GLASS, PAINTED OR STAINED. There are two kinds of painted glass known in modern times, Enamel and Mosaic glass. In enamel glass proper certain fusible pigments are painted on a sheet of white glass, which is then fired, and the result is a picture the tints of which even in the high lights are not wholly transparent. A modification of this method produces its picture partly by enamelling on white glass, partly by the use of pot-metal glass (i.e. glass coloured while in a state of fusion, and therefore of the same tint all through), the colour of which is heightened or modified by the use of enamels. In this style, if any junction between two pieces of glass becomes necessary, the lead calms used for the purpose are studiously concealed by being made to run along leading lines of drapery or other forms in the picture. The object of this enamel and semi-enamel glass-painting is the closest possible imitation of an oil or water-colour picture; and the results of it are never satisfactory. For at the best it can only do with difficulty and imperfectly what the oil-painting does with ease and perfection; while at the same time it refuses to avail itself of the special characteristics of glass, which can produce effects that no opaque painting can approach. This imitation of easel or wall pictures also leads the designer into making designs unfitted for the ornament of windows, and wandering from their true purpose of decoration. Indeed, not infrequently the work of a great master in picture-painting is taken as a model for a stained-glass window, and laboriously and servilely imitated, with the result that a mere caricature of the great work is produced, which is as far as possible from being an 'ornament' to the building in which it is placed.
The only method capable of producing stained glass which shall be beautiful and interesting, and which at the same time can plead some reason for its existence, is that which has been called mosaic glass, the process of which very briefly stated is as follows:
A design is made wherein the drawing is given and the colours indicated, which is the working-drawing of the glass-painter. From this working-drawing a kind of map is made which gives all the various pieces of the mosaic. The glazier cuts these pieces out from sheets of glass of various colours, and hands them back to the painter, who proceeds first to paint the leading lines with a solid opaque enamel, the colouring matter of which is an oxide of iron. This being done (and the glass sometimes having been fired at once, but sometimes not), the pieces of glass are stuck together temporarily (by means of wax) on a glass easel, and the painter slightly shades his bold traced lines with the same opaque colour; using sometimes washes (in which case, of course, the colour is much diluted, and is only semi-opaque), and sometimes hatching of lightly laid-on lines, as in a black and white drawing on paper. Sometimes both washes and hatching are used, and sometimes the washed shadows are 'stippled'—i.e. part of the colour is removed by dabbing it with the end of a broad brush. In any case the object of the methods of shading is to keep the shadows as clear, and to dull the glass as little as the explanation or expression of the subject will admit of. Two or three or more firings are necessary during the process of this painting, but as far as the painting is distinguished from the mosaic is concerned this is all that has to be done, though it must be said that to do it well requires considerable experience and artistic skill and feeling.
This painting being done, the glass goes back to the glazier's bench again, and he 'leads it up' (i.e. joins it together with lead calms soldered at the junction), and the window, after having been solidified by a stiff cement or putty rubbed into the leaf of the leads, has then only to be put in its place and strengthened by the due iron stay-bars. It may be mentioned here that in this mosaic glass-painting, so far from there being any necessity for concealing the 'leads,' it is highly desirable to break up the surface of the work by means of them, always taking care that their direction is carefully considered from the point of view of their appearance. The obvious strength which the network of leads gives to the window on the one hand, and the obvious necessity for picking out small pieces of exquisite colour on the other, take away all sense of discomfort in the arbitrary disposition of these constructive lines.
A mosaic stained-glass window, therefore, seems a very simple affair, and so it is as a process (bating some difficulties in the making of the material). Its real difficulties are all on the artistic side, and have to do with the qualities of design and the choice of material.
As to the design, it must be repeated that suggestion, not imitation, of form is the thing to be aimed at. Again, the shading is, as above said, for the sake of explanation, not to make the work look round, and also for diversifying the surface of the glass, to make it look rich in colour and full of detail. The qualities needed in the design, therefore, are beauty and character of outline; exquisite, clear, precise drawing of incident, such especially as the folds of drapery. The whole design should be full of clear, crisp, easily-read incident. Vagueness and blur are more out of place here than in any other form of art; and academical emptiness is as great a fault as these. Whatever key of colour may be chosen, the colour should always be clear, bright, and emphatic. Any artist who has no liking for bright colour had better hold his hand from stained-glass designing.
Consideration of the colour of the work naturally leads to consideration of the material. The ordinary machine-made window-glass, thin, and without any variety of surface, is wholly unfit for stained glass, but it should be stated in passing that a modern mechanical imitation of the unevenness of surface found in old glass, which is commonly called 'cathedral glass,' is the worst of all materials for windows, and should never be used in any kind of glazing, ornamental or plain. The due varieties of surface are those that occur naturally in the process of making thick cylinder or crown glass. All glass used for glass-painting should be very thick, or, whatever the pigments used for colouring may be, the effect will be poor, starved, and, if bright colours be used, glaring. The glass which has to show as white should, when laid on a sheet of white paper, be of a yellowish-green colour; for the colours in stained glass are so powerful that unless the whites are toned in the material itself they will always be inharmonious and cold.
It is necessary in addition to state briefly what the varieties of coloured glass proper for the purpose are. First comes pot-metal, in which the colour is an integral part of the glass; then flashed-glass, where the colour forms a coloured skin to a white body; * and lastly a transparent yellow stain (deduced from silver), which attacks the silica, and thus forms a part of the glass, is much used to colour portions of the pot-metal, for ornaments on dresses, hair, flowers, and the like.
This art of mosaic window-glass is especially an art of the middle ages; there is no essential difference between its processes as now carried on and those of the 12th century; any departure from the medieval method of production in this art will only lead us astray. It may be added that its true home was northern Europe during the middle ages, as the importance of the wall-pictures in Italy made its fullest development less necessary to the buildings in that country, and accordingly the Italians did not understand its principles so well as the artists of France and England, and had not the full measure of unerring instinct which the latter had. And besides, as Gothic architecture lasted longer with us and the French, there was more opportunity for the development of the later styles here, since the neoclassic architecture had scarcely a place for stained glass.
The 12th century begins the real history of the art. The windows of that date that are left us are very deep and rich in colour, red and blue being the prevailing tints. They are mostly figure designs, disposed in ornamental frames, and are admirably designed for their purpose; the painting is very simple, nothing but a little washed shading supporting the traced lines; the figures are usually small, except in the case of windows far removed from the eye, as in some of the windows at St Denis near Paris. The beautiful windows in the choir aisles at Canterbury Cathedral are usually referred to the 12th century, but if they belong to it they must be of its later years.
There was a slow development of the glass all through the earlier years of the 13th century, and a great deal more work is left us of that period; a great deal of the glazing of the early pointed architecture was of mere geometrical work. The ignorant architect, Wyatt, who gutted Salisbury Cathedral in 1790, found most of the windows so glazed, and destroyed the glazing except for a few fragments. The window of the north transept at York Minster, now called the 'Five Sisters,' is a well-known example of this beautiful work.
The 14th or end of the 13th century invented a very beautiful kind of glazing especially suitable to the large traceried windows then coming into vogue; in this style bands of very richly coloured figure-glass, usually framed in canopies, run across the lights, and are supported by ingenious fret-glazing in white, on which elegant running patterns are freely drawn, and this grisaille (as it is called) is connected with the richer-coloured bands by means of borders, and with medallions, little gem-like pieces all carefully patterned; the whole producing an effect of singular elegance and richness, and admitting plenty of light. The nave aisles of York Minster and Merton College Chapel at Oxford may be cited as giving us very perfect specimens of this glazing, which may be said to be the highest point reached by the art.
With the change to the Perpendicular style in the 15th century came a corresponding change in stained glass, though, of course, that change was very gradual. The glass now had a tendency to become paler in colour; a great part of the great traceried windows of the style was oftenest made up of elaborate canopies, in which white touched with yellow stain played a great part. Some very beautiful windows of this date are almost entirely carried out in silvery whites and yellow stains. The shading of the figures and drapery, &c. was much more elaborate; the stippling and hatching above mentioned was common, especially in the later part of the style; but the luminous quality of the shadows was generally well maintained. In spite of the ravages of the Puritans both of the Reformation and of the Cromwellian episodes, examples of stained glass, usually very fragmentary, are common throughout England. The antechapel at New College, Oxford, the great east window of Gloucester cathedral, many windows in the choir of York Minster, and many of the parish churches in that city, notably All Saints, North Street, are splendid examples of the work of this period.
In the 16th century the art was on the wane: it became heavier in shading, less beautiful in colour, and aimed too much at pictorial effect. As a reasonable art stained glass can hardly be said to have existed after about 1540; a few pieces of rather pretty and fanciful glazing and a little heraldic work are in the Elizabethan period all that represent the splendid art which adorned such buildings as York Minster and Canterbury Cathedral. The windows of Fairford Church, in Gloucestershire, form a very interesting collection of the work of the earlier part of the century. King's College Chapel at Cambridge is almost entirely glazed with picture-work of this period. It has suffered much from reglazing, and is now very hard to read; nor could the art in it have ever been of a very high order.
With the ruin of Gothic architecture stained glass was swept away entirely; and indeed it perished sooner and more completely than any of the other subsidiary arts, doubtless because its successful practice depends more on the instinctive understanding of the true principles of decorative art than any other of the arts connected with architecture.
The art of glass-painting has been revived with the eclectic revival of Gothic architecture, which is such a curious feature of our epoch, and has shared to the full in the difficulties which an eclectic style must of necessity meet with. Still it must be understood that glass-painting is no 'lost art' in the sense of its processes being forgotten: whatever the deficiencies of the modern art may be, they are the result of the lack of feeling for decoration, rather than of difficulties as to material, workshop receipts, and the like. The very praiseworthy studies of Mr Winston and his collaboration with Messrs Powell of Whitefriars in the manufacture of window-glass fit for the purpose made it possible for us many years ago to produce good stained-glass windows if our artistic powers did not fail us, or rather if they could be turned into the right direction; if the designers could understand that they should not attempt to design pictures but rather pieces of ornamental glazing which, while decorating the buildings of which they formed a part, should also tell stories in a simple straightforward manner.
This they have in a great measure learned to understand, and the public also are beginning to see that the picture-window of the semi-enamel style (as represented chiefly by the elaborate futilities produced by the Munich manufactories) cannot form, as a window should do, a part of the architecture of the building. On the other hand, there has been (unavoidably doubtless) too much
* Flashed-glass is mostly used for the beautiful 'ruby' glass deduced from copper, the making of which was revived by Messrs Powell of Whitefriars, in London, with the help of Mr Winston about the year 1853.
mere copying of medieval designs; it has been forgotten that the naïvetés of drawing of an early stage of art which are interesting when genuine and obviously belonging to their own period, become ridiculous when imitated in an epoch which demands at least plausibility of drawing from its artists. But that very demand for plausibility and the ease of its attainment form another snare for the stained-glass designer, whose designs, though made with a knowledge of the requirements of the art, and though not actually imitative of medieval work, are too often vacant and feelingless, mere characterless diagrams, rather than the expression of thought and emotion, as the work of the middle ages always was in spite of any rudeness of drawing or shortcoming in knowledge.
One drawback to the effectiveness of painted windows comes from the too common absence of any general plan for the glazing of the building. The donors of windows are allowed to insert whatever may please their individual tastes without regard to the rest of the glazing or the architectural requirements of the building; so that even where the window is good in itself, it fails in effect of decoration, and injures, or is injured, by its neighbours. The custodians of buildings before they allow any window to be put up should have some good plan of glazing schemed out embracing a system of subjects, an architectural arrangement, and a scheme of proportion of colour, and this plan should be carefully adhered to. Thus, one window would help the other, and even inferiority of design in one or two of the windows would be less noticed when the whole effect was pleasing. The gain of such a careful arrangement is sufficiently obvious in cases where the ancient glazing of a church is left intact; as, for instance, in the beautiful church of St Urbain at Troyes, a work of the end of the 13th century, and whose glazing is perhaps the most satisfactory example of glass-painting.
The worth of stained glass must mainly depend on the genuineness and spontaneity of the architecture it decorates: if that architecture is less than good, the stained-glass windows in it become a mere congeries of designs without unity of purpose, even though each one may be good in itself.
See works by Winston (1847 and 1865), Warrington (1848), F. Miller (1885), and especially Westlake, A History of Design in Painted Glass (4 vols. 1879-95).