In leading we may use a bolder line for bounding and defining the main masses, and a thinner sort for subsidiary fittings; in this much will depend upon the scale of the work. The lead, which has a double groove, may be said to serve several functions. Its primary office is to hold the pieces of glass together: it forms the linework of the design, surrounding the figures and forms, separating them from each other and the background, as well as defining the secondary forms, as of drapery and other detail. Then, too, the lead joints ease the cutting of awkward shapes in the glass, which however should be avoided in planning the cartoon. Again, it may be used to obtain greater variety into large masses, as a piece of drapery, for instance.
THIRTEENTH CENTURY GLASS GRISAILLE, SALISBURY CATHEDRAL.
CARTOON FOR GLASS, SHOWING LEAD DESIGN, BY FORD MADOX BROWN.
CARTOON FOR GLASS, SHOWING LEAD DESIGN, BY FORD MADOX BROWN.
The cartoon being made, the next thing is to make the working drawing. This is done by laying a semi-transparent piece of paper over the cartoon, and tracing merely the lead lines and thus obtaining the skeleton of the window.
The glass is cut from this drawing, the cutter cutting the glass just within the lines, thus allowing for the heart of lead. The same drawing serves also for the leadworker to glaze the finished work upon.
The shapes of the whites and light colours are seen when the sheets are laid on the drawing; but the shapes of the dark colours, through which it is impossible to see the lead lines, must be obtained in another way.