The Craft of Stained Glass
by Charles Paine
Stained glass is more usually associated with ecclesiastical architecture than with domestic architecture.
The field of domestic architecture has yet to be explored.
In this enlightened age the control of warm and cold light in our homes is worthy of more thought and consideration.
Much thought has been given to artificial lighting, but little to the control of day lighting. A hot light can be made cool, a cold light warm and inviting, gloom dispelled and brilliancy made restful.
An elementary understanding of the possibilities and limitations of the craft may help to an appreciation of its qualities.
A stained glass window is composed of pieces of plain and coloured glass held together by strips of lead; the distinctive and especial attributes of stained glass are peculiar to the craft and should not be confused with paintings.
The light shines through and not on the window. Glass is made by being blown into a bubble, which is then opened at the ends, and while hot, manipulated into a cylinder; it is then cut down one side and opened out upon a flattening stone into a sheet. It is this stone which gives the glass its texture. There are two kinds of glass, Potmetal: glass where the colour goes all through; as in the case of a rare jewel, and flashed glass.
In the latter, a bubble is blown, mainly composed of white glass; but before blowing, it is dipped into glass of another colour and both are blown together and fused as one.
The effect of brilliance is largely due to the use of glass that varies in thickness, and to imagine the effect of light from sun-up to sun-down shining through glass such as I have ventured to describe at once dispels the gloom usually associated with the craft.
In painting, coloured pigments are not used, but the features of a face, the folds of drapery, all forms, in short, are traced in a monochrome (chiefly oxide of iron) on the various coloured glasses. Yellow stain is the only thing in the nature of a coloured pigment permissible, and this is used with discretion on the back of the glass before firing in the kiln.
It can be seen, therefore, that a thorough knowledge of the possibilities and limitations of the materials is essential to the designer of stained glass.
The possibilities of invention are inexhaustible; roughly, the procedure is as follows:
A sketch is made to scale, and from this a full-sized working drawing is developed on the lines of the leading, which are not an afterthought around a drawing but, on the contrary, are the structure of the design.
There must be no doubt as to the intention of the artist in this working drawing, for from this drawing a tracing is made of the lead lines only, and from this tracing patterns are made for every piece of glass in the window.
The artist then selects the glass that will not only express his ideas but control the particular lighting required. The glass is now cut to the various patterns with the wheel or diamond. Each piece of glass that needs painting is placed over the working drawing and the form traced through. By gradual stages the painting is developed on a glass easel up to the strength of the working drawing.
It is not unusual (owing to the different natures of the glass) to work over the window two or three times until one arrives at the required strength, otherwise the whole or parts of the scheme would fade away in the kiln. The artist, of course, translates his drawing onto the glass and does not leave it to other hands to carry out.
Apparently, we have now to fit together a glorious jigsaw puzzle. (It is surprising how soon one comes to know the different members of this large and joyous family.)
In between each piece of glass the lead must be constructively guided. The joints are then soldered back and front and the window is cemented, likewise back and front. Certain effects are produced by placing one glass behind another in the same lead; such pieces must be sealed with putty before cementing, otherwise the cement would mark in between the glasses.
Time will mellow and further enrich the permanent qualities of the materials used in a stained glass window, but they must accumulate age only with the passing years.
A copy of the original article with illustrations was posted under ‘Stained Glass’ October 20, 2017