In Saxon times this art found a home in England, the _artifices lapidearum et vitrearum fenestrarum_ having been invited to this country by Wilfrid, Bishop of York, in 709. The earliest specimen of ancient glass now in existence is in the choir-aisles of Canterbury Cathedral, where it was probably fixed when the cathedral was rebuilt after the fire in 1174. Coloured glass is of two kinds: (1) _Stained glass_, made by mixing metallic oxides with the glass when in a state of fusion, the colours thus going through the whole mass; (2) _Painted glass_, in which colouring is laid upon the white or tinted glass, and fixed by the action of fire. As the style of architecture changed, so the art of the glass-painter changed with it. In the Early English period the colours were very rich, and the designs consisted of medallions containing subjects taken from Holy Scripture, or the lives of the saints, upon grounds of ruby and blue. Mosaic patterns form the groundwork of the medallions, and a border of scrolls and foliage incloses the whole design. The outlines of the figures are formed by the lead. In the Decorated period the medallions disappear, and in their place we find single figures of large size under canopies. Instead of the mosaic backgrounds diaper-work in whole colours is used. Lights and shades are introduced in the dresses and canopies, and foliage is painted on the panes. The artists of this period first introduced heraldic devices into the windows. A border of white glass intervenes between the window and the medallion. When the Perpendicular style was in vogue the art of the glass-painter degenerated, as did that of the architect. Stained glass was little used, and the artists painted with enamel colours their designs upon the glass. The figures were larger than before, and the canopies of great size and with much architectural detail, landscapes and buildings appearing in the background. During this period inscriptions began to be used. In the sixteenth century the progress of the art was in the same direction. Large figures, and groups of figures, fill the whole window, and the existence of mullions is disregarded in the execution of the design. Glass-painting flourished until the Civil War period, and then died out.