The process of enamel painting has been explained above (page 77). The one thing necessary to the safe performance of the operation is that the various gla.s.s pigments shall be of such consistency as to melt at a lower temperature than the gla.s.s on which they are painted. That, of course, must keep its shape in the kiln, or all would be spoilt. The melting of the pigment is, as a matter of fact, made easier by the admixture of some substance less unyielding than gla.s.s itself--such as borax--to make it flow. This "flux," as it is called, makes the gla.s.s with which it is mixed appreciably softer than the gla.s.s to which it is apparently quite safely fixed by the fire. It is thus more susceptible to the action of the atmosphere; it does not contract and expand equally with that; and in the course of time, perhaps no very long time, it scales off. Excepting in Swiss work (to which reference is made in Chapter IX.) this is so commonly so, that you may usually detect the use of enamel by the specks of white among the colour, where the pigment has worked itself free, altogether to the destruction of pictorial illusion.

And it is not only with transparent enamel that this happens, but also with the brown used by the later painters for shading.

The brown tracing and painting colour was originally a hard metallic colour which required intense heat to make it flow. The gla.s.s had to be made almost red-hot, at which great heat there was always a possibility that the pigment might be fired away altogether, and the painter's labour lost. In the case of the thirteenth century painter's work the danger was not very serious. Thanks to the downright and sometimes even brutal way in which he was accustomed to lay on the paint, solidly and without subtlety of shade, his work was pretty well able to take care of itself in the kiln. It was the more delicate painting which was most in danger of being burnt away; and in proportion as men learnt to carry their painting further, and to get delicate modelling, they became increasingly anxious to avoid all possibility of any such catastrophe.

The easiest way of doing this was (as in the case of transparent enamel) to soften this colour with flux. That enabled them to fire their gla.s.s at a much lower heat, at which there was no risk of losing the painting, and they were able so to make sure of getting the soft gradations of shade they wanted; and the more the painter strove to get pictorial effects the more he was tempted to soften his pigment; but, according as the flux made the colour easier to manage in the fire, it made it less to be depended upon afterwards; and the later the work, and the more pictorial its character, the more surely the painting proves at this date to have lost its hold upon the gla.s.s. In many a seventeenth century window the Donors were depicted in their Sunday suits of black velvet and fur, the texture quite wonderfully given; now their garments are very much the worse for wear, more than threadbare. The black or brown is rich no longer, it is pitted with specks of raw white light; sometimes the colour has peeled off _en ma.s.se_. Time has dealt comparatively kindly with the gentlemen on page 81, but in the gla.s.s there is an air of decay about their sable cloaks which takes considerably away from their dignity. It is one characteristic of enamelled windows that they do not mellow with age, like mosaic gla.s.s, but only get shabby.

Any one altogether unacquainted with the characteristics of style is apt to be very much at fault as to the date of a window. The later windows are in so much more dilapidated a condition than the earlier that they are quite commonly mistaken for the older.

It has to be borne in mind that most of the devices adopted by the gla.s.s painters--the use, namely, of large sheets of fragile gla.s.s, and the avoidance of strengthening leads, no less than the resort to soft enamel, whether for colour or for shading--all go to make it more perishable.

It may be said that the decay of the later painting is due not so much to the use of enamel as to the employment of soft flux. That is true.

But when it comes to the painting of texture and the like, the temptation to use soft colour has generally proved to be irresistible.

One is forced to the conclusion that the aim of the later gla.s.s painter was entirely wrong; that for the sake of pictorial advantages--which went for very little in a scheme of effective church decoration, even if they did not always detract from the breadth of the work--he gave up the qualities which go at once to make gla.s.s glorious, and to give it permanence. Whatever the merits of seventeenth century gla.s.s painting they are not the merits of gla.s.s; there is little about it that counts for gla.s.s, little that is suggestive of gla.s.s--except the breakages it has suffered.

What is said of seventeenth century gla.s.s applies also to that of the eighteenth century, only with more force. Sir Joshua and Benjamin West were quite helpless to raise the art out of the slough into which it had fallen, for they were themselves ignorant of its technique, and did not know what could be done in gla.s.s. It was not until the Gothic revival in our own century, and a return to mosaic principles, that stained gla.s.s awoke to new life.

CHAPTER IX.

THE NEEDLE POINT IN GLa.s.s PAINTING.

Allusion has been made to the gla.s.s painter's use of the point for sc.r.a.ping out lights, and especially diapers upon gla.s.s coated with pigment. These are often quite lace-like in their delicacy. That would be a poor compliment if it meant that the gla.s.s painter had had no more wit than to imitate the effects produced in a material absolutely unlike gla.s.s. But it is not merely for want of a better word that the term lace-like is used. It is strictly appropriate, and for a very good reason. It was explained how from the first the gla.s.s painter would use the stick end of his brush to sc.r.a.pe out sharp lights in his painting, or even diaper patterns out of a tint. The latest gla.s.s painters made more and more use of the point, and of a finer point than the brush end, until, in Swiss work, they adopted the pen and the needle itself. It is not surprising, then, that point-work should resemble point-work, though the one be in thread and the other on gla.s.s. The strange thing would have been if it were not so. Thus it comes about that much of the Swiss diaper work is most aptly described as lace-like in effect.

The field of a small shield is frequently diapered with a pattern so fine that it could only have been produced with a fine point. Some of the diapers opposite may be identified as portions of heraldic shields.

On a shield it may be taken to represent the engraving of the metal surface of the thing itself; and, indeed, here again is a significant resemblance between two technical processes.

To scratch with a needle or with a graver is much the same thing; and thus many a Swiss diaper suggests damascening, and might just as well have been executed in bright lines of gold or silver filigree, beaten into lines graven in steel or iron, as sc.r.a.ped out of a tint on gla.s.s.

[Ill.u.s.tration: 49. EXAMPLES OF SCRATCHING OUT.]

But the use of the point was by no means reserved for ornamental detail.

It became the main resource of the painter, and so much so, that this technique, or this development of technique, is the most striking characteristic of Swiss gla.s.s painting--if that should be called painting which has really more affinity with etching.

For the laying on of the paint in the form of solid colour, or of matted tint, or of skilfully floated wash, is only the groundwork of the Swiss gla.s.s painter's method. It scarcely needs to be explained how admirably the point adapted itself to the representation of hair, fur, feathers, and the like. The familiar bears, for example, the device of the city of Berne, which occur very frequently in Swiss heraldic work, are rendered at Lucerne in the most marvellously skilful manner. First a juicy wash of colour is floated all over the body of the beast, more or less translucent, but judiciously varied so as to give _a peu pres_ the modelling of the creature. Then with a fine point the lines of the fur are sc.r.a.ped out, always with an eye to the further development of the modelling. Finally, the sharp lights are softened, where necessary, with delicate tint, and a few fine hair-lines are put in with a brush in dark brown.

By no conceivable method of execution could certain textures be better rendered than this. A similar process is adopted in rendering the damascened surface of slightly rounded shields; but in that case the modelling of the ground is first obtained by means of matt, not wash.

Black as a local colour, whether by way of heraldic tincture or to represent velvet in costume, was very generally used; but in such small quant.i.ties always as entirely to justify its use. The practice, that is to say, referred to on page 57, with reference to the German work at Shrewsbury, was carried further. This was quite a different thing from what occurs, for example, in a late window at Montmorency, where four brown Benedictine monks are frocked in muddy paint: that is a fault of judgment no skill in execution could make good. In the case of black used by way of local colour the drawing lines were of course sc.r.a.ped out in clear gla.s.s, and toned, if need were, with tint. The hair, cap, and feathers of the figure opposite ill.u.s.trate the processes of execution above described; the chain armour about the man's neck is also very deftly suggested.

[Ill.u.s.tration: 50. NEEDLE POINT WORK, SWISS.]

The use of the point went further than rendering the texture of hair, and so on. It was used for the rendering of all texture and the completion of modelling everywhere. The Swiss gla.s.s painter did very much what is done in large when one draws on brown or grey paper in white and black; only instead of black chalk he used brown paint, and instead of putting on white chalk he sc.r.a.ped away a half tint with which he had begun by coating the gla.s.s; and of course he worked in small.

One knows by experience how much more telling the white crayon is than the black, how much more modelling you seem to get with very little drawing; and so it is in gla.s.s; and so it was that the gla.s.s painter depended so much more upon taking out lights than upon putting in darks.

The difference between the Swiss manner and the process already described in reference to Renaissance church gla.s.s was mainly that, working upon so much smaller a scale, the artist depended so much more upon the point. His work is, in fact, a kind of etching. It is the exact reverse of drawing in pen and ink, where the draughtsman works line by line up to his darkest shadow. Here he works line by line to clearest light, precisely as the etcher draws his negative upon copper, only on gla.s.s it is the positive picture which is produced. So far as manipulation is concerned the two processes are identical. It is indeed quite within the bounds of possibility that the method of the gla.s.s painter (and not that of the damascener, as generally supposed) may first have put the etcher upon the track of his technique.

The method of workmanship employed by the painter is shown pretty clearly on page 90. In spite of a certain granular surface given by the stone employed by the lithographer in reproducing the design, it is quite clearly seen how the man's armour and the texture of the silk in his sleeves is all obtained by the point. The trace of the needle is not clearly shown in the flesh, except in the hand upon his hip; but on page 93 it is everywhere apparent--in the shading of the architecture, at the top of the page, in the damascening of the tops of shields below, in the drawing of the pastoral staff, in the modelling of the mitre and the representation of the jewels upon it, no less than in the rendering of the texture of the silk.

This ultra-delicacy of workmanship was naturally carried to its furthest extent upon white gla.s.s or upon white and stain, but the same method was employed with pot-metal colour; and, during the early part of the sixteenth century at least, pot-metal colour was used when it conveniently could be, and the leading was sometimes cleverly schemed, though the gla.s.s employed was often crude in colour. Eventually, in Switzerland as everywhere, enamel colour succeeded pot-metal, by which, of course, it would have been impossible correctly to render the tinctures of elaborately quartered shields on the minute scale to which they were customarily drawn. At Lucerne, for example, there are some small circular medallions with coats of arms not much bigger than occur on the back of an old-fashioned watchcase. Needless to say that there the drawing is done entirely with a point. This kind of thing is, of course, gla.s.s painting in miniature; it is not meant to say that it is effective; but it is none the less marvellously done. It was at its best, roughly speaking, from 1530 to a little later than 1600. Some of the very best that was ever done, now at the Rath-haus at Lucerne, bears date from 1606-1609; there is some also at the Hof-kirche there; but that is out of the reach of ordinary sight, and this is placed where it can conveniently be studied. The point-work, it should be understood, is still always sc.r.a.ped out of brown, or it may be black. The enamel that may be used with it is floated on independently of this; and as time went on enamel was of course very largely used, especially in the seventeenth century. To the credit of the Swiss it should be said that, alone among later gla.s.s painters, they were at once conscientious and expert in the chemistry of their art, and used enamel which has been proof against time. They knew their trade, and practised it devotedly.

Possibly it was the small scale upon which they worked which enabled them to fuse the enamel thoroughly with the gla.s.s. It is due to them also to say that, though their style may have been finikin, there was nothing feeble about their workmanship; that was masterly. And they remain the masters of delicate manipulation and finish in gla.s.s painting.

Although the needle point was used to most effective purpose in Swiss gla.s.s it did not of course entirely supersede other methods. At the Germanic Museum at Nuremberg (where there is a fair amount of good work, 1502-1672) there is some matted tint which is shaded and then lined in brown, much after the manner of one of Durer's woodcuts. It has very much the appearance of a pen drawing shaded, as many of the old masters'

drawings were, in brown wash.

[Ill.u.s.tration: 51. NEEDLE-POINT WORK, SWISS.]

A fair amount of simple figure work in white and stain continued to be done, in which outline went for a good deal, and matted shadow was only here and there helped out with the point. In landscape backgrounds shade tint was sometimes broadly and directly floated on. But as often as not shading was executed to a great extent with the needle, whilst local colour was painted with enamel. Even in a.s.sociation with admirable heraldry and figure work, one finds distant figure groups and landscapes painted in this way. They look more like coloured magic-lantern slides than painted window gla.s.s.

Sometimes subtlety of workmanship was carried rather beyond the bounds of discretion, as when at Nuremberg (1530) faces were painted in tint against clear gla.s.s, without outline, the mere shading, delicate as it is, being depended upon to relieve them from the ground. It must be confessed that, near to the eye, it does that; but the practice does not recommend itself.

It is remarkable how very faint a matt of colour on the surface of transparent gla.s.s gives a sort of opacity to it which distinguishes it from the clear ground. Sometimes white enamel is used, sometimes perhaps a mere coat of flux: it is difficult to say what it is, but there is often on the lightest portions of the painted gla.s.s no more than the veriest film, to show that it has been painted.

It is obvious that gla.s.s of the most delicate character described must be the work of the designer; and it seems clear, from numerous drawings extant, which are evidently the cartoons for Swiss window panes, that the draughtsman contemplated carrying out his design himself. At all events, he frequently left so much out of these drawings, that, if he trusted to the painting of another, no little of the credit of the draughtsmanship was due to that other, and he was at least part designer of the window. In gla.s.s where painting is carried to a high state of perfection it goes without saying that the painter must be an artist second only to the designer. Invention and technical power do not always go together. But if the designer can paint his own gla.s.s, and will, so much the better. It is more than probable that the best gla.s.s is the autograph work of the designer.

CHAPTER X.

THE RESOURCES OF THE GLa.s.s PAINTER--A RECAPITULATION.

Having followed the course of technique thus far, it may be as well to survey the situation and see where we now stand. Suppose an artist altogether without experience in gla.s.s had occasion to design a window.

The first thing he would want to know would be the means at his command at this present moment, and what dependence he could place upon them.

That is what it is intended briefly to set forth in this chapter, quite without reference to date or style or anything but the capacities of the material. The question is, what can be done with it? Not until a man knows that is he in a position to make up his mind as to what he will do.

If he ask, as artists will, why cannot he do just what he likes, and as he likes, the answer is: because gla.s.s was not made for him, and will only do what he wants on condition of his demands upon it being reasonable. He might find it pleasanter if the world revolved round him; but it does not. If he would make a window he must go the way of gla.s.s; and the way of gla.s.s is this:--

In the first place, it is mosaic. It may be a mosaic of white gla.s.s or of the pearly tints which go to make what is termed grisaille, in which case the leads which bind the gla.s.s together form the pattern, or, at all events, a feature in it. Or it may be of coloured gla.s.s, or of white and colour, in which case the gla.s.s forms the pattern, and the lead joints are more or less lost in the outline of the design.

If the pattern is in white upon a deep-coloured ground the lead joints crossing the pattern and not forming part of it are, as it were, eaten up by the spreading rays of white light, and, supposing them to be judiciously contrived, do not count for much. On the other hand, the lead joints crossing the coloured ground are lost in its depth.

Advantage is taken of this to break up the ground more than would be necessary for convenience of glazing, or of strength when glazed, and so to get that variety of pot-metal upon which so much of the beauty of gla.s.s colour depends.

[Ill.u.s.tration: 52. PLAIN GLAZING, EARLY FRENCH.]

To give satisfactory colour the best of pot-metal gla.s.s is essential.

Structural conditions which a man is bound to take into account in his design are--that the shapes he draws must be such as can readily be cut by the glazier; that his lead joints must be so schemed as, where not lost in the gla.s.s, to form part of the design, strengthening, for example, the outlines; that his plan must at intervals include provision for substantial iron bars which shall not interfere with the drawing.

He must understand that each separate colour in his composition is represented by a separate piece of gla.s.s, cut out of a sheet of the required colour. There may, and should, however, be variety in it. A sheet of gla.s.s varies in depth of tone according to its thickness, which in the best gla.s.s is never even; moreover, it may be streaked or otherwise accidentally varied; and so considerable play of tint may be got in a well-selected piece of pot-metal. Should a tint be required which the palette of the glazier does not supply it may sometimes be obtained by leading up two thicknesses of gla.s.s together. This expedient is called "plating."

[Ill.u.s.tration: 53. MOSAIC GLa.s.s, a.s.sISI.]

There are two very workmanlike ways in which white and colour may be obtained in one piece of gla.s.s. If the gla.s.s is not coloured throughout its thickness, but only a part of the way through, the coloured part may be eaten away in places by acid (it used formerly to be tediously abraded); and so a pattern of white may be traced upon a ground of blue, for example, or, as is more common, ruby.

A piece of white or pale coloured gla.s.s may further be _stained_, but only, so far, of one colour, yellow. The window opposite is all in white and golden-yellow. This result is produced by the action of silver upon it, which, at a sufficient temperature, develops a tint varying from lemon to orange of beautiful quality, and as imperishable as the gla.s.s; but one cannot be quite certain always as to the precise shade it will take in the fire. On blue it gives green, and so on.