Mirrors were made by the ancients of polished metal and from slabs of black obsidian - a kind of natural glass. In mediaeval times they were made of clear glass behind which was placed a sheet of lead foil. Glass mirrors were made in Venice from the year 1507, when methods had been discovered of polishing the glass and of applying the "foglia," or layer of metal leaf, to the back. After this date the making of mirrors soon developed into great importance, and the "Specchiai," or mirror makers, had their own corporation. Like the other glass wares of Venetian manufacture, the mirrors were exported to all parts of Europe.

Some good examples of sixteenth-century mirrors and mirror-frames in glass cut into ornamental shapes, with bevelled edges and engraved, are preserved in our museums and in old houses.

Glass Painting For Windows

Glass Painting For Windows was known and practised in Venice as early as the fourteenth century. The very early Italian stained glass used in windows is said to have been executed for Leo III. in 795.

Besides the painted or stained glass used in church windows during the Middle Ages throughout Italy, there were glass manufactories in Rome, Verona, Milan, and Florence for the production of similar wares as those of Venice.

In France and Spain glass making was carried on at various places from the days of the Romans; antique fragments of glass have been dug up in Normandy and in Poitou. In the latter province glass making flourished from a very early date up to the fifteenth century. It was revived in 1572 by the Venetian Fabriano Salviati, who came to Poitou and set up a glass workshop. At Paris, Rouen, Normandy, and in Lorraine glass was made prior to the sixteenth century. The Normandy glass was of a coarse kind, made chiefly for windows and common utensils, but many of the Venetian varieties were made at the other places named.

Some Venetian glass makers came to Paris in 1665, when an establishment was formed for the making of mirrors, and about the same time another factory was set up at Four-la-Ville; these two factories were united by the French Minister Colbert, and were under the patronage of the king. We find that soon afterwards, and especially in the Louis-Quinze period, large panels and wall spaces were filled with glass mirrors as interior decorations.

Glass was made in Spain in the Ibero-Roman period, as the remains of glass vessels and necklaces have been found in tombs, and the ruins of Roman furnaces have been found in the valleys of the Pyrenees. It is supposed that the art was carried on under the Gothic kings of Spain, and also by the Moors in the thirteenth century, who brought with them glass workers as well as some of the wares of the East. Much of the glass made in Spain subsequent to this date is in imitation of the shapes of Arabian pottery, and this is still the case in much of the modern Spanish glass. Spanish glass of the Renaissance was similar in form and in material to the Venetian work of the same period, and during the seventeenth and eighteenth centuries the work was in imitation more or less of the contemporary Dutch and Flemish glass (Fig. 303).

In Holland, glassware seems to have been made by Murano artificers, who from time to time settled in that country and brought the secrets of their trade with them. The objects made were naturally imitations of the Venetian glass, and many of the Dutch drinking-glasses were very graceful in design.

In Amsterdam, Antwerp, Brussels, and throughout the Low Countries generally Venetian glass had been imported in great quantities in the time of and prior to the seventeenth century, and it is difficult to say how much of the old glass found at those places is Dutch, Flemish, or Venetian.

Engraving on glass was much practised in Holland, and many Dutch goblets have well executed portraits of kings, queens, and other persons.

Fig. 302. Venetian "Vitro di trina." (S. K. M).

Fig. 303. Spanish Glass; Sixteenth Century. (S. K. M).

Glass making has been practised in Germany, like in most European countries, from the days of the Romans downwards, especially in the Rhenish Provinces, but German examples dating from the Middle Ages are very rare.

There is documentary evidence which proves that glass was made at Mainz as early as the beginning of the eighth century.

The earliest example of German glass in this country is a wiederkom, or cylindrical drinking-vessel, which bears the date of 1571, but an older one, of the date of 1553, is preserved in the Knstkammer at Berlin.

A favourite decoration on the German Wiederkoms is the arms of the emperor or electors, those of the different states of the empire, and of private owners (Fig. 304).

The colour of this kind of glass is usually green and the decorations are enamelled or painted in grisaille; as a rule the German cups and wine glasses of the seventeenth century are richly decorated (Fig. 305). In the German wine-glasses known as "flugelgl*sser" is seen an imitation of the Venetian "winged glasses" (Fig. 301).

Bohemian Glass Of The Seventeenth Century

Bohemian Glass Of The Seventeenth Century is noted for its clearness and good quality, and illustrates the advancement made in the art of engraving on glass. The engraved work was done with a diamond point as in etching, with the lapidary's wheel, and by means of biting the glass with fluoric acid; the latter method is said to have been discovered by Henry Schwanhard of Nuremberg in 1670. John Sch*per was a very clever glass engraver and decorator of this period.

A beautiful kind of German glass is known as Kunckel's ruby glass, the originator of which was the director of the Potsdam glass works, where he produced this variety about 1680.