Glazing

“ GLAZING.—The business of the glazier may be confined to the mere fitting and setting of glass (q.v.) , even the cutting up of the plates into squares being generally an independent art, requiring a degree of tact and judgment not necessarily possessed by the building artificer. The tools generally used by the glazier are the diamond for cutting, laths or straight edges, tee square, measuring rule, glazing knife, hacking knife and hammer, duster, sash tool, two-foot rule and a glazier’s cradle for carrying the glass. ”

“ Besides shaping and firing a vase, a potter must understand the art of glazing, to many the most alluring part of the craft; this comprises both the preparation of the glaze and its application to the pot. A glaze is a chemical compound, known as a silicate, which upon firing becomes a glassy substance. ”

“ To apply a glaze properly to the clay body is a great art, and upon it, as much as on the preparation of the glaze, final success depends. The glaze mixtures when applied are whitish or grayish; it is only after firing that they assume the wonderful range of colors which delight us so much today.
Fig. 50. Method of glazing: dipping
Fig. 51. Method of glazing: pouring
The Athenian potter had no ambition to produce brilliant color effects in glazing. ”

“ Indeed, the more delicate painting implies a certain avoidance of lead lines crossing it, and hence some very difficult feats of [Pg 63] glazing. This kind of inlaying was never very largely used, but on occasion not only a spot but even a ring of glass round it would be let in in this way. There is a window at Bourges in which the glories of the saints are inlaid with jewels of red, blue, green, and violet, which have more the effect of jewellery than if they had been glazed in the usual way. ”

“ Of late years each country has been learning so much from the others that the newest effort is very much in one direction. It seems to be agreed that the art of the window-maker begins with glazing, that the all-needful thing is beautiful glass, that painting may be reduced to a minimum, and on occasion (thanks to new developments in the making of glass) dispensed with altogether. A tendency has developed itself in the direction not merely of mosaic, but of carrying the glazier’s art farther than has been done before and rendering landscapes and even figure subjects in unpainted glass. ”

“ Glazing affords by itself scope for beautiful pattern work; but the old glaziers never carried their art as far as they might have done in the direction of ornament; their aim was always in the direction of picture; the idea was to make windows serve the purpose of coloured story books. That was beyond the art of the glazier. It was easy enough to represent the drapery of a saint by red glass, the ground on which he stood by green, the sky above by blue, his crown by yellow, the scroll in his hand by white, and his flesh by brownish pink ”

“ The first firing completed, the ware is said to be in the “biscuit,” and is then ready to be glazed. This matter of glazing is a very important one, and the success of the whole very largely depends upon the manner in which the operation is performed. To insure a successful result there must be the nicest adaptation of the materials composing the glaze to the body of the ware. The glaze for each kind of ware must be suited to its especial characteristics, and it can therefore be imagined that the number of glazes in use is very large. Each pottery has its own glaze and the variety is infinite. ”

“ The glaze was applied in several ways—by dipping in a tub of glazing liquid (i.e. glaze material finely levigated and mixed with water) , by painting the glaze on with a brush, or by blowing it on from a bamboo tube, the end of which was covered with a piece of tightly stretched gauze. One of the last operations was the finishing off of the foot, which was hollowed out and trimmed and the mark added (if it was to be in blue, as was usually the case) and covered with a spray of glaze. To the connoisseur the finish of the foot is full of meaning. ”

“ If, therefore, we want the qualities of deep, rich, luminous and translucent colour, which glass better than any other medium can give, we must resort to the use of pot-metal—that is to say, to glazing—assisted more or less by brown paint, used, not to get colour, but to stop it out, or to tone it down. ”

“ It is not only that the draughtsman has learnt to draw, and the painter to paint; they work on quite a different system. It was explained (page 44) how in early days the glazier conceived his design as mosaic, how he first thought it out in lead lines, and only relied on paint to help him out in details which glazing could not give him. Now, it is easy to see that the painter begins at the other end. He thinks out his picture as a painting, and relies upon glazing only for the colour which he cannot get without it. ”

“ Care should be taken not to fit the glass in iron bars tightly, but a good 1/8th in. play all round should be allowed. A few of the systems of patent roof glazing will be described in the following pages, together with illustrations.
The system of glazing known as the “British Challenge” (fig. 3) , with steel bars encased with a sheeting of 4-℔ lead, is very simple and durable, needs no painting, and can be fixed at as much as 8 ft. clear bearings, with the bars spaced 2 ft. ”

“ With the advent of the Perpendicular style the glazing became more uniform in character, the glass was thinner and lighter, the tints paler, and the whole effect more brilliant and transparent. The paintings for the most part consist of large figures under elaborate canopies, frequently occupying an entire light, and in the patterns and smaller decorations there is a greater freedom of design, and the whole treatment is more harmonious and artistic than in any other period. ”

“ And, when a number of lights go to make a window, it is the window, and no separate part of it, which is the main consideration.
By the end of the Gothic period, glass painters proceeded on an entirely different method from that of the 13th century. The designer of early days began with glazing: he thought in mosaic and leadwork; the lines he first drew were the lines of glazing; painting was only a supplementary process, enabling him to get what lead lines would not give. The Late Gothic draughtsman began with the idea of painting; glazing was to him of secondary importance ”

“ Mediæval glaziers did not attempt anything like foliated ornament in leaded glass, and for good reason. In such work the difficulty of doing without lines detrimental to the design is greatly increased, whereas abstract forms you can bend to your will, as you can bend your strip of lead. The more natural the forms employed the more nature has to be considered in rendering them, and nature declines to go always in the direction of simple glazing. ”

“ His first answers about glazing were most plain and unhesitating. Being asked if the Venetian painters did not use glazing, and that, in consequence, their pictures are liable to injury in cleaning, he says, “That is a question that can never be settled, because nobody can prove that they did use glazings.” Q. 116.—“Is it your opinion that they did, or that they did not?”—“I believe that the best painters of every school used very little, indeed, if any at all, of what is called glazing. I think it quite a modern quackery, that has nothing to do with the noble works of remote ages in art.” ”

“ A skillful grainer may also impart to the work the pleasant luster of natural wood. The same glazing method is applicable to colored paintings. If the glazing colors are prepared with wax, dissolved in French turpentine, one may likewise glaze with them on a size-paint ground. Glazing tube-oil colors thinned with turpentine and siccative, are also useful for this purpose. For the shadows, asphalt and Van Dyke brown are recommended, while the contour may be painted with size-paint. ”

“ Not only would the choir be too dark, but, besides, we would lose the contrast of light against gloom that renders it so impressive in its dignity. This observation introduces another type of glazing for which we shall seek in vain after this century. If we demand more light from our clerestory and at the same time insist on [Pg 30] coloured glass, then we must use fewer strips of light-obscuring lead, which means fewer and larger pieces of glass. Thus we will obtain more illumination than is yielded by the heavily-leaded windows below. ”

“ They know perfectly well that nobody above them knows as much as they, or, indeed, anything at all of their craft. Division of labour has made them "glaziers," as it has made the gentlemen above stairs, who do the cartoons or the painting, "artists." These last know nothing of glazing, why should glaziers know anything of art? It is perfectly just reasoning; they do their very best, and what they do is this. They take out the old, tender glass, with the colour hardly clinging to it, and they put it [Pg 320] into fresh leads, and then they solder up the joints. ”

“ The Keen-lung class of blue and red under the glaze was derived from that discovered in the Yung-ching period. Its application was developed with surprising skill by the finest workmen, so that the application of copper red under the glaze, in combination with blue, gave splendid opportunities for these artists to display their pre-eminent skill for freehand drawing in applying designs upon the biscuit porcelain before the glazing took place. If, for example, you pass your hand over a piece decorated under the glaze, you will find a surface perfectly smooth, the colour has sunk into the paste. ”

“ As yellow stain was not known at the time of glazing the first east window, it is absent from the early glass, although it is plentifully used in the heads, &c., of the additions made necessary in 1389 by the increased size of the window. One must not quarrel with the judicious restoration which has preserved so charming an ensemble. ”

“ Ouen (Rouen) and Evreux. This sudden revulsion did not appear in England where, indeed, there were no grounds for it, because, as we have just seen, the glaziers had already thoroughly grasped the need for, as well as the value of, light-admitting grisaille. That they thoroughly mastered the technique of uncoloured glass we will readily conclude from the splendid monuments to their genius in the “Five Sisters” at York, and the grisaille in the south transept at Salisbury, ideal glazing for a land of infrequent sunshine. ”

“ The glass was originally made for a church at Mechlin, Belgium, and though its figures have been necessarily readjusted to suit their new home, there remain so many sections of the vine as well as of the familiar name-labels as to make it obvious that the panels as originally combined made up a Tree of Jesse. The glazing as a whole is rich in tone, unmistakably Renaissance, and, best of all, so agreeably disposed in its present abiding-place as to make it seem as if it had always belonged there. ”

“ The use of coloured glass in the windows of buildings devoted to religious purposes appears to have been employed as early as the ninth century, but no examples remain of anything like so old a date, and we have only illuminated missals and primitive drawings by members of the conventual bodies to guide us in determining the earliest styles of coloured glazing. ”

“ GLAZING FINE-GRAIN POWDER. Glazing fine-grain.
The fine-grain powder thus dusted, is then glazed for three hours in barrels capable of holding 300lbs. which are 3ft. 6-in. in length, and 2ft. 8-in. in diameter, revolving at the rate of thirty two times in a minute. By the mere friction of the grains against each other and the inside of the barrel, a glaze is imparted, presenting a fine polished surface to the grain.
Object of glazing.
Powder glazed in this way withstands the action of moisture to a far greater extent than unglazed powder, and in transport very little dust is formed. ”

“ Scumbling is going over distance with white or grey, rubbing it hard and dry, so as to obscure the parts that stand too prominently out; it softens harshnesses, sends back portions, and does its part in aiding the general harmony of the distance and middle distance.
Glazing is the use of transparent colours with some sort of medium, such as madders, siennas, browns, to give richness to the depths, lower the tone in places needful, as foregrounds and such like, that come direct with all their local hues about them; it brings things forward, as scumbling sends objects back. ”

“ You find also in France rich colour-work surrounded by white glass—the work of a period when the powers that were became possessed of the idea that they must lighten the interior of their churches, and accordingly removed so much of the coloured glass as seemed good to their ignorance, and replaced it with plain glazing. ”

“ The glazing process was discovered by accident. A workman in a pottery in Germany, some time in the Middle Ages, to spite his employer, threw salt on some ware which was baking, but, to his amazement, found a beautiful glaze on the pottery instead of the ruin he had desired.
C. S. C., C.Y.
We would call the attention of the C. Y. P. R. U. this week to Mr. C. W. Fisher's sketch of "The First Grenadier of France," and to "Millie's Nile-Bird Hat," by Mr. Arthur Lindsley. Dr. ”

“ One should observe what an agreeable use is made of these small angels that people the traceries. The glazier has skilfully avoided the ugly effect which would have been produced had the white sheets of music or psalms been continued in a horizontal line around the chapel, and has so waved this white line up and down that it becomes as decorative as the labels so common in German glazing. This appearance of music on glass is rare in England and rarer still in France. ”