, the former of which, as we have seen, was known earlier than his time to the potters of Tarsus, Pompeii, &c., and it is reasonable to believe that the art may have been preserved in Byzantium when lost, or nearly lost, in Italy. Perhaps, in combination with incised ornament the use of this glaze never ceased in that country from the eighth and ninth centuries until the introduction or discovery of the stanniferous enamel in the fifteenth century; and we find that the earliest glazed wares of that country, the sgraffiati, the painted, and the mezza maiolica wares, are covered with this description of vitreous surface.

In the eleventh century churches built in various places were decorated with discs and “ciotole” of glazed and painted terra-cotta. The researches of the abbé Cochet at Bouteilles have shown that glazed pottery was in use in the north of France in the Anglo-norman period of the thirteenth and fourteenth centuries, or perhaps even in earlier time. Examples of glazed and painted tiles of the fourteenth century are preserved in the British museum. As before stated, this glaze is composed of silica with varying proportions of potash or soda and of oxide of lead, by which addition it is rendered more easily fusible but remains transparent.

To obtain a white surface was, however, desirable, the colour of the paste beneath the glaze being generally of a dull red or buff and ill-adapted as a ground for the display of coloured ornamentation. To supply this want, before the invention of the tin enamel, an intervening process was adopted. A white argillaceous earth of the nature of pipeclay was purified and milled with water, and thus applied over the coarser surface of the piece in the same manner as the glaze: again dried, or slightly fixed by fire, it was ready to receive the translucent coat through which the white “slip” or “engobe” became apparent. It is easy to conceive that by scratching a design or pattern through this white applied surface to the darker clay beneath, before fixing in the fire, a ready mode of decoration presented itself without the use of colour, to be covered with but visible through the glaze; hence the early incised or “sgraffiato” ware, one of the primitive modes of decorating glazed pottery.

Passeri states that pottery works existed from remote periods in the neighbourhood of Pesaro, as proved by remains of furnaces and fragments of Roman time and tiles with the stamp of Theodoric; that during the dark ages the manufacture was neglected, but that it revived after 1300, and that it then became the fashion in that city to adorn the church towers and façades with discs and “bacini” of coloured and glazed earthenware; a practice which had been in use at Pisa and other cities as early as the eleventh century. The origin of this custom has been much discussed; and the reader will find an account of it in the introduction to the detailed catalogue of Maiolica in the South Kensington collection. Occasionally, or rather frequently, circular and square slabs of porphyry and serpentine were used on the same building, concurrently with the glazed earthenware, as on the tower of Sta. Maria Maggiore at Rome; and, indeed, this mode of enrichment attached to the architecture of the 11th, 12th, and 13th centuries is in accordance with that produced by the enamelled discs and inlaid stones on processional crosses and church plate of the same period.

The only instance, observed by the writer, of the occurrence of these “bacini” of glazed ware in domestic architecture is seen over the windows of the palazzo Fava in Bologna. This style of decoration ceased entirely during the course of the fourteenth century.

Passeri instances the use of glaze on tiles upon a tomb in Bologna, opposite the church of S. Domenico, dated about 1100; and he further states, but we know not upon what authority, that it was about the year 1300 that the method of covering the clay with a “slip” or “engobe” of white earth, or the coarser earth of Verona, was first adopted. Slightly baked, it was glazed with “marzacotto” (oxide of lead and glass), applied wet and again fired; and this glaze was variously coloured yellow, green, black, and blue, by iron, copper, manganese, and cobalt. A similar method of coating the rough and porous baked clay seems to have been known also at a very early period in the north of Europe, and to have been in use throughout France, Germany, and England.