painting pictures in which the shadows were the local colour
- l!l..l. the lights white. As p.1intin,._: advanced it gradually
approached more nearly to the scale of colour of the glass- painter, the lights instead of being white were painted cf appropriate shades of the local colour, and the shadows were graduated into black in their deepest parts. It may have been that glass painting suggested this important change in ideas of colour and chiaroscuro. The glass being painted as drscribed must be burnt to fix the enamel thereon with its flux. The separate pieces with the painted side upwards are placed upon the shelves of a kiln or iron box, covered with whiting ; the kiln is placed in a brick oven, and a fire kindled which surrounds it with flames. Much experience (SL.-SS ' oll'cn-.lc-rs I [GLASS r.u."r1.'u. The Italians have not been impelled to this lamentable destruction of these precious records and Leauti- 'ful creations by any of the convictions, changes of faith, ' favouring this incrustation. is needed to determine when the glass is sulliciently burnt l to fix the enamel. When this has been done the fire is withdrawn, the oven is hermetically sealed, and the glass is left to cool gradually, so as to be annealed. From the appearance of nuny Italian win~.lows as compared with those executed elsewhere, it is reasonable to infer that the Italians were less skilful than their northern contemporaries , in firing their glass. The next process is to unite the numerous pieces of I1l0S1lC, thus painted and burnt, into panels of a given size, which is done by means of ribbons of lead grooved on both sides, the ribbons being soldered at all their angles, thus firmly tying the mosaic together. Vhen the painted window is erected, the leads are seen internally in contrast with the transparent glass as intensely black lines, but externally, where they catch the light, as meandering lines of metal dividing the surface. Mistaken attempts have repeatedly been made to get rid of these lines, but they are constituent parts of the art, can only be got rid of by changing its true character, and are only disfigur- ing when injudiciously introduced, as for instance in some 14th-century glass in Santa Croce, in which the white of the eyes are fixed with leads of the form of spectacles, so that all the saintly persons represented appear, ridiculously enough, to wear these aids to defective vision. The panels, which are technically called glazing panels, are inserted in their plaees in the windows by means of grooves prepared in the stone work, into which they are secured with cement and strengthened at intervals with cross bars of iron called saddle bars, to which the glass is made fast by ties of copper wire. Thus fixed, experience has shown that painted windows if duly cared for will last for many cen- turies. Regarded in their connexion with past history, no monuments of art surpass painted windows in interest ; they are only equalled by the paintings still extant in the tombs of the Egyptians as illustrations of faith, history, and customs. It was almost the universal usage that persons of every nnk and position, as well as corporate bodies and guilds, nude offerings of painted windows to churches. Whilst they give the most vivid ideas of ancient taste and methods of decoration, the religious opinions of successive ages are interpreted by the manner in which sacred subjects are selected or represented ; the actual state of art at different times, from its rudest forms to the most perfect, is admirably exemplified; and, as it was customary to introduce the donors in appropriate parts of their gifts, the prince or noble in knightly panoply, with his armorials, is seen kneeling, sometimes accompanied by his spouse. In like devout attitude the ecclesiastic appears in the robes and with the insignia of his ofiice, or the wealthy merchant and his wife in appropriate costume. In other examples t1ades- men, surrounded with the objects and materials of their commerce, sell to their customers articles of clothing or of food. Every occupation is illustrated in these ancient pictures in glass. How great then has been the loss to art and history caused by the reckless demolition of painted glass which has taken place in all parts of Europe, but especially‘ in Italy, where the clergy have been the chief , faces. or fanaticism, fatal to so many works of art in other coliti- tries, but by unreasoning transformations of taste, by ignor- ance, or by the paltry desire of gain. In northern climates ancient glass is found to have been affected by the action of the weather, its outside surface is roughened and pierced to a small depth by little pits, or is so altered as to resemble sheets of zinc ; it is also covered with dirt, especially inter- nally, the enamel rougher than the surface of the glans These injuries and accumula- tions veil the glass paintings, and produce a mysterious confusion of form and colour, admired by many, who to obtain in modern work such effects of age, and to conceal the inharmonious crudity of colour, soil it artificially with varnish, paint, or enamel applied externally, or v. ith dirt applied of set purpose, showing thereby their ignorance of art and their bad taste, by having recourse to processes which are outside the domain of art, for perfect harmony of colour and effect of chiaroscuro ought to be the results of the artist's cultivated knowledge and skill, and nothing should be done to hasten the obscuration of the windows cr to anticipate the effects of time. Important improve- mcnts have been made in the art of glass painting, as well as in the manufacture of glass, since Theophilus wrote his treatise, but some of these have not been favourable to the art ; for instance, old glass is much quieter in colour than modern, and as it was less diaphanous, and less smooth in texture, it was better adapted to the operations of the glass—painter. This being observed, eminent manufac- turers of coloured glass in England and on the Conti- nent have prepared imitations of the soft, pleasing hues of old glass, and of its varied texture, with considerable success. The addition of an enamel brown from iron, and m11ch warmer in tone than that made from copper, has been an important aid to glass painting, whilst about the middle of the 16th century numerous coloured enamels were invented, which, however ingenious and beautiful, subsequently modified the art unfavourably. Vehicles composed of spirits of turpentine, fat turpentine, or gum senegal have arlvantageously replaced the primitive distempers already alluded to. An important addition was the discovery of the yellow stain, made from silver, the only purely transparent colour applicable to the surface of glass. It has been described as the invention of the Bt-ato Giact-mo of Iflm, who practised glass painting at Bologna, and died in the odour of sanctity in 1491 ; but the yellow stain was characteristic of glass paintings for more than a century before his time. The introduction of the system of coating white with coloured glass in the same way as it had been coated with ruby glass, and the invention in the 15th cen- tury of removing portions of the coloured glass by abrasion or with the wheel so as to lay the white bare in conformity with special designs, together with the practice of staining such white portions yellow, led to important modifications in the art. Embroideries on coloured garments and other ornaments were thus easily represented, and the system is very useful in painting heraldry. Instead of the wheel fluoric acid is now chiefly used to remove the film of coloured glass from its white backing. The leads with which the mosaic of glass is brought together in glazing panels have undergone various changes. Early lead-work is massive; but at the beginning of the l5th century it becomes lighter in appearance but without loss of strength, for although the grooves were made shallower, the lead was increased in thickness and was rounded on the outer sur- Alterations also were made in the method of fixing painted windows: the saddle bars, according to climate,
were made more or less robust ; and, instead of crossing the