The necessary element of strength in the construction of this huge window, which, at Gloucester was, as we have seen, obtained by building the whole window on the plan of a bow, is here provided by doubling the mullions below the second transom. An inner set has been constructed between three and four feet on the inside of those which sustain the glass, being connected with them by little flying arches and so acting as buttresses to them. This double set of mullions carries a gallery along its top at the level of the upper transom, while another runs across the base of the window, and from these it is possible to study the upper and lower tiers of lights at close quarters. Unfortunately access to these galleries is nowadays only granted as a great favour, but for those that can obtain it, it is well worth the trouble, for it is only from this position that the pages of this vast picture-book can be studied, and its story unravelled. Indeed I think the only adverse criticism that can be made of John Thornton's work is to question the artistic wisdom of putting so much beautiful work, on such a small scale,--for the delicate drawing and finish of the work is wonderful,--in a position in which it was invisible to the ordinary observer below. Perhaps John Thornton did not realize how small his panels would look,--panels three and a half feet square seem a fair size when you are working at them,--and no doubt access to the galleries was freer then than now; but a thirteenth century artist would not have made the mistake.[16] [Illustration: PLATE XLIV HEAD OF AN ARCHBISHOP, CANTERBURY Fifteenth Century] Yet the architectural effect of the whole is little, if at all, the worse for it. The smallness of the panels only increases one's sense of the size of the window and gives the glass a jewel-like quality. It is all a twinkle of beautiful colour. Neither have the repairs effected by the eighteenth century glaziers hurt it much--pieces of clear coloured glass put in to fill up holes, and on which the glazier has usually scratched his name and the date with his diamond. Rather, I think, these tiny touches of pure colour (for they used quite a good blue) add to it and give it a quality. What does detract from its beauty is the dirty quarry glazing which has been put outside it to protect it. Beautiful as the window still is, quite a third of its beauty of light and colour has been sacrificed by this means. [Sidenote: A transitional window.]